A sleeping bag that keeps you warm in the cold weather, doesn’t get too hot in warmer climates, weighs nothing, costs next to nothing, packs small and looks good. Yes, please!
Read on for our guide to choosing not simply the best sleeping bag, but the best sleeping bag for you.
Latest update: October 2020
There’s no need to spend a fortune. It’s all about knowing whether you need lightness, superior warmth or just a basic sleeping bag.
If you’re planning to bivvy half-way up a snowy mountain, then you won’t be buying a £15 sleeping bag from Aldi. If you’re a casual camper, it’s unlikely you’ll want to pay £200+ for an expedition-quality sleeping bag. Most of us, though, fall somewhere in between – wanting a good compromise between cost and comfort.
This guide doesn’t cover the cheap, festival-type bags, nor the high-end technical kit. Instead, we’ve been looking at well-designed, comfortable and affordable bags that you can rely on.
We took a budget of between £30 and £150. This might seem a little high, but we aimed to find three-season options that would stand up to fairly regular use and would last for years and years. Bear in mind that three seasons in the UK won’t include late autumn or early spring – so essentially, we’re looking at May to October. We set a maximum weight of around 2,5kg.
So, read on for the best three-season sleeping bags. And if you need something extra warm, zoom right to the end for our three top four-season cold weather sleeping bags.
You really don’t need this guide…
If you camp a couple of times a year in spring, summer or early autumn and don’t have to carry your kit on your back, then virtually any sleeping bag will do the job.
Our advice would be to set a budget and then choose a bag that’s as close to the comfort of home bedding as you can get.
Some people prefer to camp with a duvet. They can be bulky, so finding one that’s light and warm is the trick. Don’t go for a feather or down one as they’re horrid when damp (and unkind to birds).
Rectangular sleeping bags
For a sleeping bag that’s as close to home bedding as possible, go for a rectangular bag like the ones shown below. Cotton will feel nicer than nylon.
One of the newer quilt-like sleeping bags will give you more versatility. These bags tend to be heavier (up to 3.5kg) and won’t make small packs.
If you want more versatility, then consider a cross between a duvet, a sleeping bag and a poncho – like the Vaude Navajo (see the recommendations below).
Double sleeping bags
We personally don’t like double sleeping bags because the packs are larger and you don’t get the versatility of having two separates.
However, there are some temptingly warm ones around like the Highlander Serenity double mummy bag (above) with a comfort rating of 0C (read about ratings further down).
And the beautifully designed Sierra Designs Backcountry and Frontcountry range.
Our choice for duvet-style sleeping bags
Everyone loves their Jungle Blanket
We’ve had a lot of readers singing the praises of the Snugpak Jungle Blanket. It’s insulated, easy to wash, folds small, works well as a cover in warm weather and even better as an additional layer when it’s cold. Wrap up in it by the campfire too. Weighs from 300g, four sizes and from around £25.
A cotton or silk sleeping bag liner can keep you from sticking to cheaper, shiny bags. It can add a layer of warmth, or it can keep you covered if you need to unzip to let some cool air in. Plus, you’ll be able to wash it more easily, saving you from washing your bag too often.
How about a sleeping pod?
A few companies make cosy sleeping pods that should keep you warm through two-three seasons. They’re quirky-looking oval sleeping bags.
Remember that extra room inside means they won’t be quite as warm as a close-fitting mummy bag with good insulation. However, they certainly are comfortable to sleep in.
And now for our favourites – our top ten sleeping bags
A clever option that can be a sleeping bag and a blanket. It’s a spacious, warm rectangular sleeping bag made with environmentally friendly bluesign® certified materials. The Sensofiber fill reflects body heat yet efficiently transfers moisture away from the body. Two can be connected. Very cosy. Choice of warmth ratings with the 900 our three-season choice.
- Comfort 2°C and limit -3°C
- Pack size: 25 x 30
- Weight: 1.8kg
- Length: 220cm
The design of the Smoozip is really different with the curvy zip, but it was the fleece lining that won us over. There’s a women’s version that’s usually cheaper and also a range of temperature ratings to choose from.
- Comfort 1°C and limit -5°C
- Pack size: 44 x 25
- Weight: 1.8kg
- Length: 190cm
The Nemo Forte range includes men’s and women’s options and a choice of temperature ratings.
- Comfort not stated. Limit -7°C
- Pack size: 36 x 22
- Weight: 1kg
- Length: 163/183cm
- Comfort 3°C and limit -3°C
- Pack size: 53 x 30cm
- Weight: 2.3kg
- Length: 198cm
Double layered insulation and the option to open the foot-end. Trucomfort by name and nature! We love these and other Kelty bags. They’re so beautifully designed.
Often on offer, so you might get it more cheaply. There’s a lovely double too.
- Comfort -4°C and limit -7°C
- Pack size: 30 x 37cm (single)
- Weight: 1.4kg
- Length: 183cm
Warm and breathable because it’s made from organic cotton (poly filling). You can pull up the hood for complete cosiness, or convert the bag into a duvet. Two can also be zipped together. Heavy, though!
- Comfort 0°C and limit -5°C
- Pack size: N/A
- Weight: 2.9kg
- Length: 200cm
Lots of attractive features on this very affordable sleeping bag. Not a well-known brand, but seemed warm and two can be zipped together. We’d argue it wasn’t 4-season as described, but definitely three.
- Comfort 15°C, limit 0°C
- Pack size: 37 x 26cm
- Weight: 1.4kg
- Length: 220cm
Wouldn’t I be warmer in a mummy sleeping bag?
Sleeping bags keep you warm by trapping your body heat in an enclosed space. That’s why expedition bags are always tight mummy-shapes.
This type of bag can be claustrophobic, though, especially for people who move around a lot in their sleep. Rectangular bags, like the ones we mentioned above, are great when weight and size don’t matter.
For the in-between campers, though, the compromise is a slightly larger mummy-style – sometimes called a comfort-fit mummy. These may have a bit more width and a wider foot area.
If you’re taller than average, look for bags that come in a longer length. Some manufacturers make women’s versions, which will be shorter and have a bit more width in some areas.
Weight and size
We’d like to have included this Mountain Warehouse Sutherland in our top picks, but it’s a 3.7kg beast. It’s advantage – apart from the fact it’s £55 – is that it has a fleece lining and will keep you comfortable when the temperature drops to 3°C.
Choosing a bag that’s warmer than you need will add weight. In fact, unless you’re backpacking, weight probably matters less than pack size. Even when packing a car for camping or using a campervan, you’ll want to save space.
While we’re on the subject of packing your sleeping bag – don’t leave it compressed in its sack for long periods or you’ll damage its ability to hold heat.
Waterproofing and washing
Only sleeping bags made for extreme conditions and for bivvying will be properly waterproof. Many good sleeping bags, though, are treated with durable water repellent (DWR), which causes water to bead on the outer shell rather than soak in. It will wear off after time and washing.
Sleeping bags stuffed with synthetic fibre are easy to wash in the machine. They’re best dried outside in the sun and wind, but they can go into the dryer too. Don’t use too high a heat and turn the bag inside out half-way through the cycle. It can be hard to tell if the insulation is completely dry, so leave it out to air for as long as you can.
Temperature ratings and the seasons
Our first tip is an easy one – choose a bag that offers you a bit more warmth than you think you’ll need.
You never know when you might want to camp at chillier times, and it’s easier to unzip and leave a leg out in the breeze if you get too warm than it is to start adding layers if you’re cold. However, there’s no point in adding bulk and weight with too warm a bag if you’ll never sleep in near-zero conditions.
Manufacturers usually show a ‘comfort’ rating
- Upper limit – the highest temperature that a ‘standard’ man would be comfortable without sweating, with arms outside the bag and the bag unzipped.
- Comfort – the temperature a ‘standard’ woman can expect to sleep comfortably.
- Lower limit – the temperature that our ‘standard’ man can sleep for eight hours in a curled position without waking up.
- Extreme – the limit at which the bag will keep you alive. It’s NOT an indication of the lowest temperature at which you could use the sleeping bag comfortably. Most of us (Arctic explorers aside) can ignore this rating and focus only on the comfort guide.
The lowest rating shown by manufacturers tends towards optimism. We’d always add on a little to be on the safe side.
The other way of rating sleeping bags is using seasons. Remember, though, that it also depends on where you’re sleeping. Having slept in a bivvy hammock on April 1 in Yorkshire, I can tell you that a three-season bag is not warm enough. If you’re on an insulated mat inside a warm tent or in a campervan, then you’ll probably be fine.
- Season one is summer in mild climates
- Season two is like UK late spring to early autumn
- Season three is chilly nights but without frost
- Season four is cold winter nights with frost or snow.
Our recommended three-season bags have a comfort rating that will allow for some cold weather nights (under canvas or in a campervan).
Why we’ve chosen a synthetic filling
We started to write a section about the differences between down and synthetic fillings – down is lighter in weight for equivalent warmth, but more expensive and harder to care for; synthetic tends not to keep its fluffiness for as long, but isn’t as affected by damp conditions, and so on.
But here’s why down isn’t a good choice for most of us campers.
Very few of us need the weight reduction that down offers. More importantly, can we sleep well wondering if the down has been plucked from live (and terrified) birds or from birds force-fed for foie gras?
We’ve come across a number of manufacturers who don’t just abide by codes of ethics for sourcing their down, but are very specific about not using live-plucked or foie gras by-products.
Rab, for example, say their down “is traceable under the European Down & Feather Association Codex. This code of conduct determines the source of down; ensuring that it is a byproduct of a slaughterhouse or harvested during moulting periods and not illegally live plucked”.
Katabatic give access to a Track my Down programme to trace the down’s provenance.
Patagonia, Montane and Marmot are among the others. Some companies, however, are vague with their reassurances of “sustainable methods” and “supply chain control”. Thermarest, interestingly, say nothing about their down production, but their bags are made in China.
If you really want down (and nothing insulates as well), then here’s the order of priority
2. Harvested from moulting or nests
3. Plucked from birds slaughtered for meat
Here’s more info on down production, and don’t forget to put the manufacturer or retailer on the spot by asking the question before buying.