Side sleeping is the most common sleeping position for adults. Research shows that around 54% of us roll onto our sides when we want to get some kip, whether that's in a comfy bed at home or inside a toasty sleeping bag in the wilderness.

With so many people sleeping on their sides, it's a surprise that there aren't more sleeping bags like this one. The Big Agnes Sidewinder Camp 35 features a cocoon-style fit that hugs the contours of your body when you roll onto your side, and it's now available for just $100.73 in men's sizes and $118.73 in women's sizes at REI.

The side-sleeping design aims to increase comfort and keep insulation close to your body to stop irritating air pockets. Everything down to the thermally efficient footbox mimics the shape you make lying on your side.

Along with its unique design, the Sidewinder Camp 35 was built to be a reliable and insulating model that can keep you warm in temperatures down to 35°F (-2°C). It's made from dependable ripstop nylon and features a PFC-free water repellent finish to protect against the elements. It's filled with toasty FireLine Eco 100% post-consumer recycled polyester and stops heat from escaping with a no-draft anti-snag locking zipper.

If you're after something a little warmer, the Sidewinder Camp 20 model is rated down to 20°F (-7°C), and is also available in men's and women's sizes at REI.

Don't worry if you're not in the US, you can look below for today's best Big Agnes sleeping bag deals where you are.

• The best sleeping bags: camp in comfort
• The best camping pillows: tested for comfort in the backcountry

After months of anticipation, Amazon Prime Day is here and in full swing, offering great deals on all sorts of outdoor gear on Amazon. There are plenty of bargains to choose from, including big reductions on well-rated Garmin sports watches, trail running shoes, and more, but funnily enough, many of the best camping deals aren't on Amazon at all.

Several big-name outdoor retailers have also cut their prices in a bid to keep up with Amazon's Prime Day madness. As a result, there are loads of great outdoor deals to choose from at other retailers like REI, Backcountry and Dick's Sporting Goods.

To save you time and money, we've scrolled through all the major sales to find the top five camping deals currently available.

Among our picks, you'll find insulating sleeping bags like the Kelty Cosmic 20 and Patagonia Fitz Roy Down, which are both over $100 off. There are also great backpacking tent deals to take advantage of, including the waterproof Tadpole SL tent from The North Face, which can be stuffed into a small portable bag and is now available for just $300 at Dick's Sporting Goods.

Read on for our full list and a roundup of today's best tent, sleeping bag, and camping stove deals from across the web.

Our favorite camping deals

More epic deals

Stick with Advnture for handpicked deals from the Amazon Prime Day sale, which runs until July 11.

• The best camping tents: for superb backcountry adventures
• The best sleeping bags: for comfort in camp

When I trekked to Everest Base Camp, I was warned that temperatures plummet at night and the teahouses where we'd be sleeping aren't heated, so I armed myself with an awesome sleeping bag that wasn't just warm but let me sleep in different positions since I'd be spending 11 nights in it.

I took the Big Agnes Torchlight EXP 0 Sleeping Bag, which you can grab for just $337.46 right now in Backcountry's summer sale if you're in the market for a really good bag.

Designed and tested in the mountains of Colorado, this Big Agnes bag has a comfort rating of 0F (-18C) and is made with hydrophobic down, so it continues to keep you cozy in damp conditions.

But the most exciting part is that it features Big Agnes' patent-pending design that includes an extra zip so it can be expanded for side sleepers, and that made the difference between a good night's sleep and a night of tossing and turning for me, even when we reached almost 17,000ft.

This deal applies to the brilliant Tangelo/Chinois Green colorway in all sizes and the sale ends on July 6, unless sizes run out first, so I recommend you don't delay.

Not in the US? Read on to find the best deals on the Big Agnes Torchlight EXP 0 Sleeping Bag near you.

This isn't the lightest or most packable bag I own, but with a compression sack you can bring it along on backpacking trips and it's great for car camping. It's fully insulated top and bottom using baffled construction and a comfortable jacket-style hood opening contours to the shape of your face for a snug fit, plus it has straps to attach it to your sleeping pad so you don't roll off in the night.

If you're not in the US, here are today's best deals on the Big Agnes Torchlight EXP 0 Sleeping Bag where you are.

• The best sleeping bags: for comfort in camp
• The best sleeping pads: comfy mats for all camping trips
• The best camping pillows: tested for comfort in the backcountry

Changing robes are big news. Where once they were simple pull-over hoodies fashioned by surfers who stitched together a couple of old towels to protect their dignity on the beach, the market has exploded in recent years and is now awash (no pun intended) with highly technical garments, with prices to match.

It's pretty standard now to see changing robes sported by dog walkers, parents on the school run, and around many a campfire. Of course, wild swimmers and paddleboarders are still wearing them too.

But if you want the coverage of a changing robe without the voluminous size then other options are appearing.

Voited is the latest company to capitalise on this growing niche, and has just launched the Wearever jacket - a 3-in-1 garment designed for backcountry adventures and campfire cookouts.

The Wearever jacket is a twist on Voited's Drycoat 2.0 and offers the same protection in a slimmed down fit.

In a statement announcing its release the company said: "After many customers shared stories around why they use their drycoats for dog walks, school runs and countryside hikes etc, this jacket was constructed to offer the same comfort as a drycoat but with considered design tweaks to make it more versatile day-to-day."

The hooded outer has a hydrostatic head of 18,000mm and a breathability rating of 5,000mm, with a full length zip that has a zip garage and storm flap to keep the elements out.

It's made from 50D 100% Repreve Our Ocean® recycled polyester, which is manufactured from discarded plastic bottles, aimed at reducing ocean pollution. It's also treated with Bionic Finish®Eco Fluorine Free DWR (durable water repellent) and uses what the company calls TRFF technology in its insulation to created a three-dimensional grid structure for exceptional warmth, compression, and rebound properties.

The jacket also has fleece-lined and zippered side pockets with storm flaps, to prevent water seeping in during a downpour.

The padded inner vest, which attaches into the jacket with loops and poppers, is full length and, like the jacket, closes with a zip.

CloudTouch fleece lines the vest and pockets and hood of the outer to provide extra coziness. The vest is also reversible, and you can see what that looks like in the image below.

The Voited Wearever jacket is available online now in the UK, comes in sizes XS to XL and costs £199.

We've got one on test at Advnture, so look out for a full review soon.

• The best changing robes: cocoon yourself post-swim in a protective layer
• The best waterproof jackets 2025: brave the elements with these top-rated hard and softshells

Forclaz Trekking Sleeping Bag MT900 5°C Down: first impressions

Decathlon has been behind some of the best bang-for-your-buck outdoor gear in recent years. Its line of hyper-considered and extensively tested trekking tents all offer exceptional value for money, and I’ve been nothing but impressed by everything I’ve tried. But does that apply to sleeping bags? Earlier this year, I visited Decathlon at its production facility in the French Alps to find out about how they design, test and validate products. And came away with a shiny new MT900 5°C sleeping bag from their trekking brand Forclaz to test.

Costing £149.99 when bought directly from Decathlon in the UK, the Forclaz MT900 5°C sleeping bag is a down-filled, 3-season sleeping bag that sits at the intersection between big-brand-feel and price. Unlike its line of backpacking tents, however – such as the Forclaz MT900 Trekking Tarp Tent which comes in at less than half the price of most big-brand competitors – Decathlon’s 3-season sleeping bag is only a little cheaper than big-brand alternatives. So, how does it perform in comparison?

Forclaz Trekking Sleeping Bag MT900 5°C Down: in the wild

I’ve had my hands on a Forclaz MT900 5°C sleeping bag for all three seasons now. That means I’ve been able to put it up against the full gambit of conditions it was built for, ranging from temperatures hovering around its 5°C / 41°F limit all the way up to balmy summer nights where the mercury remained well above 16°C / 61°F. I’ve used it in dry conditions, windy conditions and outright monsoon-style conditions during a snap summer storm in Dartmoor National Park in England. So it’s safe to say that I’ve given it a fair crack of the whip.

The first thing I appreciate about this bag is its size and weight. Coming in at just 830g / 1.8lbs, it weighs less than a liter of water and packs down to about the same size as a rugby ball. That means it lends itself well to ultralight trips and adventures where pack space is a premium, such as bikepacking, fastpacking or UL backpacking trips. In fact, the only bag I own that is lighter than the Forclaz is the Sea to Summit Spark 7°C which just happens to be half the weight. That being said, it also happens to cost twice the price and is considerably less warm, so I found that I’ve continued to use the Forclaz MT900 5°C sleeping bag on UL trips throughout 2024, despite having a much more ‘premium’ bag on my shelf.

Inside the large version of the bag, Decathlon has stuffed 370g / 13oz of 700 fill-power, RDS-certified and traceable insulation. This comprises 90% gray duck down and 10% gray duck feathers. This is wrapped together inside a cozy polyamide shell with vertical baffles that feels great against your skin, reduces cold spots and ensures an even spread of down throughout the bag.

Another thing worth noting about the Forclaz MT900 5°C sleeping bag is the quality of the zipper. In all my many nights, it barely snagged and was easy to loosen whenever it did. This never cut into the material or caused any damage whatsoever, which can often be a problem with lightweight sleeping bags like the Forclaz MT900 5°C. What’s more, featuring a soft polyamide internal baffle, the zipper is also fully protected against drafts and comes with a handy internal stuff pocket for keeping things like your phone safe and warm through the night.

Finally, it’s worth mentioning the stuff sack, which is easily the best of its kind I’ve come across. The sack provided with the Forclaz MT900 5°C is a dry bag that comes with two clips for extra compression. This means that you can safely carry your down bag through the worst conditions out of the box, and you don’t need to buy an additional dry bag for use in damp conditions (as is so often the case, even with premium lines).

Forclaz Trekking Sleeping Bag MT900 5°C Down: warmth

I’d say that the Forclaz MT900 5°C sleeping bag is mostly good down to 5°C / 41°F. When combined with a warm pad, such as the Thermarest Neoair Xlite NXT, I didn’t have any issues down to 7°C / 45°F, so I’d happily take it down a little further than that when combined with some base layers and maybe a thin jacket. But I do run cold! As ever, however, I find it incredibly difficult speaking about the warmth of a bag, as what’s warm for me might not be warm for you. In a welcome move, however, it’s nice to see that Decathlon has listed the comfort temperature as a part of this bag’s name and not the limit temperature, as is so often the case with sleeping bags. So top marks to Decathlon there.

One last thing of note is the cut of the bag. Unlike your usual mummy-style sleeping bag, the Forclaz MT900 5°C comes with an anatomical hood that is tight over your head. Unlike regular mummy bags, which gently taper from the widest point around the shoulders up a narrow rounded tip above the head, this bag is cut like a down jacket, meaning it’s cut inwards sharply around the shoulders and more naturally shaped around your head. I found this to do a great job at keeping in the warmth, though the more restrictive cut of the bag did take some getting used to. Over its use, however, I grew to love it, and it meant that I actually made use of the hood of the bag for a change, rather than just resting my head inside an open cavern, as is often the case with regular mummy bags. Additionally, due to the tighter cut around the shoulders, I also found that the bag moved more with me as I rolled around at night, which was a welcome revelation as a wriggler.

Overall, I really like the Forclaz MT900 5°C and find it to be an excellent option for a great price. Granted, at £150, it’s pricey for Decathlon, but I think you’ll have to spend considerably more to find a comparable 3-season down bag from any of the big-name brands out there.

• How Advnture tests products

Sea to Summit Ascent: first impressions

I’ve been a fan of the Australian brand Sea to Summit for quite some time now. Each time I’ve tried some of their gear over the years, it’s always felt unique, adding their own spin to tried and tested designs to create camping gear that many love (and a few people loathe!).

Take their epic Ether Light XT Extreme sleeping pad, for example. This stands out as one of the best four-season pads in my eyes, being luxuriously comfortable yet lightweight and packable for real four-season adventuring. Their incredible Ember range of lightweight quilts also took me by surprise, as the brand managed to turn something as plain and simple as a quilt into a versatile bit of backpacking gear that does way more than just cover you up in the night. But how revolutionary can you make a sleeping bag?

Enter the Sea to Summit Ascent, the brand’s attempt to add layers of versatility to your sleep system. Comprising 100% Ultra-Dry Down 750+ Loft goose down, the bag comes with some of the highest quality compressible insulation on the market, packs down small and weighs a super-lightweight 1,020g. Promising to keep you warm in temperatures below freezing, these stats are already impressive enough, but it’s the bag’s extra features – namely a series of additional zips – that really make it stand out in the market.

So when I was given the chance to test one earlier this year, I couldn’t wait to see whether Sea to Summit really have improved on a design that has long felt unimprovable.

Sea to Summit Ascent: in the wild

I’ve had my hands on the Sea to Summit Ascent sleeping bag since the start of 2024 and have been able to put it up against the full gamut of British weather in that time. I’ve used it out on Dartmoor in temperatures below freezing, in Bannau Brycheiniog (the Brecon Beacons) in balmy summer conditions we don’t get treated to all that often, and on several short overnighters paired with a lightweight running setup. I’ve used it in the wind, rain and sun – with the only condition I’ve not tested it in (yet!) being snow. Although I’d argue that’s not really what this bag was built for anyway, at least out of the box (more on that later).

The first thing I really like about the Ascent is the quality of the insulation. To call this lofty is an understatement: no matter how long it sits in the loft bag, it always pops to life immediately. The result is a super cozy, plush sleeping bag that adds a little bit of luxury to your outdoor escapades. With a thin nylon inner shell, the material is also very soft on your skin and doesn’t result in any clamminess, as is often the case with ultralight sleeping bags.

For me, however, the standout part of this whole bag has to be the zips. Seriously, when I first played around with this, I wondered if Sea to Summit had ordered too many and needed to use them up, as there are more zips on this sleeping bag than any other I’ve tried. But to my surprise, this seemingly excessive amount of zips proved to be a great addition: they add an additional layer of versatility to a 3.5-season bag and make it super comfortable in a huge range of conditions.

You see, the three-season moniker has long been a gripe of mine, as bags that are suitable for three-season conditions are normally too warm for high summer and too cold for deep winter. This makes them more of a shoulder-season bag suitable for two seasons, not three.

But thanks to the volume of zips on the Ascent you can open up both sides of the bag and the foot box. This allows you to poke a foot out when you're warm or batten down the hatches tight when you’re cold. You can wear it like a jacket with both your arms hanging out, and you can even zip it to an adjoining bag to make a luxury sleeping space for two. This makes this Ascent sleeping bag the first true 3-season+ bag I’ve ever come across, as it’s suitable for both very cold and very warm conditions.

Sea to Summit Ascent: extra features

As well as extra zips, the Ascent also comes with a bunch of additional features that I really enjoy. Firstly, there’s the storage sack: this is more of a cube than a saggy net bag, which makes this bag easier to store on your gear shelf. Granted, this is a minor consideration for people who don’t have a whole shelf of sleeping bags but, for me, I appreciate the thought that’s gone into this part of the user experience.

My favorite extra feature, though, is easily the ability to pair this bag with a quilt. In a move that turns the first true three-season+ bag I’ve ever come across into the first true four-season+ modular sleep system I’ve ever come across, the Ascent features some simple hooks on the side and the foot box to secure a quilt. Known as Sea to Summit’s ‘QuiltLock System’, it lets you reliably mount a compatible quilt (such as the Sea to Summit Ember or many third-party brands) to boost the thermal performance of the bag, giving you a system that you can use in practically any conditions.

This is excellent, and it means that you no longer need a summer bag, a shoulder-season bag and a deep winter bag. Instead, all you need is a Sea to Summit Ascent for anything above freezing and an additional lightweight quilt for anything below around 25°F (-4°C), and you’re set!

To protect that lofty down, the Spark II comes wrapped in a 10D nylon shell. Despite being super soft and comfortable on your skin, I also found that this does a decent job of keeping water out as long as you shake it off quickly and don’t give it a chance to soak in.

The Sea to Summit Ascent: warmth

Which leads us on to warmth. In my experience, this is always the hardest (and most meaningless) aspect of a sleeping bag to critique, as my comfort levels will always differ from yours.

In any case, this Sea to Summit Ascent comes with a limit temperature of 15°F (-9°C), which means you’ll be uncomfortably cold in any temperatures below that (in laboratory conditions). For fairness and transparency, however, you should view this as nothing more than fancy marketing. The comfort temperature is all you should pay attention to, which I’d put at about freezing (or slightly below).

When paired with a Big Agnes Zoom UL mat and wearing nothing but base layers, for example, I felt warm enough in the Ascent down to 32°F (0°C). And when paired with a Sea to Summit Ether XT Extreme pad, the same base layers, socks and a Patagonia Nano Puff jacket, I slept through in temperatures of around 25°F (-4°C). But I wouldn’t push it further than that without doubling it up with a quilt.

Meet the reviewer

The Sea to Summit Ascent: fit

The fit of this bag is another thing I particularly liked. It’s tight enough to keep you warm, but wide enough that you don’t feel restricted. At 5ft 10in (1.78m), I had more than enough space in here to comfortably spend long fall and winter nights, and never felt as constrained or restricted as I have in other bags. Is it as free and as comfortable as something like a Zenbivy? Absolutely not. But it’s very comfortable for a mummy bag, and definitely up there as one of the coziest I’ve tried.

Overall, I think the Sea to Summit Ascent -9 is an exceptional bag. It’s super versatile and a joy to use, and is one of the only bags I’ve ever come across that can actually keep you comfortable in four different seasons. At $469 (US) / £450 (UK), it is frighteningly expensive for a bag of feathers, sure, but thanks to its versatility and the ease with which you can pair it with a quilt (if you’re happy to buy a quilt as well, that is), I think this bag serves as the basis for one of the most versatile four-season sleep systems out there. Which makes that initial high price easier to stomach.

• How Advnture tests products

Sea to Summit Spark SPII: first impressions

Sea to Summit’s Spark sleeping bags are the lightest and most packable in the brand’s entire range. Designed to deliver versatile warmth on adventures where weight and pack size are at a premium, they feature a stripped-back and minimal design that’s been created to deliver on that brief. The Spark SPII is the second lightest in the line, promising to keep you warm down to temperatures of around 38°F / 4°C.

To maximize weight and packability, Sea to Summit have filled this bag with super-lofty 850+ fill power down. The result is a bag that barely weighs 500g and packs down to the size of a one-liter Nalgene bottle.

To me, this makes it one of the lightest and most packable bags I've ever tested – if not the lightest and most packable bag I’ve ever tested. That status has come at the expense of quite a few sacrifices, however; the Spark SPII offers fewer features than many equivalent bags, while still costing a hefty $409 / £400 when bought directly from Sea to Summit.

Naturally, then, this bag isn’t one for the weekend warriors. It’s for multi-day fast packers and ultralight backpackers for whom grams are more important than pounds (or dollars). Is it worth this initial high investment, then? Or is it too minimal to keep you comfortable outdoors?

Sea to Summit Spark SPII: features

To make the bag so small and light, Sea to Summit have had to make a few sacrifices. Firstly, there’s no neck baffle, which is something I certainly missed on colder nights. Instead, a singular drawcord pulls everything in, which still does a great job of keeping in the heat.

Additionally, Sea to Summit have also done away with an internal storage pocket to bring the weight down further. To be honest, I was happy to see this omitted from this iteration as I never use them anyway, but it might be something worth bearing in mind if you’re a fan of keeping things close to your chest overnight.

Sea to Summit Spark SPII: insulation

In order to make the bag ultra-light and packable, Sea to Summit have used around 300g of 850+ fill power-down insulation in the Spark II. This is the second highest-lofting down used by Sea to Summit, and the result is a bag that’s super lofty, warm and impressively packable – noticeably more so than bags with a similar temperature rating that comprise lesser-quality down. As it’s treated with a PFC-free hydrophobic treatment, the insulation is also more water-resistant and faster drying than untreated down.

To protect that lofty down, the Spark II comes wrapped in a 10D nylon shell. Despite being super soft and comfortable on your skin, I also found that this does a decent job of keeping water out as long as you shake it off quickly and don’t give it a chance to soak in.

Sea to Summit Spark SP II: fit

In a move to further reduce the bag’s pack size and weight, the fit of the Sea to Summit Spark SP II is decidedly tight. To me, I found that this was a trade-off I was always more than happy to make thanks to the bag’s benefits in other departments. But if you like to move around in your sleep, you may find this too restrictive, especially if camping in colder weather and you need to zip it all the way up.

Meet the reviewer

Sea to Summit Spark SP II: in the wild

I first got my hands on this iteration of the Sea to Summit Spark SP II -2° way back in the summer of 2023. As I write this, I’ve used it around a dozen times on trips in various conditions, including two fastpacking trips, a handful of backpacking overnighters, some casual camps in local woodland and an early winter backpacking trip in sub-zero temperatures where I combined it with Sea to Summit’s Ember quilt. Over the last 12 months, it’s become my go-to bag when I need something light and packable for trips with a 25-45 liter pack.

The first thing worth noting about the Sea to Summit Spark SP II -2° is the very thing you’d buy this bag in the first place for: it’s tiny. Seriously, when packed up, it takes up about as much room as a down jacket or a water bottle, and weighs about the same as a loaf of bread. Despite that, it’s still perfectly capable of keeping you warm in some chilly conditions. During my months of testing, I’ve slept in this bag in just my running kit in temps hovering around 41-45°F (5-7°C), and have comfortably spent the night in when layered up in base layers down and a thin down jacket to around 37°F (3°C).

To make it extra versatile, however, the bag also comes with four toggles on the outside that allow you to fasten a quilt, known as Sea to Summit’s QuiltLock system. To test this, I paired the Spark with a -1°C Ember quilt on a chilly winter backpacking trip in Bannau Brycheiniog (the Brecon Beacons) where the temperature outside hit 19°F (-7°C). To my surprise, I stayed toasty warm all night in this combination, convincing me that this might be one of the most versatile four-season sleeping setups out there.

Granted, you’d need to punt for the additional quilt to make this work (which would make it one of the most expensive four-season sleeping setups, too!), but you end up with a versatile system that can keep you comfortable in everything from balmy summer evenings through to freezing winter nights – all for an amazing 900g.

Sea to Summit Spark SP II: the bottom line

Overall, I love the Sea to Summit Spark SP II -2°. To me, it’s the ideal bag for trips when I’m willing to sacrifice bells and whistles in favor of weight and pack size. That being said, it’s still super comfortable and a joy to use, and the added benefit of being able to pair it with a quilt makes it one of the most versatile ultralight sleeping setups for real four-season adventuring. Granted, at $409 / £400, all of that does come at a cost. But if you can afford it, I think the Spark II is hard to beat.

• How Advnture tests products

Rab Mythic 400: first impressions

The Rab Mythic 400 is part of the British brand’s premium sleeping bag range aimed at alpinists and backpackers who desire low weight and impeccable quality. It weighs in at less than 25oz, yet is packed with 900 fill power (FP) goose down that has been treated with Nikwax Fluorocarbon-Free Hydrophobic Finish in a bid to improve durability in harsh conditions. The range-topping materials do come at a cost; with a list price of $650 (US) / £560 (UK), the Mythic 400 firmly in the high-end category.

The bag is made with a recycled Atmos fabric shell, which is lightweight, windproof and highly water-resistant. The fabric is made from a 10D recycled nylon, and is waterproofed with a fluorocarbon-free DWR (Durable Water Repellent) treatment. This commitment to sustainability is becoming a key focus for Rab, with the manufacturer claiming that 38% of the bag’s materials come from recycled sources. The move away from traditional PFAS (perfluoroalkyl and polyfluoroalkyl substances) in favor of more eco-friendly alternatives is something to be applauded.

The Mythic 400 has a trapezoidal baffle construction which is chevroned in shape, which Rab say is all in aid of keeping the down more lofted during use. This results in a usable temperature rating of 21°F (-6°C), putting the Mythic 400 firmly in the three-season category. On the left side of the bag, you’ll find a half-length YKK zipper, which, while saving weight, can feel restrictive in terms of ventilation and accessibility. Similarly, the tapered design is intended to maximize warmth, but it may feel constricting for larger users or side sleepers. It’s worth noting, too, that the Mythic 400 is still only available in one size and one color.

Expectations were very high for such a pricey sleeping bag from a prestigious brand such as Rab, and it’s fair to say that they were all met or exceeded. Rab has put together a fantastic blend of warmth and comfort, all in an incredibly packable product.

Meet the reviewer

Rab Mythic 400: in the mountains

What better way to test a sleeping bag marketed at alpinists, than by taking it to the home of alpinism? I deployed the Mythic 400 in multiple wild camps in Switzerland this summer – mostly in a tent – and several were at fairly high altitudes by European standards.

Sleeping temperatures ranged from just above freezing to around 50°F (10°C), and I never once felt the chill. The lofty 900FP down provided exceptional insulation, so much so that on a number of occasions I ended up using the Mythic more as a duvet than a sleeping bag despite wearing only thin pajamas to bed! An occasion where things did get slightly more chilly was a bivy camp at around 7,500 feet. It was dry enough that I didn’t have to worry about rain, but I appreciated the windproof Atmos fabric as it shielded me from the fairly brisk alpine air.

A note on size too – I was completely cocooned in my sleeping bag. I’m 6’0”, and fairly broad, and I was pretty comfortable in the bag. The one size is fairly roomy, but this could make it tight for those much larger than me, and potentially not as warm for those a little smaller. That said, I think Rab have done a good job at servicing as many people as possible for a specialist product where production numbers will be lower.

However, as temperatures climbed into the 40°F (4°C) range, the Mythic 400’s half-length zipper did become an issue. The short zipper prevents efficient venting, which could make the bag feel stuffy in warmer conditions. This must be caveated by the fact that this is a sleeping bag for extreme conditions. The only real snag, quite literally, was that the smaller YKK zipper did have a tendency to catch on the baffle that runs lengthways on the sleeping bag. It never caused the material any harm, but certainly something to be careful of.

Put the Mythic 400 in your pack, and you can pretty much forget about it. It compresses down to a modest 13.8in x 9.1 (35cm x 23cm) in the included compression sack. It’s a premium stuff sack too – a dry bag-style sack that’s totally waterproof to protect your pride and joy should the rain really start to come down, or you have a dreaded backpack spill.

As for durability, the Rab Mythic 400 held up well despite being subjected to rocky terrain during wild camps. While I did take care not to abuse the bag, the thin 10-denier shell fabric showed no significant wear after weeks of use. The DWR treatment kept moisture at bay, but like all ultralight gear, this bag is best used with a bit of caution to avoid snags or tears.

• How Advnture tests products

Meet the reviewer

Lifeventure Cotton Sleeping Bag Liner: first impressions

A good sleeping bag liner is far more than a mere adventure accessory or a little luxury. Used correctly these seemingly simple pieces of kit have myriad applications. They can vastly improve your levels of comfort while camping, by effectively upping the temperature rating of your 2-season or 3-season sleeping bag in the colder months (and reducing the amount of times you need to wash your down bags), or by working as a stand-alone cover in the height of summer. And when you’re staying in alpine huts or traveling internationally, they can be an absolutely essential (many huts and hostels insist you use them).

However, like everything you take camping with you, such a piece of kit has to earn its place in your hiking backpack by proving that it’s worth its weight and pack space. This cotton sleeping bag liner from British brand Lifeventure comes with its own stuff sack and, while it’s far from the lightest liner on the market, it’s very neat and easy to slide into any kind of bag, including a large daypack (which I often use for one-night escapades and hut-to-hut hikes).

When it first arrived I was impressed. With an inbuilt pillow sleeve and the fact that it’s been treated with Polygiene, it promised to be super useful in both camping and traveling situations. These features – coupled with a very accessible price tag – meant this liner looked like a piece of equipment well worth adding to my kit cupboard. But how would it perform in the field and on the road? I put it to the test while camping and traveling to find out how it compared to the best sleeping bag liners on the market.

Lifeventure Cotton Sleeping Bag Liner: design & materials

Made from cotton, this liner is available in both mummy and rectangle designs, so it can be used with pretty much any sleeping bag. But while there are two shapes to choose from, they each only come in one universal size, which people at the taller and smaller ends of the height spectrum may find inconvenient. 

The design includes a pillow cover, which helps with hygiene and also keeps your sleeping setup together (if you’re prone to tossing and turning). It comes with its own ripstop stuff sack, which rolls and clips shut like a dry bag, and although it doesn’t promise to be waterproof, this is handy for keeping the liner clean and compact, and it has a hanging loop, which can be useful too. 

The cotton used is standard (not organic) and it is dyed, so the liner does have a sizeable eco footprint. That said, the material has been treated with Polygiene, which means the liner has inbuilt antibacterial and odor-busting properties, so you won’t have to wash it too often (which is better for you and the environment). Being made from cotton, it’s easy to launder when you do decide it requires a refresh. It’s essential to make sure the liner stays dry on the trails because cotton has no thermal properties when damp.

Lifeventure Cotton Sleeping Bag Liner: in the field

I’ve been using this liner while camping and traveling over the last few months, as a stand-alone sheet on balmy nights (when it really excelled) and as an extra layer as summer segued into fall and the outdoor temperatures rapidly dived. It has also come in very useful on some travel trips too.

It has helped keep me nice and snug on some cold nights (especially in those chilly pre-dawn hours). I love the fact that I can climb into this liner straight from the trail – with muddy legs – and my sleeping bag will stay pretty clean. It’s really easy to launder the liner, but washing sleeping bags is much more of a pain. 

It isn’t the lightest liner on the market, but neither is it overly heavy, and the excellent, highly protective stuff sack makes it very easy to pack and carry. I find the integrated pillow case really useful, both for giving me peace of mind when traveling and using pillows that have had many heads on them before mine, and also for stuffing full of fleeces and puffer jackets when I’m lightweight camping and improvising a pillow. On occasions when I have taken a camping pillow with me, the integrated case is good for keeping the pillow in place in my sleeping bag. 

• How Advnture tests products

Nemo is a brand that doesn’t bring anything to market unless it’s an improvement on what’s already out there. In the case of its newest synthetic Forte sleeping bags, it took its original design and gave it a sustainable overhaul, crafting a cozy cocoon of recycled materials that's also 100% recyclable at the end of its life too. The launch officially kicked off the brand’s Endless Promise collection in 2023.

So, keeping in step with the likes of Patagonia and Rab, Nemo has got its eye on the full lifespan of its products. The Forte Endless Promise bags are constructed from a single type of material, which makes it much easier to recycle and goes a long way to keeping waste out of landfills.

I was stoked to test this environmentally friendly, 3-season sleeping bag in the backcountry to see if its performance is as strong as its green credentials.

First Impressions

When I first clocked the Forte in its compressible stuff sack, it was apparent that it wasn’t the most packable sleeping bag in town. If you’re looking for an ultralight, uber-packable sleeping bag, ideal for long, multi-day backcountry expeditions or summer thru hikes, this isn’t the bag for you. However, this is hardly surprising given its modest price point and the fact it features synthetic insulation, rather than down. It weighs 1.64kg / 3lb 10oz, which is on the heavier side of things, and it doesn’t pack down as small as the best in the business. If ultralight kit is your thing, you're set on a Nemo bag and you've got cash to spare, check out the more expensive Nemo Coda.

Nevertheless, once I unclipped the stuff sack and liberated the Forte, I quickly appreciated its quality. The soft polyester inner feels lovely against the skin and clever features, such as the Thermo Gills and pillow pocket, hint at the careful consideration that’s gone into the design.

Recycled, recyclable fabrics

There’s a lot to shout about when it comes to the recycled main fabrics, which are bluesign approved, as well as fully recyclable thanks to their mono-polymer construction. The shell is a 30D ripstop polyester, while the plush lining is a 20D polyester taffeta. Taffeta, usually made from either silk, polyester or nylon, is a shiny, crisply woven fabric often associated with high fashion. Here, it lends comfort to the Forte’s its luxurious inner sanctum, your soft cocoon for happy slumbers.

In between these layers is the post-consumer recycled synthetic fill, which maintains its loft beautifully and retains its thermal qualities when wet – an oft-stated advantage of synthetic insulation over down.

Thoughtful features

One of the Forte's most striking features is its profile. Rather than the traditional mummy form, it has what Nemo call a 'spoon' shape. I don’t know what Nemo’s marketing team have been eating, but it doesn’t look that much like a spoon to me. I’d have called it an hourglass shape: it’s widest at the shoulders, tapers a bit in the middle, widens again around the hips, before tapering significantly at the footbox. This shape provides an unrestricted sleep, allowing side sleepers to shuffle around in comfort, with more space at both the shoulders and knees.

There’s plenty going on around the head, with a cinchable hood, draft collar and a compartment for a camping pillow. When the temperatures plummet, the draft collar can be tucked in to provide a shield against the cold, while the hood can be brought in tight.

Speaking of cold, the bag is suited to 3-season use, with a Comfort rating of -1°C / 30°F. I camped in temperatures of around 5°C / 41°F and found the bag to be nicely warming. There's no doubt that it could have the potential to be overly warm in really hot conditions, which is why Nemo employs two Thermo Gills on the front towards the top. These are zippered openings that reveal a thin panel of the inner fabric that allows radiated body heat from inside and ambient air from outside to bypass the insulating layer, allowing the sleeping bag to breathe and cooling the wearer down.

Down the left side is the almost full-length zipper with anti-snag guard, which can be opened from both the interior and the exterior. The footbox has a couple of loops for easy hanging when storing, airing or when you need to wash your sleeping bag and dry it afterwards.

When it’s time to pack it away, there’s a stuff sack armed with compressions straps that can be tightened for transportation. However, don't forget that the best way to store a sleeping bag is to hang it up, if you have the space.

In the field

I used the Forte during summer car camping trips and for a backpacking expedition in the English Lake District, where I was able to fully test its 3-season credentials during a chilly summit camp. I’m still alive, so it must have done something right.

In fact, it did more than that. I found sleeping in the Forte a very pleasant experience throughout. Comfort is what this bag does best and its spoon shape means that it’s less restrictive than many other bags. I never got that awful, claustrophobic feeling you sometimes get when the sleeping bag says “no”, as you try to turn in the night and you have to wriggle a bit to free yourself back up from fabric that has coiled around your legs like a polyester anaconda.

During warm summer nights at sea level, the Thermo Gills allowed me to cool things down and I really appreciated their presence. They were then fully closed up during my mountain camps. Meanwhile the ability to cinch things in tight and utilize the draft collar allowed me to lock precious heat in during what would have otherwise been quite a brisk wild camp.

So, there’s nothing wrong with wild camping with the Forte, though it does take up quite a bit of space in a backpack and, as mentioned, there are lighter alternatives out there. It's definitely something to consider if you're intending to take on a load of elevation gain to access a hard-won, remote wild camping spot.

To begin with, I was unable to fit my Nemo Fillo pillow into the pillow pocket! However, any frustration was short lived, as I realised the answer was to insert the pillow pre-inflation and then blow it up once in situ. The tight gap that had stopped me inserting the inflated pillow to begin with was now the same one keeping it in place. Ideal! I approve of this feature, as it stops the pillow moving around or slipping out from under my head. This had been a qualm I’d had with the otherwise superb Nemo Tensor Extreme Conditions Ultralight Sleeping Pad, as the pillow would slide along its smooth surface like a greased eel.

The stuff sack is well designed. On the bottom is a large fabric loop for carrying or for pulling in the opposite direction liberating the bag from the sack. The compression straps are easy to pull tight or loosen, while getting the bag back in the sack isn’t a struggle.

Colder weather is on the way and right now, you can get your hands on The North Face Trail Lite Down 20 Sleeping Bag for just $137.73 at REI.

That's a whopping savings of 40% off the list price on this cozy mummy-style sleeping bag, which is billed as lightweight and packable yet surprisingly warm.

With 600-fill-power recycled down, this sleeping bag is warm enough for outdoor sleeping through the colder seasons and delivers a high level of compressibility for all-season backpackers.

A fully insulated hood with an insulated cinch collar seals out chilly drafts and helps keep your head warm while you snooze, and the addition of synthetic fill around your toes limits compression where you need extra warmth.

This deal applies to both the regular and extra-long sizing in the Blue Coral/Reef Waters colorway but if you're interested, you should act now as this model has been discontinued. 

If you're not in the US, scroll down to the bottom of this article for today's best deals on some of our favorite 20-degree sleeping bags near you.

If you're not in the US, here are today's best deals on some of our favorite 20-degree sleeping bags near you:

• The best sleeping bags 2024: for comfort in camp

Sleeping bags are kind of an essential camping item, I’m sure you’ll agree. After a long day of hiking with a heavy backpack, there’s nothing better than crawling into a cozy sleeping bag, zipping it up and drifting off under the stars. 

As a frequent camper, I never thought I’d see the day when I’d forego my trusted GoLite sleeping bag that’s kept me warm all over the Rocky Mountains and some of America’s best National Parks – but over the last couple of years, that’s exactly what has happened.

Two summers ago, I got my hands on the Sea to Summit Ember II Down Sleeping Quilt to test out on my nocturnal adventures. If you don’t know, a camping quilt typically has no zip or hood, but it provides more protection than a simple camping blanket. It is made using the same fabric and insulation as a sleeping bag and has a foot box that encloses around the bottom of your sleeping pad, while some have straps that wrap around the pad too. 

After making sure I was happy with mine while camping near home on the banks of Loch Lomond, I took it on a thru-hike of the West Highland Way and I loved it. Since then, I’ve camped through all four seasons in several different countries and used it every time. I even lent it to a friend who was traveling to India for a month and wanted to keep her bag light but needed to feel confident she’d have enough insulation at altitude. 

Honestly, I don’t think I’ll ever go back to using a traditional sleeping bag, unless I’m heading to the Arctic where some serious protection is needed. I have the 35°F version, which you can still find using the link at the end of this article, while these days the Aussie company makes it in 30°F/45°F and regular and long.

Curious? Here are three reasons why I love my camping quilt more than my sleeping bag, and why you might want to try one too.

1. It saves on weight and valuable space

Because a camping quilt has less material than a traditional sleeping bag, no hood and no zip, it should come as no surprise that it’s way lighter. This may not matter to you if you’re a dedicated car camper (though I recently wrote about bringing mine car camping too, and I still prefer it), it’s a huge deal if you’re backpacking or traveling.

I’m not talking about saving an ounce or two either – my camping quilt is literally half the weight of my sleeping bag, which itself is quite light at only 2.3 lbs, and packs down to half the size as well. Whether I’m backpacking or traveling by plane or train for an active adventure, it means there’s plenty of room for all my gear and my bag is easy to wrestle into an overhead locker or haul up a mountain.

2. I can better regulate my temperature

When you think about camping, you might understandably be worried about staying warm enough at night and having lived at high altitude for many years, I appreciate that. For people like myself who camp in different seasons and climates, however, it’s just as common to wake up too hot as it is to feel cold, so what I really want is insulation that helps me regulate my temperature so I’m not spending half the night pulling on extra clothes and the other half unzipping my bag.

In researching camping quilts and sleeping bags, one of the important things I’ve learned is that since most insulation works by trapping air, when the weight of your body is pressing down on your sleeping bag, there isn’t much air to trap. In fact, most of the insulation is being provided by your sleeping pad anyway, so that layer of fabric that’s missing from a quilt usually isn’t essential. 

Furthermore, my quilt has both a foot box and optional straps to cinch it tightly around my pad, so even when I did some unusually cold early spring camping in Yosemite National Park a couple of years ago, I was able to stay quite snug, just pulling on a beanie hat and wool socks to stay warm. Meanwhile, when I was camping in warm weather this summer, the fact that I wasn’t cocooned meant my sleep system was much more breathable and I wasn’t overheating while my tentmate in a sleeping bag was.

3.  I’m actually comfortable in any position 

I might love camping, but like anyone else I can struggle to get comfortable at night, especially when I’m spending multiple nights in a row out in the wild. Sure, it’s partly to do with sleeping on the hard ground, but my Therm-A-Rest ProLite Apex sleeping pad is really pretty plush. 

It turns out that the biggest obstacle for me is that, as a somewhat dynamic sleeper, I have a hard time finding a comfortable position when I’m swaddled inside a bag. My legs are bound together and if I free my arms they get cold, and there always seems to be a cold, hard zip in my face.

Not with my camping quilt, however. Because it doesn’t restrict my limbs, I’m free to sleep in all of my favorite positions – starfish, freefall, on my side – without having to wake up and reorganize my entire sleep system. There’s no annoying zip and nothing to keep me from sleeping in whatever position I want. Well, except for my tentmate that is.

• The best camping pillows 2024: tested for comfort in the backcountry

Right now, you can pick up the top-rated Mountain Hardwear Phantom 0 sleeping bag for 35% off at REI. That's a whopping savings of $240 off this impressively light and warm bag. 

If you're not in the market for such a warm sleeping bag, the Mountain Hardwear Phantom 30 is also slashed by 35%, however that deal only applies to the long version of the bag, which is 78 inches compared to the regular length of 72 inches.

The Mountain Hardwear Phantom 0/-18 is the flagship sleeping bag in the Mountain Hardwear line. As its name suggests, the Phantom 0 offers warmth down to a bone-chilling 0°F. Yet, given its four-season capabilities, it is lightweight and compact, with an impressively small pack size that ranks among the best in this class. Though we found the fit to be quite snug in our field tests, that's exactly what you want when the temperatures drop.

It is filled with a hefty 850g/1lb 14oz of 850 fill power down, housed in either a Pertex Quantum or Gore-Tex Windstopper fabric shell. However, all good things must come to an end and the brand has discontinued this model. REI still has some in stock, but is obviously keen to make space in the warehouse with this tempting offer for anyone planning on winter camping or mountaineering this year.

If you're not in the US, scroll down to the bottom of this article for today's best deals on the Mountain Hardwear Phantom 0 sleeping bag where you are.

If you're not in the US, here are today's best deals on the Mountain Hardwear Phantom 0 sleeping bad where you are:

• The best sleeping bags: for comfort in camp

After a long day of backpacking, it’s easy to drift off to sleep, cozy inside your best sleeping bag, but when summer rolls around, you might soon find yourself awake and annoyed if you’re a little too warm. You can unzip your bag but then you might get too cold. If you’re using a sleeping bag liner, however, there’s no problem – just unzip and enjoy some light protection thanks to the breathable layer underneath it. 

As the temperatures heat up, you might be wondering if next time, you can forgo the bag altogether and just use your sleeping bag liner on its own? With so many backpackers keen to shed weight these days, it’s a good question and one we hear a lot. 

But can you ditch your insulated bag for warm weather camping, and just rely on a liner? We dive into this camping question to help you make the smartest decision on your next outdoor adventure.

Can you use a sleeping bag liner on its own? 

Assuming you’re talking about using a sleeping bag liner for camping in a tent, where you’re more vulnerable to the elements than indoors, it’s important to understand the importance of your sleeping bag. 

Whether it’s made using down or synthetic insulation, your sleeping bag is intended to keep you warm by holding your own body heat close to your body. If it’s going to be cold overnight, this is crucial for your safety, though it’s also helpful to remember that your sleeping pad also goes a long way towards keeping you warm by protecting you from the cold ground.

If you’re camping in a region with a more temperate climate, at high altitude or in the desert, even if it’s warm during the day it can still drop down to the 30s and 40s overnight and you’re going to need insulation, which a sleeping bag liner on its own won’t provide. If you’re camping at the Lake of the Ozarks in July, you might be looking at overnight lows in the 60s. Still not exactly hot, but if you’re a warm sleeper you may think you’ll be comfortable enough with a liner and you could be right.

If you’re not sleeping inside a tent or other structure that blocks the breeze, also known as cowboy camping, you’ll also want to keep in mind that one of the best qualities of sleeping bag liners – their breathability – will mean that there’s not much  to protect you from cool moving air.

Ultimately, if you’re camping in hot weather and using a tent, you may be quite comfortable with just a sleeping bag liner, and ditching the bag can help you shed quite a bit of bulk and weight. However, it’s important to do your research and check the weather forecast first, ensuring you understand what the overnight lows are expected to be in the exact area where you’re going. Remember that temperatures always drop as you go up in elevation. 

To be safe, you might want to bring a lightweight camping blanket like the Rumpl NanoLoft Puffy Blanket for backup, which is much lighter than a bag but will keep you warm if you wake up in the night and realize you’ve misjudged things. The smartest move would be to test it out first in a safe environment – like your own backyard or with an exit plan in mind – before bidding your insulating layer farewell.

• 7 reasons you need a sleeping bag liner

Meet the reviewer

Sea to Summit Reactor sleeping bag liner: first impressions

When I received the Sea to Summit Reactor sleeping bag liner, I first wondered whether it would really be a necessary piece of kit.

Usually, a sleeping bag liner isn’t something I’d routinely update, seeming such a perfunctory piece of kit, necessary only for backpacking on multi-day adventures or traveling around bedbug-ridden hostels to avoid sleeping under suspiciously old bedding. But when I tested the Reactor liner, valley camping on the cold floor of a campsite in the Dolomites, wild camping in Ireland on a breezy coastal path, and on an expedition below the north face of a peak in Tajikistan, I noted just how relieved I was to have an extra insulation barrier to keep warm. 

Out came the sleeping bag liner – no fuss or extra faff other than slipping myself inside with a hood to flip over the top of my head, and easily adaptable to my mummy-shaped sleeping bag. The sleeping bag liner also eliminated the dreaded ‘cold pocket’ feeling that sometimes happens if like me you’re smaller than the average man the sleeping bag is built for, so it makes a massive difference to the overall comfort factor.

Sea to Summit Reactor sleeping bag liner: on the trails

First things first, the Sea to Summit Reactor sleeping bag liner is compact and easy to store. It comes in a little drawstring pouch so it can be easily packed away. This takes up very little space – around the size of an apple. It’s super handy when every gram and inch of packing space is crucial, as the sleeping bag liner easily folds away and can even be tucked inside your sleeping bag, meaning it’s less likely to be forgotten about.

Sizing wise, it fits most sleeping bags, and newer models have a drawstring opening at the top and bottom to make visits to the loo easier – so you can keep the liner on and hitch it up for emergency toilet breaks without loss of heat from the body. It also allows sleepers who need more room to stretch the option to have their arms outside of the sleeping bag liner.

The Sea to Summit Reactor sleeping bag liner uses several different fabric technologies to help it keep fresh for multi-day use. HeiQ Fresh odor technology doesn’t rely on harmful chemicals such as biocides, nor does it contain any silver like Polygene. Treating the fabric with a bio-based Amino Sugar Polymer, the HeiQ is a clever chemical that controls odor build-up by neutralizing it. It permanently binds smelly molecules without affecting the fabric’s breathability, color, feel or wicking properties. This means the liner requires less washing, which overall is better for the environment, and is a much more practical sleeping fabric than standard cotton.

The Reactor liner also uses a cleverly engineered fabric known as Thermolite Pro. This is easy to move in, feeling like a comfortable fabric you’d want to fall asleep against, thanks to its knitted construction which yields great stretch and freedom of movement. The hollow core fibers have infrared-absorbing ceramic pigments that reflect body heat back in for greater heat retention. The fibers have also been recycled from 100% textile waste, and are GRS-certified, yet offer the same quality and durable lightweight warmth as their polymer virgin counterparts – just with a lower carbon footprint.

It’s really a no-brainer to carry a warmth-retaining sleeping bag liner. There are many ways to retain heat while wild camping – a decent insulation setup from the ground using a good sleeping pad, a carby meal at dinner, and use of a good hat to keep heat loss at bay all help. But for an extra guarantee that the night’s sleep will be a cozy one, the Reactor sleeping bag liner offered great peace of mind that I would stay as warm through the night as when I first got into the sleeping bag, and would wake up well rested.

• How Advnture tests products

For serious adventurers and avid campers, a quality sleeping bag is a no brainer. It’s arguably the most important component of your camping kit, enabling you to sleep warm in the wild, rest comfortable in the cwms and laze happily by a lake. If you’ve invested in a lightweight sleeping bag, you’ll know that it’s worth its weight in gold for its portability, warmth and performance in the great outdoors.

However, the best sleeping bags, particularly those filled with down, take quite a bit of effort to care for. Over time, dirt, sweat and body oils work their way into the fabrics, diminishing the loft and compromising its ability to insulate effectively. Washing a sleeping bag requires specific products and a very delicate wash cycle, while drying the bag properly out can take several days. In short, it’s a bit of a faff, particularly if you don’t have much time between your adventures.

What if there was a product that not only enhanced the comfort, warmth and performance of your sleeping bag, but also protected it as part of the bargain too? Enter, the sleeping bag liner, a simple yet elegant solution. There are many reasons you need a sleeping bag liner, so let’s get into our main ones…

Meet the expert

Today's best deals

What is a sleeping bag liner?

• A sleeping bag liner is a lightweight sack that slots into a sleeping bag
• They provide additional warmth, comfort and protect your sleeping bag
• They’re typically made from either silk, polyester, polyamides, fleece or polycotton

A sleeping bag liner is a lightweight, sleeping bag-shaped sack that’s designed to slot inside your bag, providing an additional layer of material. The advantages are many: a liner gives additional warmth and comfort, while also providing a protective barrier for the lining and insulating fill of your sleeping bag. Better still, they’re machine washable after use, which makes them easy to look after.

Sleeping bag liners are usually woven from either silk, microfibres made from polyester or polyamides, fleece, cotton or polycotton – which, as its name suggests, is a blend of polyester and cotton. Silk sleeping bag liners tend to be the most expensive, though they’re also luxuriously lightweight, soft against the skin and provide a good level of protection for your sleeping bag.

Let's get into the reasons you need a sleeping bag liner...

1. To protect your prized cocoon

• Liners protect your sleeping bag from dirt, sweat, damp and body oils
• This extends the lifespan of your sleeping bag

You want your sleeping bag to last as long as it can. For many, the main benefit of a sleeping bag liner is that it protects your bag from grime, sweat, body oils and damp by providing an additional layer of material. This, to a lesser extent, also protects the bag’s lining from getting torn by a rogue multitool or key.

Why is this so important? Well, at the time of writing, the bags in our best sleeping bags buying guide range from around $100 (£80) to a whopping $760 (£570), while a dedicated 4-season sleeping bag may set you back even more. So, it’s fair to say a quality sleeping bag is quite an investment and one that you won’t want to be repeating all too often. By using a sleeping bag liner, you extend the lifespan of your bag.

As well as the monetary cost, there’s also the environmental and ethical cost involved with sleeping bags. Neither down nor synthetic insulation is perfect in this regard. A down sleeping bag is filled with natural down plucked from ducks or geese and practices in some places are cruel to say the least. Admittedly, brands are increasingly aware of ensuring that the down used in their products is sourced ethically, but it’s still an imperfect picture. Meanwhile, synthetic fill, usually made from polyester, will never biodegrade, and has a habit of leaching microplastics when washed, which end up polluting the world’s oceans.

For the purpose of balance, it’s worth noting that liners aren’t necessarily perfect either. Many are made from similar synthetic materials, while silk is produced by boiling silkworm cocoons with silk larvae inside. Cotton liners are perhaps the most ethical choice.

2. They're easy to clean

• Unlike sleeping bags, liners are easy to launder and dry

We’ve already established two key points here. Firstly, sleeping bags are a bit of a faff to clean and to dry afterwards. Secondly, synthetic sleeping bags leach harmful microplastics that work their way into our watercourses and end up in the ocean. In an ideal world, you want to wash your sleeping bag as little as possible through the course of its life.

The good news is that your wonderful liner has taken all the hits, soaking up all the grime, body oils and sweat (possibly blood and tears too, if you’re trip was particularly gripping) from your adventures. Simply remove your liner from your bag and when you get home, pop it in the laundry – most are machine washable with standard detergent. Not only this, unlike a sleeping bag, they dry just as quickly as the rest of your washing. Job done.

3. It’s luxuriously soft

• Silk sleeping bag liners are wonderfully soft against the skin and breathable too
• Synthetic liners are also designed to provide enhanced comfort

As well as protection, sleeping bag liners provide enhanced levels of comfort. Undoubtedly, the most luxurious are those made from silk, which are gloriously cozy and soft against the skin. Not only this, they tend to be more breathable than other liners, perfect for those summer camps.

However, it’s not just silk liners that add an element of comfort to your slumbers. Synthetic liners are also designed to be highly breathable and moisture wicking, as well as being pleasant against the skin too. Hybrid materials, such as polycotton, are also comfortable to lie on, while being more durable than standard cotton. Whatever you choose, it’s likely that a liner will feel better against the skin than your sleeping bag’s inner fabric.

4. Additional warmth for cold camps

• A fleece liner provides insulation for cold season camping
• Depending on various factors, a liner can add between 5°F to 25°F of warmth

Different kinds of sleeping bag liners offer different levels of warmth. A fleece liner will be far more insulating than a silk liner for example. Regardless, anyone who’s familiar with layering will know that more layers equals more warmth. So, a sleeping bag liner is a particularly wonderful thing for winter or shoulder-season camping, when you might need every additional degree of heat to make for a comfortable night’s sleep. Depending on the design and materials, a liner can add between 5°F to 25°F of warmth to your sleeping system.

That’s not to say you shouldn’t take a liner with you for summer adventures. The reasons I’ve already given should be enough to convince you that they’re a great help all year round. However, if you’re heading for the desert in July, you’d be better served by a thin silk liner than a beefy fleece one.

5. It weighs next to nothing

• Sleeping bag liners are very light and take up very little space
• They’re worth the additional weight for all the benefits above

Hauling camping gear through the backcountry can be a testing experience. While kit these days is lighter than ever, even a one-night expedition can render your hiking experience to something akin to a yak’s, doggedly lugging your load up to a chosen basecamp. Why, then, would you want to add something that’s arguably not absolutely essential? 

Well, a sleeping bag liner can weigh anything between 100g and 1kg, though most tend to be towards the lighter end of this scale. Silk, polyester and polycotton liners weigh next to nothing and take up very little space in your pack. We’d argue that, for all the reasons given above, having a liner is worth every extra gram. Even hauling in a bulky fleece liner, which is likely to be on the heavier end of the scale, is worth it for the additional warmth on winter camps.

6. A breezier alternative for hot nights in camp

• You can use a sleeping bag liner on its own on hotter nights
• When used with a bag, you can open things up if you get hot in the night

Just as you wouldn’t wear your best down jacket in the blazing June sun, you probably won’t want to snuggle up in your insulated sleeping bag when a summer heat wave washes across the backcountry – not unless you want to lose half your body weight in sweat. 

This is when a sleeping bag liner can be used in isolation, providing a comfortable cocoon without hoarding every bit of heat you expel. If the forecast predicts balmy nights ahead, leave your bulky bag at home, thus shedding a load of grams from your pack, and head on out there.

If you're sleeping in both your bag and liner and get a little stuffy during the night, you can always peel back your bag to cool down, just like unzipping a layer while hiking.

7. You’ll need one for that hut-to-hut trek

• Many mountain huts insist on the use of a sleeping bag liner
• Hut dorm rooms tend to be very hot in the night – a liner is a cool option

If you’re embarking on a hut-to-hut trek or you’re hiking up to a refuge before striking out to an alpine summit, you’ll need a sleeping bag liner, which are even referred to as ‘hut sleeping bags’ by some. This is because they’re mandatory kit, insisted upon by mountain huts across Europe and the US for hygiene reasons.

Of course, you could carry an all-singing, all-dancing sleeping bag. However, the shared dorm rooms in mountain huts tend to get a little stuffy at night thanks to the radiated heat of dozens of slumbering hikers and mountaineers. Unless you’re rocking up to a deserted refuge in the dead of winter to use the dedicated off-season facilities, you’ll be better served by a cotton liner or similar.

Are you excited about spending nights out in the wild? You’re going to want to make sure you have all the best gear now camping season is here. First, a tent that can protect you against wind and rain but is easy to pitch. Next, a sleeping pad that inflates easily and keeps you comfortable even though you’re lying on the hard ground. Finally, you want to unroll a soft, cozy sleeping bag that provides warmth and breathability while you sleep.

Choosing the right sleeping bag is essential for spending a blissful night under the stars. It needs to be the right shape and size, warm enough but not too warm, packable and light, and there are so many great bags to choose from these days.

When you start shopping for a new sleeping bag, however, you might find the amount of information on the label a little overwhelming. What is fill power? Compressed volume? And what’s the difference between temperature, comfort, and lower limit ratings? Let us take all the work out of things and help you decode the label on your sleeping bag, so you know exactly what you’re getting for your money, and make sure it’s the best choice for your upcoming adventures.

Gender

Most sleeping bags will indicate whether they are designed for men, women or are unisex. You don’t have to shop by your gender, but it is helpful to understand that between men’s and women’s bags, there are some differences. Men’s sleeping bags are usually a bit longer, while women’s are often warmer, which assumes that women are cold sleepers. Learn more in our article on women’s vs men’s sleeping bags.

Shell/lining

The shell of your sleeping bag is the outer material and the lining is the inner material, and together this is what your skin comes into contact with while you’re sleeping. These are nearly always the same material, though you can find bags with synthetic shells and cotton lining, so it’s worth checking. There are flannel sleeping bags, which can be great for car camping, but for light backpacking gear, you’re almost always going to see that the shell and lining is made using either nylon or polyester. 

These two fabrics share a lot of the same properties and are both good options. Nylon, however, has that really silky feeling whereas polyester can be slightly rougher to the touch. Nylon can be constructed to be more lightweight than polyester and has better resistance to fungi and mildew. Polyester, meanwhile, is extremely durable against abrasion and heat, and dries a little faster than nylon if it gets wet on your adventures.

Both of these fabrics can be pretty breathable, but if you’re looking for something that’s ultra-breathable and soft against your skin, and weight is no object, cotton is actually the best choice – just don’t let it get wet.

Fill 

Fill refers to the type of insulation inside your sleeping bag, and it will either be down or synthetic. Down, usually goose or duck, offers the best warmth-to-weight ratio and is really light and packable, however it’s not as durable and won’t insulate well when wet. Meanwhile, synthetic down is heavier and bulkier (though it’s getting lighter every day) but will keep you warm if it gets wet and is hardier. There are also ethical concerns between the two, which you can learn more about in our article on down vs synthetic insulation, and it’s important to look for ethically sourced down or recycled synthetic fill.

Fill power

You’ll typically see a fill power rating on your sleeping bag between 300 and 900. Fill power is a little complicated, which is why we wrote a whole article on it, but in short, fill power describes down’s ability to fluff back up after being compressed – the more it can fluff up, the more air it’s able to trap which means more heat provided for your body. That said, how warm a bag is also depends on the quantity of down, which isn’t often on the label, and to understand that, you’ll want to read on for temperature, comfort and lower limit ratings.

Temperature rating

Not all sleeping bags will show a temperature rating, but if yours has an  “ISO” or “En” temperature rating, it refers to the temperature range at which the bag will work best. It’s important to know that this is calculated in a lab setting, and should be considered a guesstimate at best. To determine the temperature rating of a bag, it is tested with a dummy in standard conditions, such as wearing the same base layers and at the same temperature. 

This scenario doesn’t account for all the possible variables, such as what clothes you’re actually wearing, the R-value of your sleeping pad, the outside temperature and whether you’re a warm or cold sleeper, so you’ll want to make sure you also check the comfort rating. 

Still, if you’re looking for a bag for specific conditions, such as summer or winter, it’s a good idea to check the temperature rating as a baseline, so you don’t end up camping in zero-degree weather in a bag rated for 30F conditions.

Comfort rating 

The comfort rating on a sleeping bag is the rating that’s more commonly used on women’s sleeping bags and it indicates the temperature at which you’re likely to be the most comfortable, rather than the minimum or maximum temperature at which the bag should be used. This can be quite different to the temperature rating – for example, when we tested the Therm-a-Rest Parsec 0F/-18C, we discovered that while its temperature rating is 0F, its comfort rating is actually 14F. 

If you’re planning on camping outside of summer or at higher elevations, it’s vital to research what the lowest temperature you might sleeping in could be, then make sure the comfort rating of your bag is a little higher than that for safety.

Lower limit

Complicating matters further, your sleeping bag may also display a lower limit rating, which is a little more common on men’s and unisex sleeping bags. This indicates the lowest temperature at which the user might still be comfortable, and you’ll notice this is usually a lower temperature than the comfort rating on a women’s bag.

Compressed volume

If you’re hiking to your campsite, your sleeping bag is going to be stuffed inside a compression sack so that you can carry it, and you’re going to want to know just how much space it will take up. Most sleeping bags will display their compressed volume, in liters, which might not sound too intuitive, but it’s actually quite simple. 

If your bag has a 5-liter compressed volume and you’re hiking with a 50-liter backpack, it’s going to take up around a tenth of your available space, but only in theory. In practice, your backpack volume does include all pockets and compartments, so it’s not quite that precise, but it gives you a starting point to work from.

Shape

There are various shapes of sleeping bags available, with the primary two being rectangular and mummy bags, followed by sub-types such as double, quilts and zipless. Mummy-style bags are the most popular these days, because they’re lighter and draft-resistant, while rectangular bags are less restrictive and great for side sleepers. Learn more in our article on the different types of sleeping bags.

Zipper location

You probably don’t need us to explain what this means, but you may not understand the significance of whether your sleeping bag zipper is on the left or right side. As we explain in our article on sleeping bag zippers, your choice probably has less to do with your dominant hand and more to do with how ambidextrous you are and whether your sleeping bag shape, your body mass and your general level of contortionism give you room to move. Choosing the wrong one could be really annoying, so consider trying a few before you splurge.

• Best sleeping bag liners: cozy inserts

Meet the tester

Therm-a-Rest Parsec 0F/-18C sleeping bag: first impressions

The Therm-a-rest Parsec 0F/-18C sleeping bag is a deep-winter down bag that promises to keep you toasty warm at a chilly -10°C (14°F).

Weighing in at an impressive 1.09kg in the regular version and jam-packed with 0.74kgs of high-quality 800-fill power down, the Parsec 0F offers one of the best warmth-to-weight ratios of any sleeping bag on the market right now. 

What’s more, it packs down really small, lofts up quickly and is an incredibly cozy place to while away long winter nights in your tent. 

That being said, coming with a list price of $529.95 (US) / £550 (UK), this top-quality performance doesn’t come cheap. So is the investment worth it?

Therm-a-Rest Parsec 0F/-18C sleeping bag: in the wild

To properly test the Therm-a-Rest Parsec 0F/-18C, we took it on a three-day wild camping trip through Scotland’s Cairngorms National Park. We camped in it in temperatures down to around -9°C (the comfort limit of the bag) and when the mercury stayed above zero all night, and lugged it up and down Scottish Munros to get a real feel for what it’s like using this sleeping bag in real conditions. So how did it perform? Well, let’s start by looking at its packability.

Packability

When it comes to warm winter sleeping bags, the most problematic thing about them is often their packed size. Most quickly fill up an entire 40L pack on their own, while the smaller ones tend to sacrifice warmth to get the package down to a manageable size. 

But not with the Parsec 0F. The bag can be compressed down to something resembling an American football, which is smaller than many two-season synthetic bags that I own. What’s more, weighing a tad over a kilogram, the bag is super light for the warmth it delivers. 

So much so that I’d have no qualms about taking this bag on trips when you don’t really need the warmth, but would like the comfort. It’s so light and packable that this bag will almost certainly become my go-to for any trips outside of high-summer adventures when the temperature isn’t set to dip below 12°C. Which, here in the UK, means that the Therm-a-Rest Parsec 0F will likely become the bag I use on around 80% of backpacking trips moving forward.

Materials

The shell and liner of the Parsec 0F/-18C have been manufactured out of the same lightweight ripstop nylon material that’s comfortable on your skin and a joy to sleep in.

On the outside, Therm-a-Rest has added a handy DWR (durable water repellent) coating to help bead off any water droplets that hit the bag and to stop them from soaking into the fragile down feathers.

To provide lasting warmth in damp conditions, the down filler has also been treated with a similar hydrophobic treatment to prevent water from absorbing so quickly. Just don’t think that means you can use this in the rain: as with any down bag, the Parsec is going to lose most of its ability to keep you warm when it gets wet, so make sure you carry it in a waterproof dry bag when trekking through rainy conditions, and do your best to stop it getting wet overnight.

While we’re on the subject of down, the quality of the down filling deserves a special mention. The 800-fill power goose down is so gloriously lofty and comfortable to sleep in that you’ll never want to sleep in anything else ever again. It also lofts up quickly and doesn’t clump like in other bags. What’s more, the Parsec 0F comes with an additional quilted foot box in the bottom of the bag that provides extra warmth for your feet overnight – perfect on the coldest winter days.

Additional design features

Finally, I also really appreciate two additional design elements of the Parsec that become more enjoyable the more you use the bag. The first is the zip: it’s so smooth and easy to operate that you can do it firmly with one hand. The material rarely snags, even if you’re doing it up while lying in an awkward position, and the zipper always opens and closes with ease.

The bag also comes with sleeping pad straps on the back. And while these are small (they’re even tight when used in conjunction with one of Therm-a-Rest’s own sleeping pads), they keep your sleep system glued together, allowing you to roll around to your heart’s content in the night.

Is it worth the price?

Overall, the Therm-a-Rest Parsec 0F/-18C is, in a word, phenomenal. It’s decidedly high-end, with a performance that reflects the higher price tag. It’s packable, comfortable, lightweight and warm, and comes with a couple of additional features that truly make it stand out from the crowd, like sleeping pad straps, an additional quilted foot box, and the smoothest zip I’ve ever used.

And even though this thing is expensive, its weight and packability make it a truly versatile addition to your sleep system – suitable for camps in any weather outside of scorching summer evenings. In that sense, the Parsec 0F is, for me, a true four-season sleeping bag; one that I’ll turn to in any deep winter, spring or fall conditions, and I think the investment is worth it for those who have the money to spare.

• How Advnture tests products

Silk is one of the most popular materials for sleeping bag liners, and manufacturers make big claims about its performance. Many pitch their silk liners as a means of stopping your sleeping bag from getting dirty, while others make bold claims about their ability to boost the warmth of your bag. 

So what are they good for? Or are they just a waste of money? We take a deep dive into silk sleeping bag liners to provide some definitive answers.

Why you might want a silk sleeping bag liner?

Weight and pack size

One of the main reasons why you might opt for a silk sleeping bag liner over other materials is because of their low weight and remarkably small pack size. This is due to the weight of silk fibers and the weave of the material. Alpkit’s Mantua silk sleeping bag liner, for example, packs down to the size of a 300ml Coke can and weighs a super-impressive 108g – that’s about the same as two boiled eggs.

They help keep your sleeping bag clean

Additionally, sleeping bag liners – not just those made of silk – can act as a barrier between you and the material of your bag. This prevents sweat, oils and other potentially damaging substances from working their way into the material of your sleeping bag. Thanks to this, sleeping bag liners essentially prevent any stink from building up in your bag, thereby removing the need for you to wash it frequently – or ever. When it comes to down-filled sleeping bags, this is a huge plus, as consistent washes can damage the material and reduce their lifespan quite considerably.

This upside is one you get with any liner, though. Therefore, if your primary reason for using a sleeping bag liner is to avoid having to wash your sleeping bag so much, you could save money by looking into liners made from cotton, polycotton or polyester.

Silk is generally cozier and more breathable than other material

When compared to other materials sleeping bag liners are commonly manufactured from, silk is generally more breathable and much cozier. There’s a reason ‘sleeping in silk sheets’ has become a byword for luxury, after all. Silk is soft on the skin, doesn’t absorb odors as quickly as cotton, and works to keep you (slightly) warmer when it's cold and cooler when it's hot.

Do silk sleeping bag liners add warmth? 

For many, the main reason to use a sleeping bag liner is going to be for the extra warmth many manufacturers claim they add. Rab, for example, say that their Rectangular Silk Sleeping Bag Liner adds 2°C to a sleeping bag, which could potentially go some way into extending the depths at which you could use two-season sleeping bags or three-season sleeping bags. But how realistic are these claims? The truth is… it depends. 

Though anecdotal, online thread after online thread will tell you that silk sleeping bags don’t seem to do much in the way of increasing sleeping bag warmth for most people. And one interesting home experiment suggested that the impact silk sleeping bag liners have on warmth is very minimal, providing less additional warmth than some simple base layers would. 

When it comes to fleece and Thermolite sleeping bag liners, however, the verdict is much more definitive. Therefore, if your primary motivation for picking up a silk liner is to increase the comfort rating of your sleeping bag, you might be better served by getting a sleeping bag liner made out of a different material.

How ethical is silk as a material? 

The final point to consider when looking at silk sleeping bag liners is how they’re manufactured. Silk is an animal product, after all, created from the discarded cocoons of silkworms. To harvest the material, the cocoons are boiled whilst the larvae remain inside, thereby killing the silkworm in the process. And though the debate rages on regarding the sentience of insects, it takes up to 3,000 silkworms to create 1lb of silk – enough to make only a couple of liners.

So, are silk sleeping bag liners worth it?

When you compare a silk sleeping bag liner to one made from cotton, polyester or polycotton, it’s almost always going to be pricier. Decathlon’s and Alpkit’s silk liners, for example, cost more than twice as much as their cotton equivalents. Overall, though, silk liners are soft, cozy, light and small, and they do a great job of protecting your sleeping bag and extending its life. 

And though they don’t add much in the way of extra warmth (you’ll be warmer wearing a layer of clothes), they can make the experience of sleeping in a sleeping bag much more enjoyable. 

If those things matter to you when camping, then a silk sleeping bag may just be worth it after all.

• How to build a camping sleep system

Sleeping bag liners are pretty versatile bits of kit. They can add some extra warmth when the temperatures plummet, they can help keep things clean and they can even be used as a standalone sleeping bag on super warm evenings. But how do you make the most out of them? Let’s take a deep dive into how to use a sleeping bag liner to make sure you’re properly equipped with all the know-how you need for your next adventure. 

Different types of sleeping bag liners and their uses

If you’re looking for a sleeping bag liner, it’s first important to understand which is the best for you. With so many different styles and materials out there, let’s take a look at the benefits and drawbacks of the most popular kinds:

• Cotton sleeping bag liners are the most basic (and cheapest) types of liners out there. They provide a protective layer between you and your sleeping bag to stop it from getting dirty – but they do little more than that. Reasonably heavy and bulky for what they are, they might not be your first choice for carrying on extended backpacking trips when weight is at a premium. And as they don’t do much to increase the warmth of your bag, they’re not as versatile as other options.
  
  
• Silk sleeping bag liners are another popular style. Soft, cozy and ultra-breathable, they – like cotton liners – provide a protective layer between you and your sleeping bag, thereby preventing the bag from getting dirty so you rarely (if ever) have to wash it. Unlike cotton, however, silk is a much softer, lighter and tighter-woven material. This means that it’s substantially more comfortable to sleep in, packs down smaller and weighs much less. Decathlon’s Silk Sleeping Bag Cover, for example, is five times lighter and four times smaller than its cotton counterpart – although it does cost a little over three times the price.
  
  
• Fleece or Thermolite sleeping bag liners are ideal if you’re looking for a warm sleeping bag liner that can extend the life of your three-season bag into winter. These provide the same protection as cotton and silk liners whilst being substantially warmer. Sea to Summit’s Reactor Liner adds up to 8°C to your sleeping bag, for example, which is more than enough to turn a two-season sleeping bag into a three-season setup or make a three-season sleeping bag usable year-round. Weighing in anywhere between 250g and 700g, however, these tend to be heavier and less packable than their cotton or silk counterparts.
  
  
• Merino wool sleeping bag liners are perhaps the best choice for all-around performance. Merino wool liners protect your sleeping bag, provide a decent level of additional warmth, pack down reasonably small and don’t weigh much. They’re ideal for a variety of uses and, thanks to the antimicrobial properties of merino wool, they don’t absorb odors as quickly as many of the other materials, meaning you don’t have to wash them as often.

So, how do you use a sleeping bag liner? 

Using a sleeping bag liner is astoundingly simple: in fact, if you’ve ever used a sleeping bag, you’ve kind of already mastered it. All you need to do is roll them out inside your sleeping bag, then climb inside as you would if you weren’t using one. Alternatively, if I’m using a thick winter bag, I prefer to open the sleeping bag up fully and sit inside it before pulling the liner up to my chest then zipping up the sleeping bag to lock everything in. 

When you’ve got everything cinched tight, I find that sleeping bag liners do a great job of becoming an integral part of your sleep system. When you move, they move; and your sleeping bag follows suit too. In the summer months, however, when you use a sleeping bag liner in combination with a sleeping bag that isn’t zipped up tight, I find that you can often get tangled up inside the bag as the layers move in different directions through the night. 

Packing up sleeping bag liners

Unlike sleeping bags, many sleeping bag liners cannot simply be stuffed back into their stuff sack. Instead, they need to be rolled back up and neatly put away, much like you would with an inflatable sleeping pad. If you try and stuff a cotton sleeping bag liner back into its tiny carry sack, for example, you will almost certainly struggle to get it all in there, and you may even tear the carry bag in the process. 

Big Agnes Anthracite 20° sleeping bag: first impressions

The Big Agnes Anthracite 20° sleeping bag is a very comfortable, lofty and warm three-season sleeping bag from Colorado-born Big Agnes. Manufactured from a fully recycled shell and filled with FireLine Pro Eco recycled synthetic insulation, the bag is designed to be a reliable and environmentally friendly sack to fall asleep in after long days out on the trail.

In classic mummy style, this bag features a large hood that can be cinched down tight in cold conditions, a wide shoulder baffle to trap in heat and a large zip along the length of the bag that comes with a huge loop suitable for opening and closing when you’re wearing a pair of chunky hiking gloves.

The Big Agnes Anthracite 20° is designed to keep you warm in temperatures hovering around freezing. With a lower limit of -6°C / 22°F and an extreme rating of -23°C / -9°F, you can be confident that this bag will perform well in three-season conditions, though you may want to invest in something considerably warmer for the coldest winter nights.

When it comes to the bag’s weight, however, the Anthracite 20° comes in at a rather heavy 1.24kg. While this means the bag is absolutely not lightweight, it’s clearly comparable to other models out there that deliver similar temperature ratings, such as The North Face Cat’s Meow.

And the same applies to its compressibility: the Anthracite 20° comes with a tube-like compression sack that does a reasonable job at reducing its size, though we found that you can compress it down much smaller if you resort to using a dry bag as a vacuum pack and properly squeeze all the air out of the bag.

Big Agnes Anthracite 20° sleeping bag: in the field

To test the Big Agnes Anthracite 20°, I used it on several occasions through the end of summer 2023 and into fall. I used it on a rainy night in Bannau Brycheiniog National Park and a couple of times out on Dartmoor where I hiked around 15km before getting set up. Each time, the temperature dropped down into single digit conditions, with the night in the Brecon Beacons topping out at around 7°C. I never once felt cold in the Anthracite 20°, which shouldn’t be any major surprise considering it didn’t come close to the extremes this bag is supposed to be able to handle. 

Which, unfortunately, remains a bone of contention for me, forcing me to raise an eyebrow every time I look at the bag, especially considering the decision to attach a large label with Anthracite 20°F / -7°C written in bold across the front of it. As is the case with most sleeping bag manufacturers, Big Agnes seem to have opted for marketing over function here, as there’s simply no way I’d take this bag down to such extreme temperatures. Even their own internal benchmarks have the bag’s lower limit listed as -6℃, for example. That being said, I’d be confident in taking this thing down to freezing as long as I used it with a suitable sleeping pad – and I’m a remarkably cold sleeper.

In regards to the design of the bag, Big Agnes have included some clever features to ensure you keep warm in the places you need to keep warm most. The back of the bag comes with noticeably less insulation, for example, while the top of the bag feels about twice as thick. What’s more, the zipper is almost the full length of the bag, stopping only about 25cm above the foot box. This means you can open the bag almost into a blanket of sorts, adding an extra layer of versatility to the Anthracite 20° and helping you to keep a little cooler when camping at warmer temperatures. 

Another thing I appreciated is the oversized toggle on the zipper itself: despite being too small for thick mountaineering gloves, I found I could easily open and close the zipper while wearing a pair of thinner gloves.

When it comes to the bag’s length, I’m 5ft 10in (177cm) and found the regular size to be plenty long enough for me. The baffles captured my shoulders really well, and I could comfortably cinch everything down to trap in as much heat as possible.

• How Advnture tests products

The North Face Cat’s Meow: first impressions

The North Face Cat’s Meow is a beautiful-looking, comfortable and very well-designed three-season sleeping bag from one of the most renowned brands in the outdoor space. It comes with a comfort rating down to freezing and a lower limit of around -6°C (21°F). In full mummy style, it features an insulated hood that can be cinched tight to keep out drafts, and it comes with a vertical baffled construction to maximize packability. 

Additionally, being made from recycled synthetic materials, the bag promises to keep you warm even when it gets wet, and packs down to a reasonable size to easily stow in the bottom of your pack.

Weighing in at 1.23 kgs (2.7 lbs), the Cat’s Meow weighs pretty much what you would expect for a synthetic three-season sleeping bag. At $169 / £180 when bought directly from the North Face, it’s also at a similar price point to the best synthetic bags in the space, such as the Rab Solar Eco 3, the Mountain Equipment Nova III or the Robens Icefall Pro 900. 

And while that means that it doesn’t necessarily excel when it comes to weight, warmth and price, I think the bag is a step up when it comes to packability. Despite not being as packable as a down bag, the Cat’s Meow is constructed from vertical baffles, which allow it to compress to a comparatively smaller size than most other synthetic bags, offering an equivalent level of warmth at this price point. This means it’s easier to carry the Cat’s Meow, making it a good choice for backpacking and thru-hiking in wet conditions, especially if you pack it in a dry bag to store it, rather than in the compression sack it comes in. 

The North Face Cat’s Meow: in the field

I tested the Cat’s Meow on a few different occasions up on Dartmoor National Park. Even when the temperature approached freezing, it kept me warm and cozy, wearing just a base layer inside for maximum comfort. 

As with most sleeping bag manufacturers, however, The North Face appear to play a little fast and loose with the temperature ratings. For example, a rating of 20°F or -7°C is emblazoned in block white letters on the inside baffle of the bag. To the right, the bag’s “limit temperature” is rated as 22°F or -5°C. I’m not sure how The North Face landed on these figures, but I wouldn’t intentionally take the bag down to these temperatures without taking a space heater with me. Truthfully, I wouldn’t take this bag out in temperatures below freezing, and while I’m admittedly a very cold sleeper, I wouldn’t recommend you do so either.

In designing the bag, The North Face have made some interesting choices. The white and blue color palette is striking and results in an exceptionally good-looking sleeping bag. Also, the baffles on the hood are rigid so it maintains its shape even when you’re not in it. This means you can conveniently pop a pillow inside of it, where it’ll stay in place through the night without the need to strap it around your pad. 

Additionally, the bag comes with pre-fitted shock cords on the back of the bag, allowing you to strap yourself onto your sleeping pad to avoid slipping off during the night. These are great considerations and speak to The North Face’s famous eye for detail in its designs.

When it comes to the zip, The North Face have taken a bold design decision here. Instead of the standard floating zip stops at the foot of the zip, this is actually sewn into the body of the sleeping bag on the Cat’s Meow. That means you don’t have to faff about trying to connect the various zipper components in the dark or fumble around with tiny tags if you’re wearing gloves. 

To prevent the zip from bursting open, the Cat’s Meow comes with a strip of webbing at the foot of the zipper, which stops things from being overly extended / ripped, while a solid strip of protective material covering the full length of the zipper prevents any and all snagging. All of the zips are YKK and feel highly durable and reliable.

Regarding the size of the bag, I’m 177cm (5ft 10in) and find that the bag is long enough for me. In warmer weather, I can leave the hood open and not cinched up. In colder temperatures, I can pack myself down deeper into the bag and zip everything up tight.

• How Advnture tests products

Therm-a-Rest Hyperion: first impressions

Designed to supply warmth for less carry weight, the high-performance Therm-a-Rest Hyperion 20F/-6C is one of the lightest and best sleeping bags around.

Using high-end materials, hydrophobic treated down and with an ergonomic design, this sleeping bag can keep you comfortable in conditions down to 0°C / 32°F. There are three different unisex sizing options, to accommodate all users, and with a tiny pack size, it really doesn’t take up much room. This makes it a sought-after 3-season sleeping bag for backpackers on thru-hikes as well as alpinists in search of a warm bag for fast and light mountain missions. 

The 900 Fill Goose Hydrophobic Down (RDS) used in the Therm-a-Rest Hyperion has been Nikwax-treated to prevent moisture absorption, so the bag maintains loft 60 times longer than similar products that use untreated down. 

The sleeping bag boasts high performance credentials thanks to its box baffle construction and ergonomic design, although levels of comfort are somewhat dependent on whether you’re a side or back sleeper. The Zoned Insulation, which distributes more fill to the top rather than the foot of the sleeping bag, won’t please everyone, but the design leans more towards those looking for a performance-led sleeping bag. 

The Hyperion is compatible with SynergyLink Connectors, so it can be twinned with a Therm-a-Rest mattress for optimal efficiency and comfort, and to stop the sleeping bag from sliding around. 

From a sustainability perspective, the Therm-a-Rest Hyperion has Responsible Down Standard Certification, showing that the waterfowl in the down supply chain are treated humanely, and providing a clear link to the source. The PFC-free chemicals used in the DWR process also shows a move towards a more sustainable manufacturing process.

Therm-a-Rest Hyperion: in the field

The Therm-a-Rest Hyperion has a much more accommodating than usual range of sizing profiles, and since I’ve been on the hunt for a sleeping bag for a shorter person (myself), I was interested to try it. 

Most sleeping bag manufacturers offer men’s and women’s specific bags in regular, with an XL version (if you’re lucky). Very few seem to offer a smaller version for those who aren’t as tall. As someone who stands 166cm / 5ft 5in, I was curious put the small sleeping bag through its paces.

I tested this bag during a trip to the Dolomites in the shoulder season months. 

In the cool valley of Cortina, when the outside temperature during the day was typically around 20°C, there was massive drop at night, to 0°C and below. 

Camping comfort can be very personal – some people will sleep warm, whilst others, like me, prefer more insulation. As I sleep very cold, often requiring additional heat sources such as a hot water bottle (yes, really) even in summer conditions, my review will be focused on whether I found the Therm-a-Rest Hyperion to be comfortable as a base camp bag, rather than as a thru-hiking bag. 

Comfort

The Therm-a-Rest Hyperion uses zoned insulation, distributing the down fill strategically, theoretically where users need it most, with 70% on the top and sides and 30% on the back. 

It’s a very personal thing, but I found the design of the sleeping bag’s foot box to be cozy and warm yet too restrictive in the lower half of the design, particularly in the leg area, with a temperamental zip that doesn’t go all the way down. Therm-a-Rest say this is a design consideration to keep the sleeping bag warm with a narrower foot profile, and which also helps to decrease overall weight. As a result, it feels as though this sleeping bag is better suited to side sleepers. 

Part of the Hyperion’s design is “Synergy Link connectors”, which allow campers to move freely in their bags without exposing cold spots. The oversized draft tube ensures that heat doesn’t escape out of the top of the bag and allows the head and foot of the bag to rotate 90 degrees in either direction. It does take some getting used to, and I think for back sleepers the design isn’t as useful compared to someone who sleeps on their side.

Warmth

As someone who sleeps very cold, I need a sleeping bag to provide warmth and coziness as soon as I get in. While the Therm-a-Rest Hyperion has a comfort rating of 0°C / 32°F, and limit rating of -6°C / 20°F, I found the sleeping bag only kept me comfortably warm to around 3°C, and I would be hesitant to push it to freezing. It actually started to feel cold at 4°C while I was testing it in the Alps. 

I used a foam sleeping pad, foam roll mat and a blanket while I was camping in the valley – the air was cold enough for my breath to see in front of me – but I felt that the sleeping bag often felt cold, even though I had my base layers on, plus a long-sleeve fleece top.

As a middle-of-summer sleeping bag for fast and light alpine missions, where the choice is between not taking a sleeping bag at all, or having one that’s the weight of a down jacket – it’s ideal. For off-season valley comfort, however, a slightly warmer bag would be my preference. 

Design

For thru-hikers and alpinists, the Therm-a-Rest Hyperion is brilliant, thanks to its unrivalled packability. The super-lightweight materials and precise design means it can pack down to 15cm x 20cm in a lightweight, gray compression sack. Post-adventure, a cotton lofting sack means it can be easily stored at home to help retain its lofting properties.

The Therm-a-Rest Hyperion sleeping bag is also designed with a “Box Baffled Construction”, which uses mesh walls to maximize loft and minimize cold spots in key areas, whilst the “Comfort Fit” means it is made to be ergonomic in its shape, with a longer zipper that’s more useable than other ultralight bags. 

I noticed that the zips were quite fiddly, however, and kept catching on the outer material, which didn't have much protective fabric – a sacrifice in a bid to improve the weight-to-warmth ratio. Personally, I’d opt for a slightly more durable outer fabric.

Size

According to the Therm-a-Rest website, a size “Small” would accommodate a person up to 168cm. Rather than opting for a gender-specific fit, the Hyperion range is unisex, offering three different profiles that give width, height and girth at shoulder, hip and feet, with a lot of detail on numbers to crunch through.

With sleeping bags, a larger fit offers greater freedom to move in, but empty air can create cold spots. The Therm-a-Rest Hyperion, I found, was one of the shortest and narrowest sleeping bags I’ve ever used. This resulted in a warm setup when I got in, but the trade-off was a bit of discomfort as a result of not having enough space to spread out. There is some extra give in the torso areas, however, to allow your shoulders, elbows and hips to move more freely. 

Materials

I was impressed with the materials used. Both the shell and the lining use a premium 10D Nylon Ripstop with DWR coating. Therm-a-Rest have sourced a high-powered, high-performance, RDS-certified down.

The down used in the sleeping bag has also been treated with Nikwax Hydrophobic Down, ensuring the sleeping bag stayed dry and retained loft in cold and wet conditions, which helped provide thermal protection and an additional level of peace of mind.

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Alpkit Pipedream 400: first impressions

The Alpkit Pipedream 400 truly delivers on warmth across three seasons (and beyond, if used in conjunction with the right sleeping pad and a good tent), while remaining super lightweight and amazingly compressible. All of which makes it one of the best three-season sleeping bags for multi-day backpacking and bikepacking escapades.

As with all products made by British brand Alpkit, the Pipedream 400 has been designed, developed and tested by true outdoor enthusiasts. As a result, it has all the features most people are looking for in a sleeping bag intended for wild adventures, and it represents excellent value for money. 

Being mummy-shaped, the Alpkit Pipedream 400 is narrower at the bottom than it is at the head end, which reduces the internal size of the bag, maximizing its thermal performance (because there is less empty air for your body to heat up and keep warm). It has a comfort rating that goes down to -4.2°C, and Alpkit’s self-set limit rating extends to -6°C (the EN 13537 European standard rating for this bag actually goes right down -10.8°C). 

The horizontal box-wall baffle construction of the Pipedream prevents the down fill from clumping up, instead pinning it in place and keeping it strategically distributed around the bag, where you need it to stay warm and comfortable. This design cuts out the scourge of cold spots.

The high thermal performance of the sleeping bag is supplied by 750 fill power DownTek hydrophobic gray goose down (a by-product of the meat industry, 100% RDS-certified and audited by a third party), with a hydrophobic treatment to help preserve its lofting properties and prevent clumping if it gets wet. The 20D polyester, PFC-free outer material has a Durable Water Repellent (DWR) treatment too, and the combination of these measures mean the Alpkit Pipedream 400 can still work in damp conditions (albeit not as well as a synthetic bag, so it’s important to protect this product from exposure to water as much as possible).

The Pipedream 400 is available in a regular or a large size, and you can also opt to have the zip on the left or right side (as determined by the zip’s position when you’re lying on your back with the hood correctly positioned). Alpkit label their bags “right-hand” (which will have the zip on the left) and “left-hand’”(which will have the zip on the right) because right-handers find it easier to operate a left-located zip, and visa versa for left-handed people. There is a full-length baffle that helps stop the material getting caught in the zip.

The stuff sack has a double compression system, with two toggles, so you can squish it right down to a tiny package measuring just 19cm x 14cm (for the regular, the long version measures 21cm x 15cm when fully compressed).

The Alpkit Pipedream 400 is covered by Alpkit’s three-year Alpine Bond, and the Peak District–based brand also operate repair stations where they will fix not just their own products, but also gear made by others.

So far, so excellent – but does the Pipedream 400 perform well enough out in the wild to earn a place in our round up of the very best sleeping bags on the market at the moment? I’ve been using it in a range of conditions to find out.

Alpkit Pipedream 400: in the field

Across the last nine months I have been putting the Alpkit Pipedream 400 sleeping bag to the test in all sorts of scenarios, from a four-day fastpacking trip along the West Highland Way in the north of Scotland in late fall, through to midwinter garden sleepouts and several spring and early summer escapades in the South West of England.

Every night I have spent in this down bag has been comfortable. I haven’t felt the cold, even in the most frigid predawn hours during the winter, when temperatures were well below zero and the Pipedream was operating beyond its brief. 

Despite its impressive loft when it’s fully unfurled and in use, the Pipedream packs away into a tiny stuff sack that can be double-compressed into an incredibly small bundle. This meant I was able to use a large daypack during my four-day fastpacking trip along the West Highland Way instead of having to use a bigger bag. 

Unsurprisingly, evenings out on the trails in the Highlands of Scotland at the end of October were cold, but twinned with the Alpkit Whisper insulated three-season camping mat and the Alpkit Soloist 3-season tent, the Pipedream 400 kept me warm and comfortable.

Tipping the scales at just 865g, the amazing warmth-for-weight power the Pipedream offers has made it my go-to sleeping bag for backpacking and bikepacking adventures this year, and although I will switch to a lighter and cooler bag for mid summer trips, it won’t be packed away in the cupboard for too long before I’m reaching for it again.

On test, especially during the wee hours of the most unforgiving nights, I really appreciated the Pipedream’s excellent hood, which is easy to adjust and can be pulled in tight around your face on the coldest nights to keep any breezes at bay. The Pipedream also has a sculpted neck baffle that can be worn up under your chin if you’re feeling chilly, or cast aside if you’re warm enough – although, to be honest, this feature felt slightly superfluous to me.

Personally, I found the regular-length bag a bit short, and if you’re over 6ft / 185cm I would definitely recommend going for the long version (although the extra 20cm is quite a large increase). It would be great if Alpkit added a “short” version to the Pipedream 400 family, and made the regular 10cm longer. A women’s-specific version of the bag would be another good idea.

These minor gripes aside, however, I have been super impressed with the design, performance, packability and price of the Alpkit Pipedream 400, and highly recommend it for overnight hikers and backpackers looking for a versatile sleeping bag they can use virtually all year round.

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Somewhere deep in the recesses of your garage or attic, in an old gray camping bin that you haven’t opened in years, buried under the Christmas decorations lies a flannel sleeping bag. I haven't been creeping and sorting through your junk, I just know this to be true because everyone has one. 

Before the outdoors industry really exploded with ultralight camping gear and we got down sleeping bags built for fast-and-light missions like the Rab Neutrino Pro 400 and their slightly heavier-but-still-appropriate-for-backpacking synthetic counterparts such as the Fjällräven Abisko, we all had flannel sleeping bags.

You know the kind I mean. Yours almost definitely has an army green synthetic shell and a gray and blue flannel lining. You got it for your first summer camp with the scouts and it went on a lot of sleepovers with you during your teenage years. Come to think of it, it probably served as a cozy throw in your college dorm on movie night.

But you’ve moved on. Perhaps something sleek and ultralight like the Sea to Summit Ember II sleeping quilt has taken over for your backpacking adventures and your trusty old flannel companion has been relegated to the back of the closet. During a clear out, you might be wondering if you should just drop it off at the Salvation Army, and frankly, if you know you’re never going to use yours again, that’s exactly what you should do with it. But maybe you’re just not sure if anything that weighs more than one pound is worth anything anymore? Or perhaps you’re just planning on going on a few car camping trips this summer and your ultralight friends are trying to convince you flannel is out?

Before you go throwing your perfectly good flannel bag out with the bathwater, read on to find out exactly why fast-and-light merchants scoff at them, and why yours might be worth holding onto.

Cons of flannel sleeping bags

Let’s start with the reasons why your flannel bag might not be the best choice for your outdoor adventures. Compared to a down bag, a flannel sleeping bag is going to be significantly heavier and bulkier. A REDCAMP Cotton Flannel Sleeping Bag weighs about 4.6 lbs (2kg), for example. That’s about twice the average down bag, though it’s not too far off from a lot of synthetic bags, and in fact the Snugpak Softie Expansion 5 weighs more. So it’s probably heavier than a newer bag, but not necessarily.

However, even compared to synthetic bags, your flannel bag won’t compress down as well, and if it’s an older model it probably didn’t come with a compression sack (though you can always procure one). In general, flannel sleeping bags really aren’t appropriate for backpacking (though lord knows we managed it as teenagers) since they take up most of the main compartment of your backpack or add the equivalent of carrying a two liter bottle of soda on your back. If you’re car camping, none of this matters of course, but it means you’ve got a less versatile bag.

Then you’ve got the issue of the lining of your flannel bag being made of flannel, AKA cotton. As you might know, cotton isn’t an ideal fabric for outdoors adventures because it’s slow drying, therefore if it does get wet, it will stay wet. However, you might very well be camping in the desert or any arid type of climate where you’re not likely to see any rain and this is also a moot point. But if you’re in the UK? Stick to synthetic bags.

Pros of flannel sleeping bags

So are there any arguments for a flannel sleeping bag, or are they just less-good versions of what you can get today? It turns out that, kind of like your old Trangia stove, there are some great reasons to hold onto your flannel bag, in particular if you’re going camping in the cooler shoulder seasons.

Though for true winter camping, we’d opt for a four-season sleeping bag filled with down, flannels sleeping bags are ultra warm, so they’re great for cooler weather, and that brushed flannel is super soft and cozy compared to a slippery modern bag. They're typically rectangular bags, so you may not have a hood, but you'll have more room to move around in the night and this is great if you're a side sleeper. 

Furthermore, flannel is really breathable, so if you’re tired of waking up with a synthetic bag stuck to your skin, you might really benefit from a flannel bag that helps you regulate your body temperature.

Finally, flannel bags can be really affordable if you’re in the market for a new sleeping bag, owing to the fact that they’re not quite as technical, so if you’re just heading out on the odd camping trip and don’t want to spend the equivalent of a month’s rent, they’re a good choice.

Is your old flannel sleeping bag worth holding onto?

If you’re going to be doing some car camping in colder (but dry) weather and you already own a flannel sleeping bag, there’s really no reason to upgrade to a fancier sleeping bag, especially if yours is really cozy. For backpacking, you probably will appreciate the merits of an ultralight, packable bag, but you might find that one is too minimalist for car camping. They also make great emergency blankets to keep inside your car for winter breakdowns, and are good for camping with kids.

And if you’re just far too cool for a flannel sleeping bag? Definitely donate it and keep it out of the landfill.

Mountain Warehouse Microlite 1400: first impressions 

One of the biggest things in the Mountain Warehouse Microlite 1400’s favor is irs price. One of the biggest barriers to entry for fledgling campers is the often-prohibitively expensive price of good kit, especially kit designed for use outside of the summer months. For spring, fall and winter you need equipment that can supply real warmth, and nothing puts newcomers off going camping again like an uncomfortably cold first experience. But even the best sleeping bags – even four-season ones – don’t have to cost a fortune, as this excellent offering from Mountain Warehouse proves.

The Microlite 1400 is ideal for both cold-weather camping neophytes, and those who are more experienced but operating on a budget and in need of a new bag.

It might not be as featherlight, packable or quite as sumptuous feeling as a down-filled sleeping bag, but it is certainly light enough to be taken on backpacking adventures, and is more than capable of keeping you warm in most conditions likely to be encountered during the vast majority of the year in non-alpine terrain.

Available in versions to suit left- or right-handed people, the two-way zip can be opened from the bottom or top (to give you ventilation options) and is backed by a storm flap to keep breezes out. It boasts a good, shaped hood, which can be pulled tight around your face, and has inner pockets for keeping valuables safe, or phones warm and handy. It comes in two lengths, regular and long, and the ripstop outer fabric is robust and should last for many chilly seasons.

Mountain Warehouse Microlite 1400: in the field

I tested the Mountain Warehouse Microlite 1400 sleeping bag on a couple of campouts during the tail end of winter, when the temperatures took a late-season dip. The thermometer didn’t get down to the manufacturer’s published comfort limits for this bag, but they certainly did go south of zero and I remained toasty warm all night. I think the range is about right (see sleeping bag comfort rating explained).

But now we’re beyond the worst of winter I’ll still be keeping this sleeping bag to the front of my kit cupboard, because it’s perfectly suited to those early spring camping escapades, when days are getting warmer but nights can still be super shivery if you don’t have the right gear. Likewise, it will be ideal in the fall. In fact, I think this bag will see use almost all through the year, especially because the two-way zipper allows you to let plenty of air in and pop your feet out the end if you start overheating. You can also use the bag as a duvet, and it zips together with other bags of the same family to make a double doona if you’re camping with your nearest and dearest.

Beside the thermal performance of the Microlite 1400, which is particularly impressive for its price point, I was really blown away by all the features this bag boasts. I’m a lefty, and it’s nice to have the option of getting a bag with the zip on the right so I can locate it easily and quickly in the dark.

The hood is a good tailored shape, and once pulled in it kept all the warm air in and any chilly breezes out. There was plenty of room in the foot box, and overall it was a comfortable bag that provided me with a good night’s sleep each time I used it.

With synthetic microfill and a ripstop outer material, it’s pretty hardwearing and built to last for multiple years. Such bags are really easy to look after, you don’t need to be precious about how they’re stored or used, and they even keep you warm when they get wet. It’s a pity, though, that no recycled material has been used. And I’m not overly enthusiastic about the colors, but this latter point is a very minor grumble. All in all, I was very impressed.

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Patagonia Fitz Roy Down Sleeping Bag: first impressions 

The Patagonia Fitz Roy Down Sleeping Bag is one of the best sleeping bags on the market, with its high-quality 800 fill-power down, two temperature rating options, three length options, a jacket-like hood design, a sculpted foot box, internal chest pocket, water-resistant shell and eco-friendly features.

The Patagonia Fitz Roy comes in two versions, with different temperature ratings: the 20°F / -7°C version, which I tested, and a 30°F / -1°C version. It’s also available in three length options: short, regular and long. 

The bag is filled with 800-fill-power Advanced Global Traceable Down, which is ethically sourced and provides excellent insulation. One of the key features of this sleeping bag is its vertical baffles; this design helps to keep the down evenly distributed throughout the bag and prevents cold spots from forming.

As a pricier investment, the Patagonia Fitz Roy Down Sleeping Bag may not be ideal for those on a tight budget, weight-conscious backpackers or those looking for an ultra-compressible pack sack – you’ll need to make room in your hiking back pack for this one.

Patagonia Fitz Roy Down Sleeping Bag: in the field

To test it in the mountains during the cold season, I took the Patagonia Fitz Roy on a late winter backcountry skiing hut trip, and I was impressed with its performance. 

The sleeping bag's 800-fill-power down is very warm and has a lot of comfortable loft. I appreciate the jacket-like hood design, which allows me to cinch it tight and keep my head and neck warm, and the sculpted foot box is also a great feature, as it always keeps my feet extra toasty and allows me to move around comfortably. The bag also has a full-length, centrally positioned zipper that can be adjusted easily for temperature regulation.

I’ve also tested Patagonia Fitz Roy Down Sleeping Bag in cold summer and fall tent-camping conditions, and in every scenario it has kept me warm and comfortable throughout the night.

The water-resistant DWR shell of the sleeping bag held up well against the moisture that accumulated inside the hut overnight, and the internal chest pocket was perfect for keeping my phone and other essentials within reach.

The Patagonia Fitz Roy Down Sleeping Bag is packable and works well for trekking into the backcountry, but it is not the lightest and most compressible option. The stuff sack does help to reduce the overall size of the bag, but a more helpful compression sack with side straps would be nice.

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OEX Leviathan EV 900: first impressions 

The OEX Leviathan EV 900 is a solid four-season sleeping bag with an impressively low comfort rating for the price. Designed by OEX, which is UK outdoor retailer GO Outdoors’ own, high-end brand, the bag comes with great specs for a low price, and it can often be picked up even more cheaply during one of the numerous sales put on by the Sports Direct-owned retailer throughout the year.

The OEX Leviathan EV 900 has a sleeping bag comfort rating of -9°C (15°F) and a lower limit of -16°C (3°F). It comes stuffed with 900g (30oz) of hydrophobic 600 fill-power ethically sourced duck down, and the shell is made from 20D nylon. Featuring a thick baffle along the length of the side zip, as well as a huge baffle and lofty hood around the top of the bag, it’s built to keep you warm in colder climates – and in my experience, it does just that. 

Weighing 1.37kg (3lb), the Leviathan EV 900 is also reasonably lightweight considering the temperatures this thing is built for. And while there are bags out there that will deliver an equivalent level of warmth at a fraction of the weight, there’s simply no beating it at this price point. Moreover, the bag packs down small, especially if stuffed into a dry sack, comes with a handy internal stash pocket, and the plush inner liner is soft on your skin. At £270 (if bought at full price, £140 with a GO Outdoors membership card), I think you’ll have a hard time finding a bag that delivers a better bang for your buck (even if the color is a bit of a turn off).

OEX Leviathan EV 900: in the field

I’ve had the OEX Leviathan EV 900 for a few years now, and I’ve slept in it at varying temperatures in different climates. I’ve always been impressed by its performance, be that on a rainy thru-hike of Germany’s Black Forest National Park, dozens of winter nights in and around Snowdonia’s Glyderau, or 10 chilly October nights in Wyoming’s Grand Teton National Park. It might have lost a few of its feathers (but none of its warmth) over the years, and has a few small scuffs on the outer, but apart from that, it’s practically good as new – and I’m confident I’ll still get many seasons out of the Leviathan 900 yet.

Truthfully, my only gripe with the bag is in fact the thing that matters least when you’re deep in the backcountry: the color. It’s a sort of rotten yellow. It’s the least appealing color I’ve ever seen. This is obviously not an issue in a dark tent, though I do ask myself why the design team at OEX decided to make this the only option – especially for their flagship down bag.

I also think the testing team was a little generous with the temperature ratings. Admittedly, I’m a very cold sleeper, so I always have to shave off a degree or two when considering the temperature ratings of bags. That being said, a comfort rating of -9°C (15°F) and a lower limit -16°C (3°F) seems excessive. I’d only be confident stretching this bag down to -9°C (15°F) if I had some extra thick base layers and a warm fleece to wear inside it. There’s no way I’d get a wink of sleep otherwise.

Aside from those two things, though, the bag has outperformed all of my expectations. It lofts up quickly even after it’s been stored through the summer, and the 20D nylon outer shell has so far stopped any water from getting into the fragile feathers. Additionally, the zipper along the side of the bag is strong, thick and easy to open and shut, and when operated from inside the bag it rarely snags.

Regarding the size of the bag, I’m 177 cm (5ft 10in) and find that the bag is plenty roomy for me. When it’s warm, I can leave the top open and not cinch everything all the way up. When it’s cold, I can hunker down into the bag a little more, tighten up the baffles and zip everything up full.

As down needs to be left uncompressed during storage, the Leviathan EV 900 also comes with a handy storage sack. Wide and lofty, it lets the bag maintain its size when not in use through the summer. Additionally, it comes with an easy-to-use stuff sack that lets you compress the bag down to a smaller size for easy packing, although I tend to store it in a dry bag when I’m in the backcountry to pack it down even smaller and ensure it doesn’t get wet.

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Rab Andes Infinium 800: first impressions 

The premium Rab Andes Infinium 800 down bag lies at the top end of the four-season sleeping bag category, verging into full-on expedition use. Rab say it’s been designed for use at high altitudes and on winter expeditions, and with a sleep limit of -23°C (-10°F), it’s well equipped to deal with significantly sub-zero temperatures.

That’s based on Rab's own testing (since extreme cold weather bags do not use the EN/ISO standards), which is what the brand believes the sensible limit of the bag to be, based on past experience and feedback from their roster of elite climbers and mountaineers.

At 1.36kg, the Rab Andes Infinium 800 comes in at a competitive weight for a bag of this temperature rating. In fact, it undercuts several rival bags from down specialists like Western Mountaineering, Crux and Criterion.

The folks at Rab proudly call themselves 'masters of insulation', and with this bag, at least, they certainly deliver. It features 800FP goose down fill, which has been treated with a Nikwax hydrophobic finish for improved resistance to moisture. It lofts beautifully, trapping plenty of air within the carefully designed baffles. These use a trapezoidal box-wall construction with a differential cut to maximize loft and warmth. At the chest and foot, they’re arranged longitudinally, or top to bottom, to stop the down migrating.

The shell fabric is Gore-Tex Infinium (the new name for what used to be called Windstopper). This is a membraned fabric that is functionally waterproof, but isn’t marketed as such because it can be used in garments and equipment that don’t require taped seams. As such, it’s highly moisture resistant, counteracting the traditional Achilles heel of down sleeping bags, which is that their performance declines rapidly when damp.

Rab has also added a shiny, reflective TILT (Thermo Ionic Lining Technology) lining to the interior of the bag, which adds next to no weight but is designed to reflect radiated heat back to the body.

The bag is supplied with a cotton storage sack as well as a conventional stuff sack for use in the field. Again, it’s highly water-resistant, with a roll-top closure in addition to a drawcord. It’s just a slight shame that it isn’t fitted with compression straps to further cinch in the packed dimensions.

Rab Andes Infinium 800: in the field

The Andes series features a more tapered cut than Rab’s equally warm Expedition series, which improves warmth for weight by reducing the internal volume of the bag. The drawback of this performance-focused design is that the inner dimensions may be a little smaller than most users are accustomed to, especially at the foot box. However, we didn’t find it restrictive or uncomfortable, thanks to some clever engineering that ensures the feet are cocooned in a comfortable position. 

The hood feels similarly cozy, with drawcords that cinch in tight and are easy to operate from within. Both ends of the bag also use highly water-resistant Gore-Tex Infinium fabric inside and out to provide enhanced moisture resistance. Indeed, the whole build of the Andes 800 is much better equipped to deal with damp conditions than most down sleeping bags.

Of course, you could get similar wet-weather characteristics from a synthetic bag at a fraction of the cost, but it wouldn’t be anywhere near as light or as packable (see Down Vs Synthetic Insulation for more on this subject). Nor, in our experience, would it feel quite as luxurious or as downright cosy. In practical terms this equates quite simply to a better night’s sleep, even when temperatures drop into the minus double digits.

In short, if you need a bag this warm, we think the Rab Andes 800 Infinium offers excellent value for money. Our tester’s version is actually an older model from 2016 (when admittedly, the UK price point was £560), but it’s still going strong six years later, and we’re convinced it’ll still be with us in six years’ time.

The latest version has only got better, with the use of upgraded and even more weatherproof shell fabrics, plus that innovative reflective lining. Admittedly, the price has shot up by some £240 to £800 GBP in the UK – though it seems to be a better value purchase stateside, at $700 USD. So, although it’s a potentially pricey addition to your sleep system and one that needs to be carefully considered, in performance terms, we don’t think you’ll be disappointed.

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Snugpak Softie Expansion 5: first impressions

Snugpak’s polyester Softie insulation has been a mainstay in the British brand’s products for over thirty years. It utilizes superfine yarns bound together with special resins to mimic the properties of natural insulation such as down. The result is a really plush feeling bag that is easily warm enough for winter camping trips.

I found the Softie 5 to be a gloriously cozy cocoon to nestle within and, with a comfort limit of -15°C (5°F), it is wonderfully toasty in all but the most Baltic conditions. However, this is not a bag that’s limited to sub-zero use, as its elasticated expander panel allowed me to open things up, thus regulating the temperature inside.

However, as is to be expected with a synthetic bag, it’s not as light or a packable as its down-filled counterparts. The first thing that leaps out at you is the large pack size. Despite compression straps, it still took up a hefty chunk of my standard hiking backpack. So much so that, whenever I came to test it, I had to venture out with my 65-liter expedition pack.

Then there’s the weight, all 2.3kg (81 oz) of it. In these heady days of ultralight camping gear, it is admittedly on the heavy side, especially if you plan to wild camp. However, it’s a mere fraction of the cost of some of the leading down bags. Great value then, especially considering its luxurious feel and the amount of warmth it retains.

If you’re looking for a seriously high performing, lightweight expedition sleeping bag and you’ve got cash to spare, you may want to consider a premium down bag. However, I was happy carrying the Softie 5 around the backcountry and when you consider the excellent price, this sleeping bag is a no brainer.

Features

The Softie 5 has a few handy tricks beneath its zips. As mentioned, the Elasticated Expander Panel gave me the option of increasing its width and cooling things down a little. This adds versatility to the bag, making it a suitable choice for the shoulder seasons as well as winter. I was also able to adjust its length using the foot shorting clips, which is a good thing as I’m certainly not anywhere near its maximum user height of 6 foot 2 inches. These clips also double up as hanging clips to air the bag after use.

There’s an integrated LED light that slots into a little pocket towards the hood. This would allow me to carry on reading while my campmates were happily snoring away. Depending on how snug I needed to be, I could adjust the hood using the elasticated drawcord. There’s also an internal valuables pocket with a useful hook and loop.

The outer fabric is made from Paratex Micro nylon, which is tough yet soft to the touch, as well as being lightweight and water repellent. Should any pesky water seep into the bag, the Softie insulation retains its thermal properties when wet. The inner polyester features Reflectatherm technology, which achieves a high warmth-to-weight ratio thanks to it being coated by tiny metallic dots that help to trap heat.

Other well-thought-out features include the insulated baffle that lines the two-way side zip. Snugpak have clearly deployed every tactic to ensure minimal heat escapes in the night.

In the field

It’s clear from its sub-zero comfort rating that the Softie 5 is a very warm sleeping bag. I headed out in late fall and in the depths of winter to test it in both mild and freezing conditions. Lugging it to my high wild camps was fine but if I was to head out on a longer, multi-night adventure, I’d probably want something lighter.

I found that opening the expander panel worked really well during milder nights and at no point was I uncomfortable. In fact, once set up, I’d say I’ve never been more comfortable on a wild camp. Just a shame that it takes a little more effort to get a weighty bag like this in situ. When things got colder, the Softie continued to deliver. Even on freezing mornings I was snug and warm in the Softie’s embrace, which was no surprise as I was still well within its comfort limit.

When it came to packing down, I always made full use of the compression straps, tightening everything up to within an inch of the bag’s life before shoving it back in my backpack. Back home, I used the hanging tabs at the foot to air and dry the bag, ready for its next adventure.

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Exped Waterbloc Pro -15°: first impressions

The Exped Waterbloc Pro is a four-season winter sleeping bag designed with bivying in mind. The medium size bag (which I tested) has 800 fill down, making it very soft and warm, with a Pertex outer shell that effectively repels the weather.

Although it is sold as “waterproof” in some marketing material there is also a disclaimer that you obviously can’t lie out in a downpour and expect to stay dry. The outer shell is Pertex after all, not a crunchy waterproof jacket fabric. Not that you’d want a completely waterproof sleeping bag anyway – that’s what bivy sacks are for and a zero breathability sleeping bag sounds like a sticky night’s sleep.

That said, Exped have gone out of their way to make this sleeping bag as water resistant as possible: the entire outer shell has barely any seams, the zip has a Pertex storm flap and the 20D Pertex Quantum Pro has a 1,000mm water column. It’s designed for sleeping in open air or under a tarp – or perhaps in a hooped bivy that gets a bit damp overnight.

You can snuggle up in your down with peace of mind that – come condensation or light rain – you won’t wake up in a soggy mess of clumped down and broken dreams. The one thing they’ve avoided is any treatment of the down: “All Exped refrains from using environmentally damaging hydrophobic down treatments.”

Exped Waterbloc Pro -15°: in the field

In terms of comfort, this is a very lofty sleeping bag with lots of attention paid to keeping unwanted cold air out. There are draw cords around the hood and neckline, plus an extra down collar around the neck. Behind the zip is a similar draft excluder to prevent that annoying cold line, and the foot box has been specially engineered to stop cold spots. 

A lot of attention has gone into this: there are 11 separate chambers, individually filled with down – and you can really tell. It’s the warmest my feet have ever been in a sleeping bag. In fact, I was surprised how well it warmed up and how little air gap I had, especially considering I was testing a size bigger than I really ought to have for my height.

The one question is on the actual temperature ratings. It’s called a -15°C (5°F) sleeping bag but the comfort, limit and extreme temperatures listed on the website are different (warmer) to those printed inside the bag. And surprisingly none of those numbers are -15°C (5°F). The sleeping bag comes with a dry bag for packing and a roomy mesh bag for storage at home.

• How Advnture tests products

Sierra Designs Night Cap Sleeping Bag 20F: first impressions 

Sierra Designs has officially broken the mold with the design of this zipplerless sleeping bag. Usually you have to choose between a zip-up bag or a zip-free camping quilt, but the Night Cap offers the best of both worlds with a duvet-like design that allows you to enjoy the comforts of home and no cold, annoying zip pressing against you or letting a draft in. This synthetic bag has an oversized blanket flap that feels just like snuggling under your comforter at home and keeps you toasty at temperatures well below freezing. 

An integrated sleeping pad sleeve keeps your pad underneath you so there’s no chance of rolling off onto the cold ground and a snuggly hood lets you bundle up on cold nights. If you get too warm, just stick your feet out the self-sealing foot vent and toss the blanket flap aside. Even though this bag is very much of the mummy-shaped variety, you’ll find there’s plenty of room to sprawl out a little. With its considerable size and heft, you won’t be hauling this on a backpacking trip any time soon, but for car camping and glamping, you’ll never be cozier than in this bag. 

Sierra Designs Night Cap Sleeping Bag 20F: in the field 

I’ve been testing out camping quilts this year and tried out this sleeping bag to see if it makes a worthy replacement for a sleeping bag. While it’s not super lightweight and intended for ultralight backpacking the way a true camping quilt is, I feel like I’ve discovered a whole new world of comfort when it comes to car camping and I’m actually not sure I’m going back to a zipped bag for freezing nights when I don’t have to hike in with my gear.

Whereas your typical sleeping bag is a pocket that zips up to form something vaguely rectangular, this groundbreaking design from Sierra Designs is kind of like you’ve taking your favorite comforter from home, swaddled yourself in it the way you do on a cold night, and then stitched it up. The plush insulation, cinched hood and blanket flap make it amazingly cozy and frankly it’s plenty warm for any temperature I’d be likely to go car camping in. It’s honestly like snuggling into my own bed at night.

That said, after an hour or two I do tend to get warm, even on freezing nights, so I love the self sealing foot where I can just stick out a foot or two and instantly cool off. It has a built-in sleeve for my sleeping pad which I thought might be annoying but it’s actually great to keep from rolling off the pad in the middle of the night. I’m also a bit of a sprawler and sleep on all four sides and was pleasantly surprised to discover that I can easily curl up on one side and sleep on my back with one knee bent out to the side no problem.

This bag isn’t super light, and because it’s synthetic it honestly doesn’t compress down particularly small either. It’s the bulkiest bag I own but most of my gear is geared towards backpacking trips. I certainly wouldn’t be stuffing this into my hiking backpack as I’d have no room left over for anything else, but it’s definitely my top choice for car camping and glamping going forward, and it’s not a bad price either for such comfort.

Here’s how it performed:

Comfort

It’s one of the snuggliest, coziest sleeping bags I’ve ever wrapped myself up in, and I love having space to spread out. 

Warmth and breathability

We’ve not had too much cold weather lately, but I’ve been super toasty on nights where it gets close to zero in this bag and definitely would trust it for all car camping. There’s nothing sweaty about it, and the foot vent and blanket flap make it easy to cool off. 

Packability

This doesn’t compress down small at all – it’s more than twice the size of my sleeping pad packed down, so it’s reserved strictly for car camping. 

Durability 

So far, so good, plus there’s no zip to break. 

• How Advnture tests products

Fjällräven Abisko Two Seasons sleeping bag: first impressions

As soon as you hold the Fjällräven Abisko Two Seasons sleeping bag in your hands, a couple of things are immediately obvious: for a synthetic sleeping bag, it is both delightfully lightweight and pretty compact. But that doesn’t mean it can’t compete with the best 2-season sleeping bags. Far from it.

Once released from its stuff sack, it fluffs up nicely and offers just the right sort of thermal coverage for a summer’s night under canvas, with a great hood that can be adjusted easily.

The sleeping bag temperature rating – which is what we always strongly recommend you go by – will take you into early fall too, but this is a solidly a 2-season bag and not for winter. Armed with additional padding, which makes it a tad heavier, the women’s specific version does have a comfort temperature rating that goes down to 3°C, and the bag is also available in a long version to suit taller campers.

The Abisko is nicely designed, with a full-length two-way zip, which means you can ventilate your feet (or other body bits) if you get too hot in the night. The foot box is generous, and there’s a padded flap around the entry to keep cold drafts out.

Being synthetic, it will keep you warm even if it gets damp, and to help dry it out there are eyelets at the foot end so you can easily hang it up.

Fjällräven Abisko two-season sleeping bag: in the field

I initially trail tested this sleeping bag during a bikepacking trip in the Peak District, when storage was (obviously) pretty limited, but also the weather was unseasonably warm. It was an English summer evening, but not as we normally know it, because the temperatures barely dropped. 

I thought I was going to have to sleep sans sleeping bag at first, but the Abisko provided just the right level of comfort, and the double zip allowed me to sleep inside the bag, but with my feet ventilated, which was perfect. As the mercury did finally start to dip, it was easy to do the bag up fully and get a bit more snug, which gives me confidence that it will keep me warm on much cooler summer nights.

The hood is very easy to adjust, and while it provides a reasonably good level of cushioning by itself, the sunbaked ground was rock hard and I was happy to combine this with the Fjällräven Travel Pillow, which I was testing at the same time. The two work well together, with the pillow slotting nicely into the hood, which helps keep everything where it should be, even if you toss and turn a bit.

Although it is pretty pricey for a synthetic 2-season sleeping bag, overall I was impressed with both the performance and pack weight.

The best sleeping pads: lightweight camping mats for backpacking adventures

The best sleeping bag liners can make a huge difference to your backcountry campouts adding extra comfort, warmth and protection to the best 4-season sleeping bags.

Essentially a sleeping bag-sized sack made from a lightweight material, a sleeping bag liner might seem like a luxury you can live without, but many seasoned campers swear by them. Advantages include additional comfort and warmth – perfect to help extend your use of 2-season sleeping bags – plus they protect sleeping bags from dirt, damp and wear and tear – especially great when camping with children.

When choosing a liner, you'll need to consider your planned use. The most obvious consideration is matching it to the shape of your sleeping bag, as liners also come in rectangular or tapered 'mummy' shapes. Some brands only offer one shape, so be sure to double check before you buy.

If you're backpacking, look for a lightweight liner that packs down small and pay attention to the weight. A fleece liner will keep you extra toasty but will also be far heavier and bulkier than a cotton or silk liner.

For more on how to choose the best sleeping bag liner for your adventures, scroll to the bottom of this guide.

The quick list

Here's a brief look at what we regard to be the best sleeping bag liners available in 2026. For a deeper dive into each product, navigate to the more detailed reviews further down this guide.

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The best sleeping bag liners we recommend in 2026

The best sleeping bag liner overall

A lot of sleeping bag liner manufacturers big talk about how much insulation and warmth they can bring to your sleep system, but the Thermolite Reactor was one of few that our tester Sian found that markedly improved how much heat was trapped inside a sleeping bag.

The brand’s bestselling design is made of lightweight, synthetic Thermolite fabric, which traps in body heat fast and "all with the quite luxuriously comfy feeling of fleece against the skin," according to Sian. When coupled with a down sleeping bag, it offers a pretty much guaranteed toasty system for most climes.

Thermolite is also lighter and more packable than fleece. Due to this, you get winter-ready warmth without too much bulk and, weighing in at 248g, very little to carry too.

Need something that offers a bigger hit of heat for cold winter nights? The Reactor Extreme, is an even warmer version claiming to offer a boost of 15°C.

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The best sleeping bag liner for versatility

If you're looking for a reasonably priced liner that can amp up the warmth rating of your sleeping bag in colder months, but still works well on its own when the nights heat up, you should find the Lifeventure Cotton Sleeping Bag Liner a good choice. It comes with an inbuilt pillow sleeve, to stuff with clothes as a head rest if you're travelling light, or stop your camping pillow sliding around on your sleeping pad - one of those irritating issues we often encounter when camping wild.

It's made from 100% cotton that's been treated with Polygiene to keep odor at bay. This means you won't need to wash it as much, reducing its eco footprint. But given the environmental impact of cotton production, we'd still have liked to see organic cotton used instead. It might not be the lightest liner we've featured here, but it packs down well and will easily fit into a large daypack. The Lifeventure liner comes with its own ripstop stuff sack, that rolls and clips shut like a dry bag, and the loop handle means you can hang it off the ground when you're not using it. Make sure you do keep it dry when you're using it, as cotton loses all its thermal properties when damp - the stuff sack doesn't claim to be waterproof, but should help with this at least a bit.

Read our full Lifeventure Cotton Sleeping Bag Liner review

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The best sleeping bag liner for warmth

"Heavy but pleasingly soft and warm, the Snugpak Fleece Liner is ideal for bitter winter nights," says our camping expert Sian. If warmth and comfort is top of your sleeping bag liner shopping list, try Snugpak’s luxuriously soft offering for size.

This fleece liner is deliciously cosy to climb into after a long day’s hiking, traps in body heat quickly and is still breathable if you do get hot in the night. Reviwer Sian also loved the full-length zip for easy access – a far cry from some of the liners she tested, which she had to really wiggle about to clamber into.

A warm liner usually equals a weighty liner and this is no exception, weighing in at 1kg. Put into context, this design weighs more than twice some lightweight sleeping bags. However, if intend to you camp throughout the year and fancy giving winter glamping a go or want to add warmth to your chilly camper van, this fleece liner is well worth it.

Our reviewer Sian also sees the potential of this liner as a standalone piece, saying: "I found the reassuringly thick and soft fleece also made this a nice standalone sleeping bag for chillier summer nights when you still want a bit of weight over you."

Read our full Snugpak Fleece Liner review

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The best sleeping bag liner for water-resistance

If you're looking for something to shield your premium bag, kepping it in tip top conditions, this may well be the answer. Snugpak’s Paratex liner is all about protection. It’s designed to wick moisture away from the body, thus keeping you dry without affecting your precious bag’s lining. As is often the case with sleeping bag liners, it's straightforward to launder too.

Sian, our expert teser, found this liner also worked well as a standalone lightweight sleeping bag, too. This is because the outer material is water-resistant and windproof, making it ideal for balmy summer nights bivvying or spent in a hammock. In these cases, you won't require much warmth but some protection in case the weather turns while you’re asleep is obviously valuable.

Sian admitted that she "tended to slip and slide a bit in this silky-feeling liner." She recommended that "if this bothers you, pick a fleece or cotton liner instead. "

Read our full Snugpak Paratex Liner review

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The best sleeping bag liner for eco-credentials

This bright liner (our reviewer Sian tested the orange version) is a solid choice for cooler camping conditions in spring and fall, or for use as an additional layer during winter stays in hostels or mountain huts. Its polyester material traps in warmth nicely, making it ideal for such scenarios.

However, in hot or humid conditions, the polyester isn’t breathable enough to be comfortable. A cotton or silk liner does the job better for these kind of adventures. According to Sian, the "liner also does a great job of protecting your bag from dirt and sweat, and once you’re back home, it comes out of the washing machine as good as new, and dries fast."

The majority of the liners Sian tested weren't made from recycled materials. However, the Slumra features 100 per cent recycled polyester, making it a more sustainable choice than most. It's also a decent option for backpacking trips and hut-to-hut hikes, thanks to its low, 340g weight.

Read our full Fjern Slumra Liner review

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The best sleeping bag liner for value

"The cheap and cheerful Decathlon Polyester Liner packs easily into any rucksack and offers good protection for your sleeping bag," says Sian, our expert tester. It's perfect for casual camping, school or scout adventures, or if you were looking to try out a sleeping bag liner without making a larger investment.

Its a simple liner that fits well into rectangular sleeping bags and offers good protection. As ever, it's also super easy to removed and launder. It also adds a fair degree of insulations, making it a solid option for spring and fall nights. However, the downside is that polyester isn’t particularly breathable, so it'd be easy to overheat on hot nights.

It weighs in at a respectably light 260g and packs down small enough to fit nicely into a daypack. Sian enjoyed using it for hut to hut hiking and shorter wild camping weekends in cooler weather where her priority was keeping her sleeping bag clean and in good condition. She reckons it's hard to argue with Decathlon's assertion that this represents great value.

Read our full Decathlon Polyester Liner review

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The best sleeping bag liner for festivals

Summer, camping and the backcountry go together like mac 'n' cheese – this is, until you overheat in your stuffy three-season sleeping bag. On warmer nights under canvas, this lightweight and breathable liner is a good option.

It's made from Polycotton, a mix of cotton and polyester. In this case, it's 35 per cent cotton, 65 per cent polyester, offering a good balance between the softness and moisture-wicking properties of cotton and the added durability of polyester.

"This simple but quite thin-feeling rectangular bag is a good choice for tropical travelling, festivals and more casual summer camps," says Sian, our expert tester. It also launders easily and dries quickly when back home.

A sewn-in pillow pocket is great for keeping a camping pillow in place all night if you're the kind of person who tosses and turns in your sleeping bag. The design is a little bit snug to slide into, so taller or bigger campers may want to choose a liner with a more generous width.

Read our full Mountain Warehouse sleeping bag liner review

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The best sleeping bag liners comparison table

How we test the best sleeping bag liners

Our expert reviewers test all sleeping bag liners by heading out into the hills and moors in all kinds of conditions, setting up camp and spending several nights in them. We have paired each of the bags featured here with an appropriate sleeping bag (i.e. one with a temperature rating that suits the season and temperature at the time, or one which is slightly less warm than the conditions call for if used without a liner) and then assessed the product performance.

Specific features (including weight, size, comfort, packability and thermal performance) are tested against claims made by the brand, and we assess factors such as durability, environmental impact and value for money

For more details, see how Advnture tests products.

What is the point of a sleeping bag liner?

You may be wondering whether sleeping bag liners are worth it. There are several advantages to having a sleeping bag liner and very few disadvantages. Lets get the latter out of the way, as it's pretty quick. The main cons are that it's one more thing to pack and you have to invest in one. However, some are so lightweight and packable that you'll barely notice it and we'd also argue that in the long run, it's an investment that will pay itself back – just read our first point below.

So, let's get into the pros:

1) A sleeping bag liner provides a protective shield around the inside of your sleeping bag. A sleeping bag can be a very expensive purchase, yet the very nature of camping or backpacking means we often end up getting in these precious cocoons while being more than just a little grimey. You simply don't want all that dirt, sweat, body oil, sun cream and the rest on your pricey sleeping bag. An affordable liner will add years and years to the lifespans of your prized sleeping bags.

2) A sleeping bag liner is easy to launder. Unlike a sleeping bag, which is a faff to clean at the best of times, not to mention the fact that the process reduces the performance of its insulated fill, sleeping bag liners are usually machine washable.

3) A sleeping bag liner provides additional warmth. This is particularly pertinent for you winter campers, as you need all the help you can get to stay toasty! It's worth noting that fleece liners add more warmth than silk ones.

4) A sleeping bag liner tends to be more comfortable against the skin than a sleeping bag's inner fabric. For maximum comfort on your camping trips, a liner is a no brainer.

5) A sleeping bag liner is a standalone option in warm weather. Yes, it's not just additional warmth in winter that the best sleeping bag liners are good for, they're also great for balmy summer nights. Rather than having to haul your bulkier sleeping bag around, you can simply bring you lightweight and ultra-packable liner.

How to choose the best sleeping bag liners

Not all sleeping bag liners are created equally. You’ll find plenty of different materials and shapes on the market, but our handy guide and frequently asked questions below will help you pinpoint the best sleeping bag liner for you. Whichever design you choose, liners tend to be compact and affordable (our recommended liners start from just $13 / £8), so we reckon they’re a bit of a must for camping adventures – but consider the following factors…

Packed size

Have a think about where and how you plan to use your new sleeping bag liner before you invest in a shiny new one.

First up, pack size: if you’re going wild camping or usually only camp for a weekend at a time, small, lightweight models that pack into a backpack or a bike pannier are your best bet. If your idea of a good camping holiday is full bells and whistles in a campsite or a glamping tent, you can pick a heavier, warmer but bulkier liner. Likewise, if you want a warm fleece liner for winter, you may need to pick a liner with a larger pack size but which offers that much-needed added heat.

Weight

Second, weight: some silk liners weigh a smidge above 100g, so they’re ideal for weight-watching fastpackers. Thick fleece liners can weigh 1kg – more than some sleeping bags – so they’re better for car campers and winter weekend camps.

Make a decision on what weight suits your setup before you shop – or you could even invest in a few different liners.

Breathability

The breathability of your liner will depend on the material it's made from. Silk is lightweight and wonderfully breathable, while polyester is cheaper but not quite as strong in the breathability stakes. For those looking for warmth and breathability, fleece is a good option, though it's obviously not as smooth on the skin as silk. Decisions, decisions. For more on the materials that sleeping bag liners are made from, scroll further down.

Heat rating

Just as sleeping bags have temperature ratings, so to do sleeping bag liners. Every liner is different and it's worth paying attention to the product packaging and reviews for this. A good liner can add anything from 5°F to 25°F of warmth to your sleeping system.

Anecdotally, silk sleeping bag liners don't add much warmth to a sleep system, whereas users tend to really notice the difference with fleece and Thermolite liners. So, if adding warmth is

FAQs about sleeping bag liners

What materials are sleeping bag liners made from?

You’ll find liners on the market made from all kinds of material. The priciest is silk, which is brilliant for camping as it’s lightweight and feels great against the skin. Silk also offers the best protection from mosquitoes and other biting nasties too, so it’s a good choice for nights in hot tropical countries.

Cotton and polycotton are ideal for summer weather, as they are highly breathable, and brushed cotton also feels rather like your favorite duvet would, so it’s nice if you’re sick of the feel of your plasticky sleeping bag – but remember: cotton offers no thermal protection if it gets wet and can be dangerous in alpine scenarios as a result.

Polyester is affordable and does trap in warmth, but doesn’t breathe well at all, so it’s best used in spring and fall rather than hot or humid conditions.

Winter campers should pick a warm fleece liner – it’s often the bulkiest material on offer but traps in warmth quickly while still being breathable, soft and quick to dry if you pop it in the wash.

What is the best shape for a sleeping bag liner?

Liners come in rectangular or tapered ‘mummy’ shapes, just like sleeping bags. Mummy shapes offer less range of movement but are usually warmer, while rectangular bags and liners offer more room to toss and turn but tend to trap in less heat. Shopping for the right-sized sleeping bag liner is easy: just pick a liner that matches the shape of your favorite sleeping bag.

How do I clean a sleeping bag liner?

Cleaning a sleeping bag liner is very easy indeed. In fact, it's one of the main benefits of having a liner, as it's much more straightforward to launder and dry than a sleeping bag.

Sleeping bag liners can be laundered at home using a standard washing machine and detergent. In terms of settings, use a gentle or delicate wash cycle to avoid damaging the liner and, as with most technical outdoor gear, don't use fabric conditioner, as it will have an adverse effect on its moisture wicking properties.

Similarly, avoid using a tumble drier, as this will also compromise the fabric's performance. Simply hang the liner out to air dry.

Sleeping bag alternatives? That can’t possibly be a thing, can it? No matter what type of camping you’re doing, the almighty sleeping bag seems like the one absolutely essential piece of kit that you simply cannot go without. You might be able to build a natural shelter using tree branches and a tarp or make a mattress out of a pile of leaves but surely you need a sleeping bag? After all, it provides crucial insulation against the cold and a little welcome cushioning in an activity that’s not exactly known for its exceptional comfort.

Despite its clear importance in the world of sleeping outdoors, there are actually times when you might want to sacrifice the convenience of a traditional sleeping bag for something that better suits your needs, for example:

• Camping in hot weather when a sleeping bag may be too warm.
• Thru-hiking or ultralight backpacking where you’re trying to cut down on weight and bulk in your backpack.
• If you’re a side sleeper or just find that you need to sprawl out more than a zipped bag allows.
• Camping on a budget – a good sleeping bag usually comes with a hefty price tag and you might not be looking to splurge.

What can I use instead of a sleeping bag?

If your sleeping bag just isn’t working for you, you might want to do a little research on the different types of sleeping bag to find out if there’s a shape that’s better for your sleeping style. If you’re an avid camper, you also might need to invest in a couple of different sleeping bags to account for different seasons and temperatures – for example, your 3 -season sleeping bag might be brilliant in the colder off season months, but too warm for summer, so perhaps you need a 2-season bag. 

It’s also possible that you might just need a different approach altogether. If that sounds like you, check out these five sleeping bag alternatives:

1. Camping quilt

For ultralight camping where you still want the good insulating properties of a down or synthetic sleeping bag but can afford to lose a little warmth, a camping quilt is easily your best choice. A camping quilt is essentially half of a sleeping bag, made using the materials and construction but without the zipper and the layer that goes underneath you. More than just a blanket, however, a camping quilt has a foot box to keep your toes warm and straps that go around your sleeping pad to cocoon you and keep it in place. Since your sleeping pad provides insulation and protection against the cold ground, you’ll find this provides ample protection even in fairly cold temperatures and gives you a bit more freedom in your sleeping positions too. However, good camping quilts are priced right up there with good sleeping bags, so don’t necessarily expect to save money with this option.

2. Camping blanket

Next up, if it’s going to be mild or warm overnight, or if you’re car camping, you could go old school and use a camping blanket. They might be low tech, but they’re what campers and soldiers used before the advent of the sleeping bag and they’re a viable option. Camping blankets are simple blankets that come in a range of fabrics, some of which pack down relatively small. Our list of the best camping blankets includes super cozy and comfy fleece and quilted options, while wool blankets will offer the most insulating power on chilly nights, even if they get damp. Blankets can be bulkier and heavier than high tech sleeping bags, and for cold weather you’ll want more than one, but they are generally really affordable and they’re also versatile and can be used as a shawl, picnic blanket or rolled up into a camping pillow.

3. Sleeping bag liner

You might think of a sleeping bag liner as something that you use for cleanliness rather than an actual alternative to a sleeping bag, but in fact, under the right conditions it can make a worthy contender in the arena of sleep systems. While the lighter models on our list of the best sleeping bag liners will only do on warm nights, there are fleece options which will provide some warmth on cool nights and some are amazingly light and packable compared to a sleeping bag. They’re also significantly cheaper than a sleeping bag and can add insulation to your bag in the winter. On the down side, a sleeping bag liner doesn’t provide any cushioning so you may want a thicker pad beneath you, or use an air mattress or a camping cot.

4. Extra clothing

If you’re already bringing extra clothing for hanging out after the sun goes down, you might have enough insulating power to leave your sleeping bag at home. Wrapping up in a down jacket over a long sleeved wool base layer and wearing thermal underwear underneath your insulated trousers, combined with a hat, your best hiking gloves and good wool socks might provide ample warmth if it’s not too cold out. This option definitely isn’t as cozy as being wrapped up in something, but it’s cheap and low maintenance. Of course, if you end up just packing loads of extra clothes, you might be better off carrying an actual blanket or bag.

5. Comforter

Finally, if you’re car camping, why not just bring your comforter from home? In fact, go wild and pack your pillow too. There’s nothing to say you can’t prioritize comfort when you’re car camping, and having expensive gear doesn’t add much when you’re driving right up to your campsite anyway. If it’s chilly, your winter comforter will provide good warmth while a larger one can be wrapped around you, and this is definitely a cozy option. Of course, it’s too bulky and heavy for backpacking, and camping gear does have a tendency to get dirty, so consider buying a cover for it that’s only for camping, or be prepared to have some laundry to do when you get home.

A word of warning

Most of these options aren’t as good as a classic sleeping bag for very cold temperatures, and if you’re unsure of the conditions where you’re heading, you're camping at high altitude, or you’re new to camping, we do recommend you carry a back up emergency blanket – this won’t serve as a replacement for a sleeping bag, but can help prevent hypothermia in a pinch.

• 10 sleeping pad alternatives for car camping and backpacking

Therm-A-Rest Space Cowboy 45F/7C Sleeping Bag: first impressions

Therm-A-Rest tout this sleeping bag as providing worry-free warmth, and at least for summer camping when rain or morning dew are an issue, that’s true. With a comfort rating of 52F/11C and a limit rating of 45F/7C, it does provide ample warmth for summer camping and it’s made from the same soft fabric we’ve come to expect from Therm-A-Rest. Because this bag is made using synthetic down, it has two major advantages: first, it’s quick drying and continues to insulate when wet, so there’s no need to worry about damp mornings, and second, it’s considerably cheaper than down alternatives in the same range.

Now, synthetic bags don’t pack down as much as down, but this one comes in a storage sack that doubles as a stuff sack, and it’s certainly possible to take this backpacking, but the lack of compression straps mean it’s a little bulky, while the packed size is certainly no issue for car camping. The dual-purpose sack also means less materials are used in the production of this bag, which combined with the use of recycled materials makes for a kinder carbon footprint. A nice touch is the addition of two straps that connect to your sleeping pad to keep you from rolling off in the night, improving warmth and comfort. Anti-snag zippers help to improve the durability of this robust bag, and while we wondered if the foot box couldn’t be a little roomier, we think it’s great value for money if you’re seeking a good quality summer bag.

Therm-A-Rest Space Cowboy 45F/7C Sleeping Bag: in the field

I’m still relatively new to synthetic sleeping bags, but they’ve certainly come a long way since the 1980s and I’m beginning to view them as a serious contender for camping, thanks to good quality bags like the Space Cowboy.

This sleeping bag is definitely designed for summer camping and this summer, we’ve had a lot of wet weather, so I’ve been quite happy to get to fend off the elements in a synthetic bag. This bag has a DWR finish that keeps dampness at bay, dries super quickly and most importantly of all, stays warm when wet so I haven’t spent the cool, damp mornings shivering away.

It’s not exactly packed with features, but one detail I really like are the two straps that connect it to my sleeping bag so that I don’t roll of it in the night and wake up cold and uncomfortable. In terms of the fabric and coziness, I generally find Therma-A-Rest’s sleeping bags to feel extra soft and this one is no exception. That said, I can’t help but think the foot box is just a tad too narrow for comfort, and I’ve noticed this before with their other bags. Of course, that means my feet stay toasty all night, but I feel I could benefit from an extra inch or two.

It comes with a storage sack that has two draw cords and doubles as a stuff sack. I like that this means less materials are used, plus the storage sack compresses it a little, which means it doesn’t take up so much room in my closet. It certainly doesn’t pack down as small as my down bag, and I can’t get it down as small as the advertised 10in x 8in but it still gets respectably small – compression straps would help.

It’s not the most breathable bag I’ve ever tried out, though it’s sometimes hard to tell with Scottish humidity, but fortunately in the summer I usually unzip my bag anyway. It’s a good quality bag and not nearly as fragile as my down bags, and despite its simple design I think it’s great value for money if you’re looking for a summer-only bag.

Here’s how it performed:

Comfort

Cozy and soft fabric, but the foot box might be a little snug for some.

Warmth

Plenty warm for summer camping, but not suitable for cold nights. 

Weather resistance 

Good DWR coating repels moisture and if it gets soaked, it’s fast drying and stays warm.

Packability 

Doesn’t pack down as small as advertised, though you could use an existing compression sack with straps to help with that.

Breathability

Not the most breathable sleeping bag out there, you might need to unzip and kick a leg out.

Durability 

Anti-snag zipper, sturdy fabric and no leaking feathers ensure this will hold up against sharp sticks and rough adventures.

• Best sleeping pads: from portable pads to luxury airbeds

Rab Solar Eco 3 sleeping bag: first impressions 

Rab’s newly launched Solar collection is its first line of synthetic sleeping bags and the Solar Eco 3 is less than half the price of many of its down sleeping bags. The company known as one of the best in the business doesn’t disappoint with this luxurious-feeling bag, and best of all, it’s environmentally-friendly too.

The Solar Eco 3 is a plush, warm 3-season sleeping bag packed with synthetic down that continues to insulate when wet, dries quickly and is designed to withstand temperatures as cold as -8F/-20C. This mummy-shaped bag with adjustable hood packs in more down on top, where you need it, with a dual-layer concertina blanket construction that traps loft and warmth. The outer is treated with DWR to repel morning dew, rain-soaked tent walls, and accidental spills in your backpack. 

Made entirely using recycled materials, this sleeping bag has a lower impact on the planet, but still manages to be high performing on freezing camping expeditions. A hidden zip pocket near the collar lets you stash any gear you want close by while you sleep, and there’s enough room inside to sleep in many positions. This robust bag is definitely a little heavier and less packable than your typical backpacking bag, and is too warm for summer camping, but for cold car camping and expeditions where you’re hiking out from base camp each day you’ll be thrilled with the quality, level of comfort and warmth provided, especially given the price.

Rab Solar Eco 3 sleeping bag: in the field 

This is my first synthetic sleeping bag (excluding cheap car camping bags I used as a kid) and it’s also my first bag that’s not ultralight and packable. For years I’ve been using my lightweight backpacking bag or camping quilt even when car camping, so the bulk and heft of this bag took me by surprise. However, what comes with all that extra down is unbelievable cushiness and comfort. This bag is so robust that at first I thought perhaps it had a built-in sleeping pad but in fact, it’s just really plush. I got to use it on a few car camping trips before things warmed up this year, and I can’t believe how toasty it is. 

The mummy shape design is definitely cozy and though I wouldn't want to foot box any narrower, there's enough room that I can sleep with one leg bent out to the side, but not both knees bent, so you might want to order the wider size if you like to sprawl out a bit. The adjustable hood and collar works a charm and one unusual detail I love is a little zip pocket in the collar where I can stash things I like close by, such as my best headlamp, watch and earplugs – this would definitely come in handy if you’re tarp camping or building a shelter and don’t have tent pockets for gear, although you may find it annoying to have the zip close to your face. I didn't notice the zip while I was sleeping, personally. Another nice perk is that you can order this with either a right or left side zip, which I know will be game changing for some campers.

Synthetic down doesn’t pack down as small as real down, so this takes up quite a bit of room in my backpack and I've saved it for car camping, but it also doesn’t leak feathers everywhere, which makes a nice change for me. I pulled it out of my tent to take a good picture of it and it got rained on so I actually got to test out the DWR – the water beaded on it nicely and I stuffed it away damp and it was dry when I pulled it out later, which is a huge bonus when camping in Scotland. Plus, synthetic down continues to insulate when wet.

Rab is a major player in sustainability and this bag is made entirely using recycled materials, which is a major plus for me, and the quality of this sleeping bag is extremely high end. Finally, Rab makes some of the absolute best sleeping bags on the market and this is the first I’ve seen from them that comes in at a pretty affordable price. I’d take this anywhere I’m going to be camping in cold temperatures and not going to be walking too far.

Here’s how it performed:

Comfort

This is the coziest, plushest sleeping bag I’ve ever slept in. The synthetic down has a nice, firm feeling to it and the out is really soft. 

Warmth

This holds up against freezing temperatures (and lower) no problem, especially with the adjustable hood and collar. 

Weather resistance 

DWR coating repels moisture from the walls of your tent, and synthetic down continues to insulate when wet. 

Packability 

Doesn’t pack down as small as down sleeping bags and I’d have a hard time fitting it in my pack along with everything else for a backpacking trip, but it will easily fit in the trunk of your car or in a duffel or travel bag if you’re hiking out from base camp each day. 

Durability 

Super robust and great quality, especially compared to other backpacking sleeping bags, which tend to be flimsy. 

• Best sleeping pads: from portable pads to luxury airbeds

If you’ve been building out your camping kit and are learning all about gear maintenance to prolong the shelf life of all your best equipment, you’ve probably heard the term sleeping bag loft and perhaps have some idea that it’s important to keeping you warm at night. But what actually is loft in a sleeping bag? Do sleeping bags lose their loft, and if so, do they stop keeping you warm? And can you restore loft in in your sleeping bag? We’ll answer all of these questions in this article so you can make sure your best sleeping bag keeps performing for you night after night, whether you’re car camping or backpacking. 

What is loft in a sleeping bag? 

Loft is a term that refers to the volume taken up by the down in your sleeping bag (or down jacket, for that matter) and it’s also known as fill power. It’s a way to measure the fluffiness of your sleeping bag and it matters because the more loft your sleeping bag has, the more air it traps. Since down insulates by trapping air, the more air it can trap, the better it is at keeping you warm. 

Do down sleeping bags lose their loft? 

If you’ve ever had a down pillow, you’re probably familiar with the journey from a plump, supportive place to rest your head at night to a rather sad, deflated looking rectangle after a few years of nightly use. Though slowly leaking feathers has something to do with this, the primary culprit of down pillows losing their loft over time is simply that you’re lying on them, and the weight of your head compresses them so they trap less air. 

In a sleeping bag, not only are you lying on it at night but during the day it might be tightly packed inside your backpack for hours at a time, causing it to lose loft. The result, of course, is that you end up with a sleeping bag that’s not trapping as much air as when you first bought it, and you’re not as warm at night. 

Can you restore loft to a sleeping bag? 

First, how do you know if your sleeping bag has lost its loft? Basically, there are three tell tale signs:

1. It doesn’t look as fluffy as when you bought it.
2. It doesn’t keep you as warm at night as it used to.
3. When you hold it up against the light, you can see the light shining through.

If you’ve run this check and you’re pretty sure your sleeping bag has lost some of its loft, you don’t necessarily need to go and buy a new one. Start with these simple procedures and see if you can breathe some life back into your bag:

• Don’t store your sleeping bag in its stuff sack – save that for when you’re on the trail and when you get home, place it inside its larger, non-compressing storage bag.
• Shake your bag out and lay it out flat for a couple of hours.
• Fluff the down with your hands.
• Put your sleeping bag in the dryer with no heat and a couple of tennis balls.
• Wash your sleeping bag on cold with no detergent according to the instructions on the label, then dry it in the dryer with the tennis balls (it may take several cycles).
• Send your sleeping bag in to the manufacturer or a gear shop to refresh it for you.

Mountain Warehouse sleeping bag liner: first impressions

You can’t call the Mountain Warehouse sleeping bag liner a liner for all seasons, but for the season it specializes in, it’s a winner, which is why it nabs a place in our best sleeping bag liner buying guide.

Summer is a lovely time to camp outdoors – until you overheat in your stuffy three-season sleeping bag. On hot nights under canvas, swap to this lightweight and breathable liner. 

This simple but quite thin-feeling rectangular liner is a good choice for tropical travelling, bothying escapades, festivals and more casual summer camps.

Mountain Warehouse sleeping bag liner: in the field

Polycotton is a mix of cotton and polyester (here, it’s 35% cotton, 65% polyester), which offers a good balance between the softness and moisture-wicking properties of cotton and the added durability of polyester. 

We found this cotton mix felt really nice against the skin, unlike some slippery polyester liners – if you miss the softness of your favorite duvet when you’re camping, this liner might help you get a comfier night’s sleep. 

It washes and dries easily when you’re back home from your adventures (although the pale blue color does show the dirt easily). A sewn-in pillow pocket is great for keeping a camping pillow in place all night if you tend to toss and turn in your sleeping bag. 

Mountain Warehouse’s design is quite snug to slide into, so taller or bigger campers may want to pick a liner with a more generous width. Shorter men, women and teenaged campers should find it fits them fine, but there isn’t loads of room to move about.

Sleeping bags have become such a ubiquitous piece of camping kit, nobody even questions whether you need one anymore when it comes time to sleep outdoors. You just pack it in its stuff sack and load it up without thinking about. But you may have noticed that it’s one of the priciest pieces of camping kit you own, it’s bound to be the bulkiest item in your backpack and you don’t always get the best night’s sleep in it. So can you ditch your best sleeping bag and take a simple camping blanket instead? In this article, we measure the pros and cons of the classic sleeping bag vs blanket to help you find a more comfortable, budget-friendly and lightweight approach to sleeping wild. 

Sleeping bag vs blanket: warmth 

It probably goes without saying that a sleeping bag designed for 20°F/ -6°C temperatures will provide more insulation than probably any blanket, so for cold nights it’s the smart choice, but for milder temperatures and summer camping, a good sleeping pad beneath you and a blanket on top will provide all the warmth you need.  Of course, with a blanket there will always be a bit of a draft whereas sleeping bags do a great job of sealing all the heat in, but it all comes down to what kind of overnight lows you’re expecting.

Another consideration here is moisture – most really good sleeping bags are made using down which doesn’t insulate when wet, so if you’re going into challenging, damp conditions, a wool blanket is the top contender.

Sleeping bag vs blanket: comfort 

Comfort is probably the most subjective criteria in this list, but it’s also one of the most important considerations you’re likely to make when building a sleep system for camping. If a sleeping bag keeps you warm on a cold night, that definitely goes a long way towards your personal comfort, however most of us don’t find being zipped up in a bag especially comfortable, particularly if you’re a side sleeper. A blanket allows you to position yourself just as you would in your bed at home, which might sound like music to your ears. 

Sleeping bag vs blanket: packability 

Though sleeping bags can be increasingly packable and lightweight, especially if they’re intended for backpacking, blankets contain less material and no zip, so they’re often lighter and pack down smaller. That said, a sleeping bag always comes with a stuff sack which might even have handy straps for attaching it to your backpack, whereas a blanket often won’t, but you can still wrap it in plastic and pack it or attach it to your pack using bungee cords. 

Sleeping bag vs blanket: versatility 

A sleeping bag really only has one function, and that is to sleep in. A blanket, meanwhile, can go under or on top of you, be used in a hammock and fold up and act as a camping pillow. Beyond sleeping, you can use it for picnics and temporary shelter too. 

Sleeping bag vs blanket: durability 

Durability always depends on materials and construction, but generally speaking, your sleeping bag will be one of the most fragile items in your camping kit. The fabric tears easily and of course, zips can break or become stuck, especially if you’re not careful. A blanket is generally much sturdier with  no zip to break on you and as long as it's made with a non-flammable material you can wrap it around yourself when you're gathered around the campfire and don't have to worry about stray sparks.

Sleeping bag vs blanket: cost 

Finally, a good sleeping bag can cost you well up into the hundreds of dollars, whereas you can pick up a good blanket for under $50, so if you are on a budget, a blanket is the clear winner. 

Sleeping bag vs blanket: the verdict  

If you’re seeking an alternative to a sleeping bag, no matter your reasons, it certainly looks like you could do a lot worse than a camping blanket. Though you’ll probably want to stick with your sleeping bag for cold nights, a blanket can help you get a better night’s sleep in the warmer months at a fraction of the cost, and since it has so many other uses (even when you’re not camping) we can’t see any reason not get yourself a camping blanket. If you’re still not convinced, however, check out our comparison of camping quilts vs sleeping bags to see if there’s a better option for you.

Snugpak Fleece Liner: first impressions

The thick and toasty Snugpak Fleece Liner is all about staying cosy and warm no matter what the outside temperature is doing, which makes it a winner if you don’t have an expensive cold-weather sleeping bag but fancy some winter glamping or cold-weather camper vanning.

While this is a warm liner, though, you do have to compromise on weight: at 1kg, this design is more than twice the weight of some of the lightweight sleeping bag liners I tested for our best sleeping bag liner buying guide. And it’s bulkier too, so it’s not ideal for backpacking. 

Snugpak Fleece Liner: in the field

If warmth and comfort are high on your list of sleeping bag liner priorities, Snugpak’s luxuriously soft offering is a surefire winner. 

This fleece liner is deliciously cosy to climb into after a long day’s hiking, or a chilly afternoon on the water. I found that it traps in body heat nice and quickly, and yet it is still breathable if you do get hot in the night. 

I also love the full-length zip for easy access (unlike some liners I tested, which I had to really wiggle about to clamber into).

On test I found the reassuringly thick and soft fleece also made this a nice standalone sleeping bag for chillier summer nights when you still want a bit of weight over you. Some barely-there summer liners feel too thin on their own, but this design is just like wrapping up in a fleece blanket. You may even find yourself reaching for it while lounging on the sofa at home. In fact, this liner doubles up as a fleece throw or as a casual blanket around camp. 

I also found that the olive color didn’t show dirt up easily. It’s just a pity the fleece isn’t made from recycled plastic. 

Rab Ascent Silk Liner: first impressions

The Rab Ascent Silk Liner tips the scales at just 130g/4.6oz, so it will suit even the most weight-wary backpacker, as well as working for travelling and traditional camping adventures. 

A natural substance, silk is a bit of a wonder material for liners, as it traps in heat quickly but still breathes well and has a great warmth-to-weight ratio. It feels pleasingly soft against the skin and even has antimicrobial properties, so it’ll help keep your best sleeping bag fresh for longer as well as protecting its inner material from dirt and oils. 

This quality liner should last for years with care, and Rab also offer a repair service that extends the life of your kit, which is a more sustainable option than having to splash out on a new one. Despite the price tag, this is definitely one of the best sleeping bag liners, and well worth investing in if you love sleeping in the wild in all seasons.

Rab Ascent Silk Liner: in the field

Of all the sleeping bag liners we've tested recently, this was the most versatile, keeping us comfortable on both warm and chilly nights, and trapping in body heat fast, making drifting off to sleep easier on bitter spring nights. 

We also liked the hood, which sits snugly inside the top of a sleeping bag and stays put, but it won’t hold a small camping pillow in place like some liners with pillow-specific pockets can. 

Rab reckon this liner is mummy-shaped, but on test we found that this tapered bag sat somewhere in between rectangular and mummy shapes. It is a good choice if you want just one liner to fit into all your sleeping bags without having too much extra material bunched up in any design you choose to pair it with. 

There were ten in the pack and the sleeping pad said, "roll over, roll over". So they all rolled over and the bag fell out...

Sleeping bags tend to be the bulkiest items a backpacker will carry, even more so than a tent. If you're heading into the wilderness with your best sleeping bag, a tent, sleeping pad, camping pillow, camping stove, cooking utensils, food, drink and all the other hiking essentials you'll need, your hiking backpack will need to have considerable capacity. It's often the case that not everything will fit inside and it's usually the sleeping bag that gets the boot to the pack's exterior.

This doesn't have to be the case, there are ways to fit everything in, which we'll also cover. However, sometimes you just need to attach your bag on the outside. 

So, we asked two of our backpacking experts to guide you on how to achieve this, detailing several strategies.

How to attach a sleeping bag to a backpack

The best place for your sleeping bag is inside your backpack, as this is where it will be best protected from damage and from getting wet. See ways to store your sleeping bag inside your backpack for more advice on achieving this.

However, if this isn't an option, we've put together 5 methods for attaching your sleeping bag to your backpack:

• 1) Use the lid – fasten your backpack's lid over your sleeping bag, holding it securely in place
• 2) Use the compression straps – loosen your compression straps, slide your sleeping bag in and tighten them up once again
• 3) Use the gear loops – if your sleeping bag stuff sack has adjustable straps, attach these to your backpack's gear loops
• 4) Use bungee cords – hook your cords into the loops on your pack and wind it around both pack and sleeping bag
• 5) Use the tie points at the bottom – many packs come with tie points at the bottom, use these to secure your sleeping bag

It's also worth considering swapping your sleeping bag's stuff sack out for a dry bag, regardless of whether it's inside your pack or outside. This should mean there's less chance of your bag getting wet while you're out and about exploring the backcountry.

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Ways to store your sleeping bag inside your backpack

• Get a larger backpack and learn how to pack it effectively
• Sleeping bags are increasingly packable these days, you may want to invest in one that packs down smaller

First off, it’s worth mentioning that the best place for your sleeping bag is typically inside your backpack if possible. This protects it from weather and snags and also keeps the weight closer to your body, making it easier to carry – check out our guide to packing a backpack for more info. If your sleeping bag doesn’t fit in your pack, there are a few factors to consider. First, is your backpack big enough for your adventure? Take a look at our article on backpack sizes to make sure you have the appropriate sized bag.  

Next up, how packable is your sleeping bag? As gear gets ever more technical, there’s more and more ultralight gear out there. While your old sleeping bag might provide lots of good insulation, it may not pack down very small and end up taking up 3/4 of the space inside your backpack. Some backpacking sleeping bags and camping quilts nowadays pack down to the size of a Nalgene and still keep you toasty at night, so it may be worth investing in a lightweight option, especially if you plan on doing lots of backpacking.

If you’ve got the right size of backpack and a packable sleeping bag and you’re still having trouble making it all fit, it’s also possible that your packing might be the problem. Read our article on how to pack a backpack to learn how to load up and capitalize on the space within your bag without having to forego any essential items. 

Tips on attaching your sleeping bag to your backpack

• Make sure your sleeping bag is protected by a dry bag or similar when attaching
• Make sure it's really tightly secured and snug against your pack

If you’ve tried all of the above and you still can’t make things work with your sleeping bag inside your backpack, you can easily attach it to your backpack. There are several methods for attaching your sleeping bag to your backpack, but for all of them, you’ll want to wrap your sleeping bag in something waterproof like a trash bag. rain cover or dry bag to protect it.

It’s also important to have your sleeping bag tightly secured so you don't lose it, centered and snug against your pack to make it easier to carry. Once you’ve loaded your backpack up, make sure you know how to adjust it properly so it doesn’t hurt your back or slow you down.

Here are five methods for attaching a sleeping bag to your backpack:

Use the lid

Even though your backpack may come with various straps meant for attaching gear, the best place is to use the lid, which is the flap at the top (see: our guide to the parts of a backpack). After you’ve packed your bag and zipped it up, simply open the top flap, place your sleeping bag on top then fasten the flap over it. This keeps your sleeping bag really secure and keeps the weight up high and centered, which makes it easier to carry. If your backpack is already packed to the gills or you have items in the flap pocket, however, this option may not be possible. 

Use the compression straps

Any good hiking backpack will have compression straps – those straps that you can tighten when your backpack is really full to reduce the volume. If your backpack has these, you can loosen the buckles, slide your sleeping bag in and tighten them to secure your bag in place. One downside of this approach is that compression straps are often at the sides of your pack, which means that your backpack may feel uneven on your back. If your backpack has compression straps at the top or bottom, use these ones. 

Use the gear loops

Many hiking backpacks will have gear loops meant for attaching gear like sleeping bags. If you have any at the top of your pack, favor these ones. If your sleeping bag stuff sack has adjustable straps, you can attach the straps to the gear loops on your backpack. For this method, you’ll want to pull the straps tight so the sleeping bag isn’t swinging around behind you. 

Use bungee cords

If your sleeping bag stuff sack doesn’t have any straps, you can use a bungee cord to attach it to the loops on your backpack. Hook the cord into one of the loops on one side of your pack, wind it tightly around your pack several times then book the other end into the other side of your back. 

Use the tie points at the bottom 

Particularly if your backpack has an external frame, it may have tie points at the bottom that are meant for sliding your sleeping bag into. Make sure to tighten these well to avoid your bag swinging around or falling out, and take care any time you set your backpack down since the sleeping bag will be at the bottom. 

If you’re hunting for the best sleeping bag, you should have one primary objective: get the most comfortable one money can buy. You may have noticed that sleeping bags come with a comfort rating, but what does that sleeping bag comfort rating actually mean? Does it refer to how much padding it provides between you and the ground? How warm it keeps you? How easily you can roll over in the night (essential if you’re camping as a side sleeper)? Or a combination of all of the above? In this article, we explain what your sleeping bag comfort rating means so you can select the ideal one for your romps in the wild. 

What does comfort rating mean on sleeping bags? 

Getting a good night’s sleep at camp is key to ensuring you have the energy and positive mindset you need for the following day’s adventures, and while it’s not as easy as when you’re in your own bed, the right sleep system can definitely make or break your chances of sleeping soundly.

Your sleeping bag works in conjunction with your sleeping pad to perform insulation and provide comfort. Since you don’t have your usual bricks, mortar and central heating to keep you warm, you’ll lose body heat quickly when you’re camping, even if the temperatures are relatively mild. Insulation layers help to keep your body heat in, and the colder the overnight temperatures, the more insulating power you need. Clearly, you need a sleeping bag that’s warm enough to be comfortable, but on the other end of the spectrum, you don’t want one that’s too warm either. This is where your sleeping bag comfort rating comes in. 

The temperature rating on your sleeping bag is determined in a lab setting, where each bag is tested with a dummy in the same conditions, such as wearing the same base layers and at the same temperature. Sleeping bags are not required to be tested in this way, but if they have been, it will be indicated as an “ISO” or “En” temperature rating. If you see two sleeping bags made by different brands that both have the same ISO or En temperature rating, you can consider them more or less comparable. However, this scenario doesn’t actually account for all the possible variables, such as what kind of base layers you’re wearing, the R-value of your sleeping pad, the outside temperature and whether you’re a warm or cold sleeper, so consider it a guesstimate at best.

The comfort rating on a sleeping bag is the rating that’s more commonly used on women’s sleeping bags and it indicates the temperature at which you’re likely to be the most comfortable, rather than being the minimum or maximum temperature at which the bag should be used. Men’s and unisex sleeping bags, on the other hand, may instead display a lower limit rating, which indicates the lowest temperature at which the user might still be comfortable, and you’ll notice this is usually a lower temperature than the comfort rating on a women’s bag. This disparity is down to many brand’s assumption that most women are cold sleepers, and you can learn more in our article on women’s vs men’s sleeping bags. 

How to choose a sleeping bag by comfort rating 

First, you need to know the minimum temperature you’re likely to be sleeping in. Then you’ll want to choose a bag with a comfort rating that’s about 10° lower than that to account for variables in conditions as well as your gear and for the fact that many brands will round their temperature ratings up or down to be a multiple of five. Basically, being slightly too warm is not such an issue because you can always unzip your bag and stick a leg out to cool off, but shivering the night away is uncomfortable, if not dangerous.

Temperature is very important when it comes to your sleeping bag, but it isn’t the only factor that plays into your decision. You also need to understand details like the different types of sleeping bag so you choose one that’s the right shape for your sleeping style, and the differences between the fabrics and fill used, so make sure to read our article on how to choose a sleeping bag to make the best decision. 

What is the extreme rating on a sleeping bag? 

Finally, one more rating that sometimes shows up is an extreme rating. This  describes the absolute minimum temperature you can survive in a sleeping bag without succumbing to hypothermia. At that temperature, you wouldn’t actually expect any comfort at all or even to sleep, and it is not advised to use a sleeping bag in these conditions unless it is a last resort in an emergency situation. 

Selk’bag Lite 6G: first impressions

Uniquely brilliant, Selk’bag Lite 6G wearable sleeping bags combine a cosy all-in-one outfit with a good quality kipping cocoon. The result is a perfect solution to cold evenings at the tent, hut or bothy; lightweight bivvying; sleepovers; and regular camping. 

The new Selk’bag Lite 6G is designed to offer maximum comfort and warmth with full freedom of movement. It has full-length arms and legs, a snug hood, and it unzips from neck to waist for easy on/off. There’s a good-sized kangaroo pocket in front that works as a handwarmer or snack stash. A soft-feel polyester outer and hollow-fiber fill feel warm and comfortable to wear. 

Selk’bag suggests the wearable design comes up a couple of degrees colder than a standard sleeping bag of the same weight and fill. But team it up with a good base layer, cinch up the cuffs and hood, and zip on the booties and it’s incredibly cosy. Taking your arms out of the sleeves and sleeping with them next to your body also increases warmth.

Selk’bag Lite 6G: in the field

It’s not hard to imagine the fun our kids had testing these out. They quickly became a firm favorite both inside and outside the tent for play(fight)ing, watching movies and generally putting off getting dressed in the mornings.

But, after a few weeks of more extensive testing, it became clear that Selk’bag’s wearable sleeping bags aren’t really designed as younger children’s sleeping bags. The smallest adult size fits our 10-year-old well (our seven-year-old definitely has some growing to do) but the idea that this is something they’re supposed to sleep in appears to be entirely lost on both of them.

Whether square or tapered, the best sleeping bag with a traditional design offers a gentle but effective means of calming an overexcited child down. Fully zipped up, the most they can do is caterpillar around the tent, which soon gets tiring. Sleeping bags are also deeply associated with sleep – snuggling down at the end of a long day’s adventures is one of the joys we all experience on camping trips. But – at least with our kids – Selk’bags seem to have the opposite effect. 

To be fair, they probably work brilliantly for more chilled-out teens, but the novelty of wearable, warm, padded outfits and everything this enables hasn’t made for particularly restful evenings in the tent. Reading is out and wrestling is in.

In summary, these ingeniously designed suits are perfectly suited to those for whom a relaxed and cosy evening is an essential part of camping. But if you’re camping with younger children, we’d probably suggest sticking with a standard sleeping bag design.

Snugpak Basecamp Explorer: first impressions

A great choice for summer camping trips, the Snugpak Basecamp Explorer is a dedicated children’s sleeping bag designed as an introduction to the Snugpak range. It combines a roomy, square cut around the feet with a cosy drawcord hood and adjustable shoulder baffle, allowing heat to be retained or air to circulate as required. 

There’s no length adjustment, so it’s limited to kids of between about five and 10 years old, depending on height. While it’s fairly heavy for its warmth, the packsize is decent, making it a solid choice for shorter hikes or space-limited car camping trips. Overall, it’s hard to beat for value, and also scores well on versatility, fully unzipping to double as a camping quilt or even a picnic blanket.

Snugpak Basecamp Explorer: in the field

In use, the kids loved the contrast blue/yellow colorway and found the left-side zip easy to grasp and move. The inner is soft and comfortable but the tough outer material is quite noisy as the occupant moves around at night.

Having always been fans of traditional mummy-shaped, tapered sleeping bags, we fully embraced having a fully unzippable square version last summer. The Basecamp Explorer went with us on picnics and out in the garden, as well as on camping trips, proving its versatility as an all-round useful piece of kit that’s perfect for outdoorsy families. 

For use as a sleeping bag, though, it definitely reaches its limits when the weather turns colder. On an chilly visit to Snowdonia National Park complete with sideways rain and considerable windchill, this great-value bag simply didn’t offer enough warmth on its own. Instead, we opted for warmer bags (such as the Deuter Starlight), using the Snugpack in its fully unzipped mode as a cozy blanket over the top. Not the best sleeping bag, but we appreciated its versatility,

Vango Nitestar 150: first impressions

The Vango Nitestar 150 is new for 2021 and arrives at a cracking price even for a one-season sleeping bag. Down-filled rivals may be lighter and smaller than the Vango, with its synthetic insulation, but pound-for-lb this is a really competitive offering.

It’s a mummy-shaped bag with a full-length zip, and a generous foot box that avoids the feeling of claustrophobia from which some bags suffer. It’s wide across the chest, too, although with its zip fastened, shoulder baffle tightened and hood up, the Nitestar proves a snugly warm place to sleep. 

It has a handful of useful features, too, including an internal pocket, zip baffles to stop the zip catching, and hanging loops to peg it up to air, before stuffing it once again into its compression sack. 

Vango Nitestar 150: in the field

If there’s a more demanding test for a sleeping bag than a hiking expedition, it’s surely a bikepacking trip – not only is space severely limited (there’s no chance to hang extra kit on the outside of a pannier) but every extra gram is a curse when the road turns skywards.

So that is exactly the test I put the Vango Nitestar 150 to. Over the course of a busy summer, the Nitestar has been my bikepacking companion on several missions. And it proved to be one of the best sleeping bags for the job, performing well in a variety of conditions.

In terms of warmth, I found it very comfortable. On balmy, summer nights I started the evening with the zip undone, before fastening it as the mercury tumbled after midnight. And on later-to-bed, chilly nights, the Nitestar’s lovely, soft, brushed polyester lining feels comfortingly warm (but is it an ethical down?). 

Eventually, the Vango Nitestar 150 was snaffled by my son for his Duke of Edinburgh Award practice and final expeditions. 

“How did you sleep?” I asked him afterwards. “Well, thanks. Nice sleeping bag,” he replied. Praise indeed from a teenager, and he’s right.

Part of helping your sleeping bag to maintain its performance and warmth is keeping it clean and dry, which can be easier said than done when your roaming the wild and often wet backcountry. However, it's perfectly achievable if you're motivated, which you should be, as quality sleeping bags aren’t cheap, so once you've invested in one, you need to look after it properly. 

Yes, a sleeping bag is one of the most important pieces of kit that you'll ever buy but keeping it clean and washing it when it inevitably does get a little grubby isn't as straightforward as throwing your base layer in the washing machine.

Here we explain how to wash a sleeping bag – along with some other handy tips for keeping it in good working order – to make sure you have many long and happy nights’ sleep in the wilds.

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1. Keep it clean

• Take care not to expose your sleeping bag to dirt while camping
• Don't sit around in it on the ground outside your tent

Show your sleeping bag a bit of love and respect while you’re camping. Don’t walk on it in muddy footwear, keep it away from your boots in the tent, and roll it out carefully across your camping mattress. And don’t hop around the campsite in your sleeping bag like some overgrown caterpillar – sack races ended in primary school! If you need some warmth around the campsite in the evening, pack yourself a camping blanket.

2. Sleep clean

• Make sure you wash yourself before getting into your sleeping bag
• Wear clean clothes and, if necessary, wear a buff if you're hair is unwashed

You may not have showers or even wash facilities when you camp, but there’s still no excuse for clambering into your sleeping bag in sweaty, smelly base layers and socks that you’ve been wearing all day. Give yourself a wash with baby wipes (make sure you wipe off any sunscreen) and change either into a clean set of underclothes that you only use for sleeping throughout your trip, or into the clothes and socks you plan to wear the next day. Use a snood (like a buff) to keep your hike-greasy hair off the bag, too.

3. Use a liner

• A liner can stop your bag getting damp and dirty
• It also adds warmth to the system

A cotton, silk or synthetic sleeping bag liner will add warmth to your sleeping bag, help to keep the bag clean while you sleep, and be much easier to wash at the end of a trip than the sleeping bag itself.

4. Keep your sleeping bag dry

• Keep your bag dry by letting it air during your trip

It’s unavoidable that you will sweat during the night, so if conditions allow, unzip your sleeping bag in the morning and spread it over the tent or hang it from a line to air. Damp bags will always start to smell.

5. Air it out

• Always air your sleeping bag after every trip

At the end of every trip (or each morning if you get the chance), unzip your sleeping bag and hang it up to air on a washing line or over a door. Make sure it’s absolutely dry before you put it away.

6. Don't compress it for long periods

• Never store your sleeping bag in its compression sack
• This is because the insulating fill will lose its performance 

The insulation in sleeping bags, whether down-filled or synthetic, depends on the filling trapping air. As a result, you want to encourage as much air as possible into the insulator in between uses, rather than squeezing the life out of it in a compression stuff sack. More expensive sleeping bags tend to come with two types of carry bags – a loose fitting storage sack and a compression sack for expeditions. Only ever use the storage sack, or perhaps a cotton pillowcase, to store your sleeping bag in between adventures. Alternatively, hang it in a wardrobe or roll it out under your bed (just beware that it might get dusty).

7. Store in a warm, dry place

• Store the bag in a warm, dry room
• Give it a shake and air every few weeks of the off-season

It’s inescapable that your sleeping bag will pick up bacteria from you and your camping trips. Don’t let these bacteria develop into mould and mildew by storing your sleeping bag in a damp place like a garage or garden shed (where it might also attract nesting mice). Keep the bag in a warm, dry room, and give it a shake and air every few weeks of the off-season.

8. Spot clean your sleeping bag

• Use a damp sponge to spot clean any marks or smears that occur as and when they happen

If there’s just a dirty mark, smudge or smear on your sleeping bag, avoid a full-on clean. Use a damp sponge or soft toothbrush with non-detergent soap to work away the grime. Products like Grangers Odour Eliminator can also help to get rid of pongs and refresh your sleeping bag in between washes.

9. Wash your sleeping bag

• Down-filled sleeping bags require different products to synthetic-filled ones
• They both typically require a delicate, low heat wash cycle
• It can be easier to handwash a sleeping bag in the bath
• Tumble dry on a very low setting and allow to air for several days

At the end of the camping season it will probably need a wash, but how to wash a sleeping bag will depend on its insulation. There are specific cleaning products for down sleeping bags, such as Grangers Down Wash and Nikwax Down Wash Direct. These clean and restore the loft to down that has started to compact and bunch, compromising its performance.

For synthetic sleeping bags use a specialist cleaner, such as Nikwax Tech Wash, or soap or a non-biological liquid detergent.

Follow any washing instructions attached to your sleeping bag. Both down and synthetic bags typically require a gentle wash (sometimes labelled as ‘delicate’ or ‘wool’) on a 30°C cycle.

Depending on the size of your washing machine, some people find it easier to hand wash a sleeping bag in the bath, squeezing it gently to get the soap to pass through the insulation. Rinse repeatedly in clean water and then carefully roll up the sleeping bag to drain out the water. Be careful when you lift a sleeping bag out of a bath out that the extra weight of the waterlogged down doesn’t rip any of the baffles.

Drying the bag thoroughly is just as important as the wash. Choose a low temperature on a tumble drier, and check at least every 30 minutes that the sleeping bag is not getting too hot. The aim is to restore the loft of down or synthetic insulation, and adding a tennis ball or two to the drier can help to separate the damp feathers and restore their loft.

It’s worth noting that it can take much longer than you might expect to completely dry a sleeping bag – the down may be damp long after the shell is dry, so set aside several hours for the process. Even then, the sleeping bag will need to be hung up for a few days to air and dry properly before you can store it. If the sleeping bag has a water repellent finish on its shell, hang it up to air inside out.

10. Never dry clean

• Chemicals used in dry cleaning can damage sleeping bags
• However, there are some laundries who offer sleeping bag cleaning services

The chemicals used in dry cleaning can damage sleeping bags, so never resort to this to clean your bag.

However, some specialist laundries do offer dedicated sleeping bag cleaning services. Classic Clean of Harrogate and Mountaineering Designs, for example, will wash and dry a sleeping bag, with a mail order service available. Prices start at about £35 in the UK. In the US, Rainy Pass Repair offers a similar service.

Having a grasp of sleeping bag ratings is crucial when planning your backcountry adventures. Whether you are after high performance, down-filled product for Alaskan expeditions or you’re looking for something a little more affordable for summer camping trips with the family, our expert guide is here to help.

After all, nobody wants to lose half their bodyweight in sweat, tossing and turning in a 800-fill down bag on balmy July nights. Equally, spending a night shivering and suffering in a bag that's simply not warm enough for early spring is not an ideal scenario either. So, it's important to choose the right bag for the right adventures.

The good news is that all bags, from the best sleeping bags to the most basic, go through internationally standarized testing. This is called the International Standard (ISO) and it allows campers to compare like for like when choosing their sleeping bag.

ISO 23537 establishes the range of nighttime air temperatures, measured outside the sleeping bag, at which the sleeping bag will work effectively. This range is typically illustrated in a color chart, running from red at the hottest, through amber and yellow to blue at the coldest. The maximum temperature, or upper limit, is the warmest at which an adult male can have a comfortable night’s sleep without excess sweating. Even with the best tent available, if you don't have a sleeping bag that's rated for the conditions, you may suffer.

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Comfort, Limit and Extreme

The key sleeping bag temperature rating is called ‘Comfort’, which establishes the lowest temperature at which a camper, sleeping in a relaxed position, such as lying on their back, is ‘globally in thermal equilibrium’ – ie not feeling cold.

The ISO also sets a ‘Limit’ sleeping bag temperature rating, at which a sleeping bag user in a curled-up position is ‘globally in thermal equilibrium’ and just not feeling cold.

The ‘Extreme’ sleeping bag temperature rating is only for survival without suffering frostbite, and shows the lowest temperature at which a sleeping bag may prove effective, even if this very low temperature still involves the risk of hypothermia.

Other considerations

Obviously, we strongly recommend choosing a bag that will keep you comfortable, as well as getting yourself one of the best sleeping pads to insulate you from the cold ground below.

It’s important to note that the ratings apply to adults only – ISO says it would be unethical to expose children and babies to such tests. The best children's sleeping bags sometimes have their own rating, but often manufacturers don't display them. Nor do the ratings apply to sleeping bags designed for extreme climate zone conditions.

If you’re unsure of the lowest nighttime temperatures you are likely to encounter on your camping adventures, there is also a more generic labelling system, based on the seasons, just as with one-person tents. Depending on the sleeping bag manufacturer and retailer, there can be as many as six seasons in a four-season year.

One-season sleeping bags

One-season sleeping bags are for mid-summer camping at low-level altitudes, and for tropical travel. They are also good for sleepovers at home. Guides vary, but think temperatures of at least 5°C/41°F.

Two-season sleeping bags

In theory, the operating zone for two-season sleeping bags stretches from late spring to early autumn/fall in the UK, but this window narrows if you’re wild camping in the mountains, where temperatures can plummet overnight. You don't want to have forked out for a sleeping bag only to also need to wear your best down jacket to bed. A rough outside temperature guide would position the limit of two-season sleeping bags for nights of 0/32°F to 5°C/41°F.

Three-season sleeping bags

Designed to keep you warm from early spring to late autumn/fall, these sleeping bags are suited to committed campers happy to be under canvas on frost-free nights when the mercury slips as low as -5°C/23°F. 

The Marmot Phase 30 is a good quality, 3-season bag.

Four-season sleeping bags

These sleeping bags are insulated to keep you warm during winter camping trips at lower levels, typically to temperatures as low as -10°C/14°F. They will also cope with three seasons at higher mountain altitudes, which can become bitterly cold at night.

The Rab Andes Infinium 800 Down Sleeping Bag is a superb 4-season bag.

Five-season

Expeditions to the world’s coldest climes, whether high-altitude mountaineering or even to the poles, demand the exceptional insulation of five-season (also known as four-plus season) sleeping bags to contend with temperatures as low as -40°C/-40°F. Five-season sleeping bags have the highest grade construction and insulation.

First impressions

Rab’s most recent marketing tagline trumpets the brand as ‘masters of insulation’. That’s a pretty bold claim, but the Rab Neutrino Pro 400 has the specs to back it up.

It’s filled with high-quality 800 fill power goose down that offers impressive warmth-for-weight as well as packability, reflecting its intended use as a specialist mountaineering piece, where every gram and cubic inch counts.

• Explore the best sleeping bags in our buying guide
• Get a comfortable night's sleep with the best sleeping pads
• Not sure how to choose a sleeping bag? We can help you out

However, it’s too good a sleeping bag to be reserved solely for elite climbers, particularly since so many of the features that enable the Pro to excel in high alpine environments mean it is also brilliant for backpackers and wild campers too.

That applies even in damp UK weather, since hydrophobic fill and a water-resistant shell makes it far more resistant to moisture than most down bags.

In the field

We really appreciated the Neutrino Pro’s generous length and extra room for the upper torso, and so too will anyone who is over six foot or slightly broader of chest. 

The bag tapers to a contoured footbox, which leaves less room for the lower limbs, but this is still a comfortable bag to lie in. It’s also very cosy, thanks to a shaped hood and contoured footbox, plus chunky zip and collar baffles.

We were impressed by the bag’s meticulous design and excellent quality of construction too – Rab have clearly thought carefully about how to build the best bag possible within the parameters of weight and packability. For example, the down chambers are arranged in chevrons, which helps to hold the fill over the centre of the body and prevent it from migrating (which often causes cold spots).

Similarly, we loved this bag’s extra little details, like the handy internal stash pocket and the ‘noctilucent’ zip puller – which means it glows in the dark to you and me. The practical roll-top stuff sack compresses well too, ensuring it packs easily into a rucksack. In fact, for us, this is pretty much the perfect three-season bag.