The Great Outdoors team test the best 3-season (spring to autumn) sleeping bags to the test and pick out the best. 

A three-season sleeping bag is a type of sleeping bag designed to provide warmth and comfort during the spring, summer, and fall seasons. The best sleeping bags will typically be rated for temperatures between 20 and 40 degrees Fahrenheit (-6 to 4 degrees Celsius) and will be designed for use in weather conditions that are not extremely cold or hot.

As well as considering the outside night-time temperature on a camping trip, it’s important to take into account your personal comfort levels. We’re all different and some of us are ‘cold sleepers’.

Women are more likely than men to sleep colder at night, largely explained by physiological differences, including, on average, lower muscle mass. Hormonal fluctuations will also affect women’s core body temperature at different times of the month and through the menopause.

best three-season sleeping bags

Fill type, construction, warmth, weight and packability are all important aspects to consider when choosing a sleeping bag.

Age makes a difference, too. Both men and women are likely to suffer a decrease in the body’s circulation capacity as we age, as the walls of our blood vessels lose their elasticity. When blood moves more slowly through the body, our extremities tend to feel the cold more quickly.

So, it’s worth paying close attention to the lower end temperature ratings – sometimes called the ‘comfort limit’ – as a rough guide to temperature performance. Look for zoned areas of warmth, too – in particular the foot box, hips, and hoods with baffles around the shoulder, neck and face.

In this comparative test of the best sleeping bags on the market right now we look at everything to make sure that you have the most informed decision possible when purchasing your next sleeping bag.

In case of interest, we’ve recently compiled a similar assessment of the best alternatives to sleeping bags and the best hiking boots too.


The best 3-season sleeping bags for 2023

The following list shows the best sleeping bags for men and women, all suitable for three-season camping. Each item has been extensively tested and reviewed by our expert gear team and rated for its performance, value, durability, feature set and the balance between weight and warmth.

  1. Rab Women’s Neutrino 400 | $400 / £400 | Best buy for women
  2. Therm-a-Rest Parsec 20F/-6 | $499 / £430 | Recommended for Women
  3. Sierra Designs Women’s Night Cap 20 | $180 / £160 | Recommended for Women
  4. Kelty Women’s Cosmic Synthetic 20 | $110 / £90 
  5. Sea to Summit Ascent Acl-4 | $399 / £320 | Best buy for men
  6. Robens Icefall Pro 900 | $200 / £190 | Recommended for men
  7. Nordisk Oscar -2° Curve | International shipping / £296
  8. Deuter Orbit -5° | International shipping / £115
  9. Mountain Equipment – Helium 600 | $469 / £280 | Best buy for women
  10. Rab Women’s Ascent 700 | $315 / £270 | Recommended
  11. Robens Serac 600 No U.S. shipping / £276
  12. PHD M.Degree 400 K custom-made | $1044 / £882
  13. Alpkit Cloud Peak 300 | $130 / £110 | Best budget women’s sleeping bag
  14. Mammut Perform Down Bag | $400 / £355 | Best buy sleeping bag
  15. Mountain Equipment Firelite | $700 / £500 | Recommended
  16. Marmot Helium | $479 / £375
  17. Rab Neutrino 600 | $475 / £440
  18. Thermarest Parsec | $352 / £360 | Best budget sleeping bag for men

How we tested them

The products here were all assessed by Fiona Russell, Peter Macfarlane, Lucy Wallace & James Roddie

Fiona is a US size 8 (UK 10) and is 5 foot 6 tall. She is a cold sleeper. She walked and wild camped with the bags (and used the same inflatable sleeping mat) in the mountains and glens of the Scottish Highlands. To test the DWR (durable water repellent), she poured on water and applied a little pressure and movement. The product weights are taken from Fiona’s own digital scales.

Peter Macfarlane slept in the bags in the same woodland bothy and using the same sleep mat to achieve some consistency in judging the overall performance. Peter is six feet tall with a 44” chest and comments on fit are based on his sizing. Peter tested for water resistance to spills and condensation by applying clean water and light pressure. Weights are from his scales.

Lucy Wallace is 171cm tall with narrow shoulders. She sleeps cold, so likes a warm bag. Her bags were tested in winter and spring conditions in Scotland and the Lakes, both wild camping and in a campervan. Weights including stuff sack were measured on Lucy’s digital scales. 

James Roddie is 180cm tall with average-width shoulders. He tends to be a ‘cold sleeper’, and he has taken this into consideration. He tested the sleeping bags in a variety of conditions in the Scottish Highlands during the spring – in overnight temperatures ranging from around +2°C to +9°C. He weighed the sleeping bags (including stuff sacks) using his own digital scales.   

Rab Women’s Neutrino 400

RAB 400 sleeping bag review and rating

  • Rating: 4.5/5
  • Price: $400 / £400 ( Buy now from LD Mountain Centre)
  • Weight: 849g
  • Pros: Light and warm
  • Cons: Expensive, snug fit for taller women

Fill: 400g 800FP Nikwax hydrophobic RDS European goose down | Shell: 20D Pertex Quantum recycled nylon ripstop | Construction: trapezoidal box wall | Zip: ¾-length YKK two-way anti-snag | Length: 200cm | Rating: comfort -1°C, limit -7°C | Sizes: one | Men’s version: yes


This latest edition of Rab’s Neutrino 400 sleeping bag was launched in 2022. It features chevron-shaped baffles, an improved drawcord system, a small pocket inside the hood, and a snag-resistant two-way zip. The women’s version is smaller than the men’s, but it is narrower at 156cm girth. The bag is filled with European goose down, certified by the Responsible Down Standard, at Rab’s factory in the UK. The tough Pertex Quantum used both inside and outside the bag is made from recycled materials and is fluorocarbon-free. It is a premium down bag for lightweight use in the shoulder months and even winter.

Read Lucy’s full review of the Rab Women’s Neutrino 400

Therm-a-Rest Parsec 20F/-6

Therm-a-Rest Parsec sleeping bag review

  • Rating: 4/5
  • Price: $499 / £430 ( Buy now from Alpine Trek)
  • Weight: 935g
  • Pros: Very warm for weight, three sizes available
  • Cons: Expensive

Fill: 470g 800FP Nikwax hydrophobic RDS down | Shell: 100% recycled nylon ripstop DWR | Construction: box wall | Zip: ¾-length two-way YKK anti-snag | Length: 203cm (regular) | Rating: comfort 0°C, limit -6°C | Sizes: small, regular, long | Men’s version: no, unisex


The Therm-a-Rest Parsec -6 is a high-quality down sleeping bag that was tested in very soggy conditions. It has nice details such as a cosy pocket for feet in the bottom, a large zipped pocket on the outside, and removable straps underneath. The mummy hood is deep and luxurious, and the neck baffle isn’t adjustable. The bag is not available in men’s and women’s versions, but Therm-a-Rest produces three sizes. The regular size is generous in length (203cm) and fairly narrow (157cm girth), and a reasonable fit overall. The shell and liner are made entirely from recycled materials and filled with Responsible Down Standard down.

Read Lucy’s full review on the Therm-a-Rest Parsec 20F/-6

Sierra Designs Women’s Night Cap 20

Therm-a-Rest Parsec sleeping bag review.

  • Rating: 3.5/5
  • Price: $180 / £160 (Buy now from Amazon)
  • Weight: 1626g
  • Pros: Versatile, especially for warm sleepers
  • Cons: Zipless design can lead to draughts

 Fill: 1276g recycled Sierraloft Eco Synthetic | Shell: 20D recycled polyester Construction: synthetic fill | Zip: none | Length: 188cm | Rating: comfort +1°C, limit -5°C | Sizes: one | Men’s version: yes


Sierra Designs has pioneered innovative zipless bag designs, such as the Nightcap 20. The wrapover shape creates versatility for warm sleepers who like to vent through the night and allows for spreading out a bit if needed. The drawback is that it can fall open with too much movement, leading to draughts. The bag includes a sleeping mat sleeve on the base and a neck baffle, and the Eco Synthetic fill is made from recycled water bottles and the shell is recycled. Overall, it is clever and warm, with a smaller environmental footprint than many other synthetic bags, and some will love the versatile comforter system.

Read Lucy’s full review on Sierra Designs Women’s NightCap 20

Kelty Women’s Cosmic Synthetic 20

Kelty Women’s Cosmic Synthetic 20 sleeping bag review

  • Rating: 3/5
  • Price: $110 / £90
  • Weight: 1856g
  • Pros: Good value, warm
  • Cons: Heavy, not very compressible

 Fill: 1300g CirroLoft | Shell: 380T nylon taffeta | Construction: synthetic fill | Zip: Kelty’s own brand ¾-length two-way | Length: 188cm | Rating: comfort -4°C, limit -11°C | Sizes: one | Men’s version: yes

The Cosmic 20 synthetic sleeping bag is a good value for warmth and overall price. It features generous but non-adjustable front and back neck baffles, and a drawcord to keep heat in around the face. It is 188cm long and wide around the footbox, providing some wiggle room for side sleepers. It is heavy at 1856g, but Kelty’s proprietary CirroLoft synthetic fibres do feel stiff and bulky, and its minimum pack size is 41x25cm, making it best suited to car camping.

Read Lucy’s full review on Kelty Women’s Cosmic Synthetic 20

Sea to Summit Ascent Acl -4

Sea to Summit Ascent Acl -4 sleeping bag review

  • Rating: 4/5
  • Price: $399 / £320 ( Buy now from Alpine Trek)
  • Weight: 926g
  • Pros: Warm, packs down very small, hydrophobic down fill.
  • Cons: Expensive

Fill: 330g 750FP Ultra-Dry down | Shell: 20D ripstop nylon | Construction: side block baffle | Zip: 2-way, full-length on left, 2-way, 1/3-length on right | Length: 205cm (regular) | Rating: comfort +2°C, limit -4°C | Sizes: regular, long | Women’s version: no


The Ascent is a mid-point between a mummy and a semi-rectangular bag. It has a generous lofting sack and an ultralight compression sack. It has 330g of 750 fill power Ultra-Dry hydrophobic down and Sea to Summit claims it can dry out 60% faster than untreated down. The hood is generous and can be tightened down. The bag has a zip on the right-hand side and a foot box ventilation zip, but its insulation did not extend along the length of the foot box zip. Overall, the Ascent is a very attractive option, warm, lightweight and suitable for a wide variety of conditions.

Read James Roddie’s full review on Sea to Summit Ascent Acl-4

Robens Icefall Pro 900

Robens Icefall Pro 900 sleeping bag review

  • Rating: 4/5
  • Price: $200 / £190 (Buy now from Amazon)
  • Weight: 1495g
  • Pros: Very warm and comfortable, versatile centre zip design
  • Cons: Heavy, long with no shorter option

Fill: 900g MicroThermo Ball 600FP polyester | Shell:  20D ripstop nylon | Construction: box wall | Zip: 2-way, near-full-length in centre | Length: 220cm | Rating: comfort 0°C, limit -5°C | Sizes: long Women’s version: no


The Icefall Pro 900 is the warmest sleeping bag in this review due to its 900g MicroThermo Ball synthetic insulation. It is aimed at taller people and has a high waist drawcord to keep the warmth in. It has a zip in the centre of the bag, which makes getting in and out of the bag much easier and allows for even ventilation over the core. There is no side ventilation zip, but it is easy to undo the zip almost to the feet and use the bag like a quilt in warmer conditions. Whilst quite heavy and lacking a shorter version, the Icefall Pro 900 is a well-designed three-season bag, particularly if you prioritize warmth and comfort.

Read James Roddie’s full review on Robens Icefall Pro 900

Nordisk Oscar -2° Curve

Nordisk Oscar -2° Curve sleeping bag review

  • Rating: 3.5/5
  • Price: International shipping / £296 (Buy now from Alpine Trek)
  • Weight: 940g
  • Pros: Lightweight, small size when packed away, 100% recycled synthetic filling made from recycled PET bottles
  • Cons: Expensive, zip-pulls small and fiddly

Fill: NorGuard S-PO s-core fibre | Shell: 7D ripstop nylon | Construction: offset double box wall | Zip: 2-way, 3/4-length on left | Length: 205cm (large)  | Rating: comfort +4°C, limit -2°C | Sizes:  medium, large, extra-large | Women’s version: no


The Oscar -2° Curve is a lightweight and very packable three-season sleeping bag. It is supplied with two different carry sacks, a dry-sack and an extremely lightweight bag made from the same ripstop nylon as the sleeping bag shell and lining. The shell and lining material feels soft, comfortable and very thin. The ‘curve’ shape of the bag is described by Nordisk as ‘the optimal balance between insulation and space’. The bag includes ventilation zips on both the right shoulder and foot box. The hood and draught collar are both easily adjusted, and the head felt nicely insulated on cold nights. It tested down to temperatures of +4°, and while other sleeping bags felt warmer in comparable conditions, the Oscar -2° Curve is a good option for three-season backpacking when size and weight are crucial considerations.

Read James Roddie’s full review on the Nordisk Oscar -2° Curve

Deuter Orbit -5°

Deuter Orbit -5° sleeping bag review

  • Rating: 3/5
  • Price: International shipping / £115
  • Weight:1830g
  • Pros: Warm, affordable price, highly durable
  • Cons: Heavy, large when packed away

Fill: 900g high-loft hollowfibre | Shell: 50D Rec Pes ripstop | Construction: 2-layer | Zip: 2-way, full-length on left |Length: 205cm (regular) | Rating: comfort +1°C, limit -5°C | Sizes: regular, large | Women version: yes


The Deuter Orbit -5° is a warm, affordable three-season sleeping bag that is not aimed at lightweight backpackers. It is large and heavy, but it is well-insulated and has a thick baffle and draught collar to keep warm air in. The hood is warm, but it does not extend over the top/front of the head as much as it would like. The main two-way zip features a large pull, making it easy to find and use during the night. The anti-snag zip guard is an effective feature, as snagging zips is a common annoyance with sleeping bags. For general three-season camping, this is a warm and affordable sleeping bag, but it is large and heavy, and if carrying it whilst backpacking you will notice the weight quickly.

Read James Roddie’s full review on the Deuter Orbit -5°

Mammut Perform Down Bag – Best buy

best three-season sleeping bags: Mammut perform down bag

  • Rating: 4/5
  • Price: $400 / £355 (Buy now from Alpine Trek)
  • Weight: 2.35 lb. / 1005g
  • Pros: Comfort, performance, price
  • Cons: Centre zip not for everyone, weight

Temperature comfort limit: 19.4°F / -7°C | Materials: 700 fill power ethically certificated duck down, polyester/nylon lining, nylon outer | Features: box wall construction, mummy shape, full-length two way centre zip, shoulder baffle, internal pocket, stuff and storage sacks. Comes with ear plugs and sleep mask. | Size: long | Women’s version: unisex


The Mammut Perform Down Bag comes with a different approach when compared to the other bags as it has a full length centre zip. The relaxed mummy fit allows for a good amount of movement, without there being lots of dead air space reducing efficiency. It’s very well insulated and the large internal pockets is big enough to store most items. The Mammut Perform is a brilliant bag for camping and offers a comfortable sleep.

Read Peter Macfarlane’s full Mammut Perform Down Bag review.

Mountain Equipment Firelite

best three-season sleepings bags: Mountain Equipment Firelite

  • Rating: 4/5
  • Price: $700 / £500 (Buy now from Alpine Trek)
  • Weight: 1.68 lb. / 764g (Regular)
  • Pros: Weight, comfort, performance
  • Cons: Price

Materials: 900 fill power ethically certificated goose down, nylon shell | Temperature comfort limit: 16°F / – 9°C | Features: slant box wall construction, mummy shape, stretch seams, full-length two-way zip, shoulder baffle, stuff sack and storage sack | Sizes: regular, long | Women’s version: yes


The Firelite is one of the lightest bags in this review, but it maintains a strong performance with very high quality down and light shell fabric. The weight of the bag means it’s great for longer hikes and high camps outside of winter. However all of this comes at a cost with it being the most expensive within the best mens sleeping bags test. 

Read Peter Macfarlane’s full Mountain Equipment Firelite review.

Marmot Helium

best sleeping bags: Marmot Helium

  • Rating: 3/5
  • Price: $479 / £375 (Buy now from Alpine Trek)
  • Weight: 2.11 lb. 958g (Regular)
  • Pros: Comfort, price
  • Cons: No shoulder baffle

Materials: 800+ fill power ethically certificated goose down, Pertex Quantum 20D 100% nylon ripstop | Temperature comfort limit: 10.5°F / -12°C | Features: box wall construction, mummy shape, full length two way zip, internal pocket, stuff sack, storage sack | Sizes: regular, long | Women’s version: Xenon


The helium offers quite a neat fit without restricting movement, A well shaped foot box and warm hood which can be cinched with an external draw cord. There’s an easy to operate access zip, but this sadly snags on occasion, despite anti-snagging strips. Perfectly placed internal pocket allows easy access to torches and the like. There’s no shoulder baffle or drawcord for your chest making it difficult to completely seal yourself in.

Read Peter Macfarlane’s full Marmot Helium review.

Rab Neutrino 600

best three-season sleeping bags: Rab Neutrino 600

  • Rating: 4/5
  • Price: $475 / £440 (Buy now from Alpine Trek)
  • Weight: 2.24 lb. / 1020g (Regular)
  • Pros: Comfort, performance
  • Cons: Weight

Materials: 800 fill hydrophobic, ethically certificated down; Pertex Quantum outer, nylon inner | Temperature comfort limit: 10°F / -12°C | Features: box wall construction, mummy shape, shoulder baffle, full-length two-way zip, internal pocket, stuff sack, storage sack | Sizes: regular, long, wide, long wide | Women’s version: yes


The Neutrino has got the joint lowest temperature rating in this comparative test with a comfort limit of 10.4°F (-12°C), making it perfect for winter expeditions. This means slightly more weight than others on test but the Neutrino is packed with features and comfort to make that extra few grams worth it. 

Read Peter Macfarlane’s full Rab Neutrino review.

 

Therm-a-rest Parsec -6

best three-season sleeping bags: Thermarest Parsec

  • Rating: 4/5
  • Price: $352 / £360 (Buy now from LD Mountain Centre)
  • Weight: 1.99 lb. / 906g (Long)
  • Pros: Comfort, performance, price
  • Cons: Top bag design not for everyone

Materials: 800 fill power hydrophobic, ethically certificated down, nylon shell | Temperature comfort limit:  20°F / -6°C | Features: box wall construction, mummy shape, top bag design, shoulder baffle, full-length two-way zip, external pocket, stuff sack, storage sack | Sizes: small, regular, long | Women’s version: unisex


The Thermarest Parsec is the last bag on our list for the best sleeping bags for men and it’s one of our top performers. The Parsec is a top bag which means the Hood, foot box and the rest of the bag has insulation, however your back has very little. In turn this saves some weight and lets you customise your performance by having a mat to cover the missing areas. An effective baffle, roomy fit and external draw cords to cinch the hood means you’ll be getting a good nights sleep.

Read Peter Macfarlane’s full Therm-a-rest Parsec review.

Mountain Equipment women’s Helium 600 – Best buy

Mountain Equipment women's Helium 600 best buy

  • Rating: 5/5
  • Price: $469 / £280 (Buy now from Alpine Trek)
  • Weight: 2.23 lb. / 1012g (Long)
  • Pros: Warmth, attention to detail, female-specific
  • Cons: Incorrect weight

Materials: 700 fill power 90/10 duck down; shell and lining: 100% recycled 20D nylon | Temperature: ‘Good Night’s Sleep’ temperature 18°F / -8°C  | Features: women’s Alpine fit with zoned EXL system, slanted box-wall baffles throughout, five-baffle anatomically shaped hood, four-baffle anatomically shaped and offset foot-box, choice of regular left or right zip or left long zip, neck collar with Lode Lock closure, waterproof roll-top stuff sack, storage cube | Sizes: regular (maximum user height 170cm), long (185cm) | Men’s version: yes


Mountain Equipment have made some big claims when it comes to their Helium series of sleeping bags. There are a wide abundance of features, from the choice of two lengths and zoned system that encloses the bag around your body to cut out dead air space. The 600 is reasonably priced and lightweight but not at the expense of comfort which is why we’ve given it our best buy award.

Read Fiona Russell’s full Mountain Equipment Helium 600 Women’s review.

Rab women’s Ascent 700

best three-season sleeping bags: Rab women's Ascent 700

  • Rating: 4/5
  • Price: $315 / £270 (Buy now from Ultimate Outdoors)
  • Weight: 2.74 lb. / 1243g
  • Pros: Warmth, attention to detail, female-specific
  • Cons: Weight, stuff sack

Materials: 650 fill power RDS-certified European duck down with Nikwax PFC-free hydrophobic finish; shell: 100% recycled 30D Pertex Quantum with PFC-free durable water repellency; lining: 100% recycled 20D nylon | Temperature: Rab sleep limit: 15°F / -9°C | Features: wide mummy shape, trapezoidal box wall construction, 3D-shaped neck collar, three-quarter long main zip with down-filled baffle, anti-snag zip insert and anti-snag internal zip guard, zipped internal stash pocket, angled foot box, drawcord stuff sack, zipped cotton sack with water-resistant base for home storage | Sizes: regular, 200cm long, user height 170cm maximum | Men’s version: yes


Next on our list of the best sleeping bags is the Rab Women’s Ascent 700. This sleeping bag is 50g lighter than the mens version due to a narrower shoulder and foot width. This light and cosy bag comes with a 15°F (-9°C) comfort rating, which should give you confidence even if you’re a cold sleeper. Zipped stash pockets at neck height are an appreciated feature, however we’d like to see a longer version of this bag available.

Read Fiona Russell’s full Rab Women’s Ascent 700 review.

Robens Serac 600

best three-season sleeping bags: Robens Serac 600

  • Rating: 3/5
  • Price: No U.S. shipping / £276 (Buy now from Alpine Trek)
  • Weight: 2.38 lb. / 1080g
  • Pros: RDS-certified duck down, compressible stuff sack
  • Cons: Warmth, pack size

Materials: 600 fill power RDS-certified duck down 85/15; shell: 20D 400T nylon ripstop; lining: 20D 400T nylon taffeta | Temperature: comfort 19.4°F / -7°C | Features: mummy shape, face and neck baffle, full-length insulated zip, easy-adjust hood drawcord, loft expander design for increased warmth, shark-fin foot box, compression stuff sack, mesh storage bag | Sizes: short, 200x85x53cm, body length 175cm; other lengths: 195cm | Men’s version: unisex


This lightweight and fluffy sleeping bag from Robens, is not the warmest of bags on test making it hard to recommend when sleeping in any temperatures below freezing. A roomy width, with plenty of insulation in the neck baffle. A well worked foot area means it works well for people with larger feet. The Serac is definitely more of a luxurious choice designed for summer nights.

Read Fiona Russell’s full Robens Serac 600 review.

PHD M.Degree 400 K custom-made

best three-season sleeping bags: PHD M.Degree 400 K custom-made

  • Rating: 4/5
  • Price: $1044 / £882
  • Weight: 1.21 lb. / 550g (Standard custom-made)
  • Pros: Warmth, custom-fit and custom-made, weight
  • Cons: Price

    Materials: 1000 fill power European goose down; shell and liner: 7X ripstop nylon with DWR | Temperature: comfort 15.8°F / -9°C | Features: customised to suit customer size and needs; choice of four lengths and four widths; half and full-length zip, right or left, dual-construction design, oval-shaped footbox, various add-on options at extra cost including waterproof footbox/outer shell, stuff bag, mesh storage bag | Size: 16 sizes, depending on requests | Men’s version: unisex


Made start to finish in the UK the PHD M.Degree 400k sleeping bag is the most expensive bag that we have tested. The eye watering price can be explained as 95% of materials and components are sourced within Europe to minimise global transportation. The sleeping bag is also fully custom-made and fits like a glove when in use. It’s also the lightest and warmest bag that we’ve tried specifically made for people who demand the best warmth to weight ratio, however it comes at a costly price.

Read Fiona Russell’s full PHD M.Degree 400 K custom-made review.

Alpkit Cloud Peak 300

best three-season sleeping bags: Alpkit Cloud Peak 300

  • Rating: 3/5
  • Price: $130 / £110
  • Weight: 3 lb. / 1405g
  • Pros: Price, synthetic fill
  • Cons: Weight, pack size

Materials: 300gsm Thermolite T3E-ML Ecomade fill; outer fabric: 40D nylon 300T ripstop; lining: 20D polyester | Temperature:  Alpkit sleep comfort limit:  17.6°F / -8°C,| Features: synthetic polyester-based insulation using 35% recycled content, outer fabric with PFC-free water repellency, choice of left or right zip, insulated zip baffle, hood with neck baffle and adjuster, compression bag, machine-washable | Size: regular, 165cm to 180cm | Men’s version: unisex


The Alpkit Cloud Peak 300 is an ethical version for anyone looking for a goose down sleeping bag due to its synthetic fill. It offers a roomy width and length as well a neck baffle and thick zip baffle. However, this is a much heavier bag compared to the others we have tested which is something worth thinking about. For just over £100 it does score well on the weight to warmth ratio, so worth considering if you’re working to a budget.

Read Fiona Russell’s full Alpkit Cloud Peak 300 review.

What makes a good sleeping bag?

1. Insulation: down versus synthetic

Sleeping bags use either down or synthetic insulation. Down fill is lighter and warmer for its weight and packs smaller, but loses performance when wet.

It comes in different qualities and fill weights, which affects performance and price. Synthetic fill is less compressible for packing but retains performance when wet.

2. Temperature ratings

In addition to the brands’ own temperature usage recommendations, it’s always worth checking sleeping bag temperature ratings. These are Comfort, Comfort Limit and Extreme.

Comfort indicates a temperature where you can expect a good undisturbed sleep; Comfort Limit is as low as you can expect a decent night’s sleep; and Extreme indicates the temperature where the bag should keep you safe but not comfortable enough for a night’s sleep. 

3. Construction

A down bag’s performance comes from its ability to allow the fill to ‘loft’ – to expand fully – trapping as much air as possible to retain body heat. Box wall construction aims to maintain an even density of insulation around your body but adds bulk and manufacturing expense; stitch-through construction is lighter and cheaper but allows cold spots.

4. Entry

Sleeping bags’ entry options range from full-length zips to half zips to no zips at all. Longer zips give easier access and let you cool off; shorter zips can get you a smaller pack size; zipless bags can be tricky to get into in small tents.

Main zips should have baffles to prevent heat loss.

5. Hood

Hoods vary greatly in style but can be vital on colder camps. The most basic are lightly insulated with a simple drawstring around your face whilst some are fully insulated and formed to give maximum protection.

6. Shoulder baffle

There is often an internal baffle that can be tightened around your shoulders to trap the warm air inside the bag. Easy adjustment of this feature is important.

7. Sleeping bag Fit

Most bags have a tapered ‘mummy’ shape, being widest at the shoulders and narrowing down to the foot.

Female and male bag designs account for different body shapes, and improves thermal efficiency by removing dead space. The amount of taper varies and can affect user comfort depending on your natural sleep position.

8. Footbox

Good footboxes are shaped to accommodate your feet whilst allowing insulation to fully loft to maintain warmth.

9. Pack size & weight

In the hills a compact, lighter bag will make life easier; for campsite use a heavier, bulkier bag may be less of an issue.

10. Additional sleeping bag features

Some bags have pockets, useful for keeping camera batteries warm or stashing a headtorch where it’s handy.

Are sleeping bags washable?

Sleeping bags work most efficiently when they are clean. Dirt can impede their performance. However washing can also harm a sleeping bag and so should only be done when absolutely essential.

How easy it is to wash a sleeping bag depends on the fill. It’s not difficult with synthetic fills, quite a bit harder with down. Whichever type you have it’s worth taking precautions so that it doesn’t need washing very often.

  1. Sleep in clean clothes or a liner bag.
  2. Air your bag whenever possible. A few hours in the open can work wonders.
  3. Make sure your bag is stored loosely and there is air flow round it to prevent it getting musty.
  4. Spot clean dirty marks or sweat stains with a soft sponge and soap and water then wipe away any residue with a soft cloth.

Before washing any bag always check the care instructions.

Are synthetic sleeping bags washable?

Synthetic bags can be washed in a front-loading washing machine.

  1. Check the bag for any tears. Don’t wash the bag until these have been repaired.
  2. Run a wash cycle in the washing machine to remove any remaining detergent or fabric conditioner.
  3. Open zips and close Velcro tabs.
  4. Use non-biological detergent, pure soap, or a specialist product like Nikwax Tech Wash.
  5. Use a gentle, cool setting and a short spin. Heat can damage the bag.
  6. Tumble dry on a low heat setting or drape the bag over a clothes horse, ensuring strain isn’t put on the seams.

Are down sleeping bags washable

Washing a down bag takes time and requires care. Washing can be done by hand or in a machine. For drying a tumble drier is essential. The first steps are the same for machine and hand washing.

  1. Check the bag for any tears. Don’t wash the bag until these have been repaired.
  2. Open zips and close Velcro tabs.
  3. Use pure soap, or a specialist product like Nikwax Down Wash, Grangers Down Wash or Storm Down Wash. Don’t use detergent.

Machine Washing a sleeping bag

  1. Run a wash cycle in the washing machine to remove any remaining detergent or fabric conditioner.
  2. Wash on a gentle, cool setting (30°) with a low to medium spin speed.
  3. Rinse twice or more.

Hand Washing your sleeping bag

  1. Fill a very large tub – a bath is ideal – with warm water.
  2. Gently press the bag into the water until it’s saturated.
  3. Wash the bag carefully and gently with your hands. Don’t lift it out of the water.
  4. Rinse, rinse, and rinse again until the water is clear.

How to dry your sleeping bag

  1. Lift the bag carefully out of the machine or bath. To avoid putting a strain on the seams or baffles cradle it in your arms.
  2. Place the bag in a tumble drier.
  3. Add some tennis balls or similar as these will help break up the down and stop it clumping.
  4. Tumble dry on the lowest heat setting.
  5. Be patient! Drying can take several hours.
  6. Remove the bag from the drier often and gently break apart any clumps of down.