Best Backpacking Sleeping Bags 2026

Three-Season Backpacking Sleeping Bags, Including Best Ultralight, Cold and Warm Weather, Synthetic, Wide And Tall, and Budget Options

June 4th, 2026, updated with three new winners, new bags tested, and a new section on how we tested including new testing notes
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A backpacking sleeping bag is one of the three pieces of gear that determines whether you sleep well or lie awake shivering, and unlike a tent or a pad, the bag is what's in direct contact with your body all night. The difference between a good bag and the right bag comes down to how conservative the temperature rating actually is, how well the insulation performs when compressed or damp, and how the cut fits your body while you're inside it rather than on a store shelf.

We've tested backpacking sleeping bags over thousands of miles and hundreds of nights across the Sierra Nevada, the Rocky Mountains, the Pacific Northwest, and desert trails, with testers of different shapes, sizes, sleep styles, and cold tolerances putting the same bags through the same conditions side by side. Testing included nights down to 10 degrees to verify warmth claims that don't always hold up under real conditions.

What separates a genuinely good backpacking sleeping bag from one that leaves you cold or uncomfortable comes down to whether the temperature rating is accurate or optimistic, how the fill power and fill weight work together to deliver warmth at low weight, how well the cut balances roominess with thermal efficiency, and how the bag performs after repeated compression and washing over seasons of use.

Top Pick: The Feathered Friends Swallow UL 20 (men's) and Feathered Friends Egret UL 20 (women's) earn our Best Overall award. They stood out for 950+ fill power down that lofts better than any other bag we tested, a conservative warmth rating that our testers have verified down to 10 degrees, a generous cut that feels comfortable without being oversized, a lifetime warranty, and handmade construction from Feathered Friends' Seattle factory that justifies the price over a bag that needs replacing every few years.

Looking for even lighter? Check out our Best Ultralight Sleeping Quilts guide.

Looking for more affordable bags? See our Best Camping Sleeping Bags guide


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Comparison tables

Men’s Sleeping Bags

SLEEPING BAG TREELINE AWARD TEMP RATING EN/ ISO COMFORT EN/ ISO LOWER TOTAL WEIGHT FILL WEIGHT FILL POWER WATER-RESIST DOWN SHOULDER GIRTH LENGTHS MSRP
Feathered Friends Swallow UL 20 Best Overall
Read why
20°F N/A N/A 26.6 oz 16.8 oz 950+ No 60.0" 72, 78" $659-679
REI Co-op Magma 15 Best Budget
Read why
15°F 21°F 9°F 35.6 oz 23.3 oz 850 Yes 61.5-70" 65, 71, 77" $419
Western Mountaineering SummerLite Best Ultralight
Read why
32°F 41°F 32°F 19.0 oz 9.0 oz 850+ No 59.0" 66, 72, 78" $520-555
Feathered Friends Lark 10 UL Best for Cold Sleepers
Read why
10°F N/A N/A 31.3 oz 20.0 oz 950+ No 60.0" 72, 78" $709-729
Sea to Summit Reactor Extreme Liner Best Summer Sleeping Bag
Read why
Adds up to 10°F N/A N/A 12.8 oz N/A N/A N/A 62.0" 78, 85" $80-85
NEMO Forte 20 Endless Promise Best Synthetic
Read why
20°F 30°F 19°F 53.0 oz Not stated N/A No 59.0" 72, 78" $200-260
Western Mountaineering MegaLite Best Wide and Tall
Read why
30°F 32°F 22°F 24.0 oz 12.0 oz 850+ No 64.0" 66, 72, 78" $595-630
NEMO Disco 30 Endless Promise Best for Side Sleepers
Read why
30°F 40°F 30°F 31.0 oz 11.0 oz 650 Yes 62.0" 72, 78" $280-320
Western Mountaineering UltraLite 20°F 25°F 14°F 29.0 oz 16.0 oz 850+ No 59.0" 66, 72, 78" $640-685
REI Co-op Zephyr 25 25°F 28°F 17°F 48.0 oz N/A N/A No 58-75" 65, 71, 77" $189-209
Western Mountaineering VersaLite 10°F 21°F 9°F 32.0 oz 20.0 oz 850+ No 62.0" 66, 72, 78" $755-790
Western Mountaineering AlpinLite 20 20°F 25°F 14°F 31.0 oz 19.0 oz 850+ No 64.0" 66, 72, 78, 84" $720-790
SOURCE: Manufacturers

Women’s Sleeping Bags

SLEEPING BAG TREELINE AWARD TEMP RATING EN/ ISO COMFORT EN/ ISO LOWER TOTAL WEIGHT FILL WEIGHT FILL POWER WATER-RESIST DOWN SHOULDER GIRTH LENGTHS MSRP
Feathered Friends Egret UL 20 Best Overall
Read why
20°F N/A N/A 27.2 oz 17.3 oz 950+ No 57" 63, 39" $629-649
REI Co-op Magma 15 Best Budget
Read why
15°F 21°F 9°F 35.6 oz 23.3 oz 850 Yes 61.5-70" 65, 71, 77" $419
Western Mountaineering SummerLite Best Ultralight
Read why
32°F 41°F 32°F 19.0 oz 9.0 oz 850+ No 59.0" 66, 72, 78" $520-555
Feathered Friends Petrel 10 UL Best for Cold Sleepers
Read why
10°F N/A N/A 32.3 oz 21.3 oz 950+ No 57" 63, 39" $669-689
Sea to Summit Reactor Extreme Liner Best Summer Sleeping Bag
Read why
Adds up to 10°F N/A N/A 12.8 oz N/A N/A N/A 62.0" 78, 85" $80-85
NEMO Forte 20 Endless Promise Best Synthetic
Read why
20°F 21°F 8°F 58.0 oz 50 oz N/A N/A 60-68" 66, 72" $200-250
Western Mountaineering MegaLite Best Wide and Tall
Read why
30°F 32°F 22°F 24.0 oz 12.0 oz 850+ No 64.0" 66, 72, 78" $595-630
NEMO Disco 30 Endless Promise Best for Side Sleepers
Read why
30°F 31°F 21°F 36.0 oz 16.0 oz 650 Yes 60-68" 66, 72" $280-300
Western Mountaineering UltraLite 20°F 25°F 14°F 29.0 oz 16.0 oz 850+ No 59.0" 66, 72, 78" $640-685
REI Co-op Zephyr 25 25°F 28°F 17°F 48.0 oz N/A N/A No 58-75" 65, 71, 77" $189-209
Western Mountaineering VersaLite 10°F 21°F 9°F 32.0 oz 20.0 oz 850+ No 62.0" 66, 72, 78" $755-790
Western Mountaineering AlpinLite 20 20°F 25°F 14°F 31.0 oz 19.0 oz 850+ No 64.0" 66, 72, 78, 84" $720-790
SOURCE: Manufacturers


The Best Backpacking Sleeping Bags

Best OVERALL MEN’S Backpacking Sleeping Bag: Feathered Friends Swallow UL 20

Feathered Friends Swallow UL 20

Temperature Rating: 20°F (not EN rated)
Total weight (oz): 26.6
Fill Weight (oz): 16.8
Fill Power: 950+
Hydrophobic Down? No
Fabric: Pertex Quantum Pro 7D
Shoulder (in) / Hips (in):  60” / 56”
Traceable/Responsible Down: Yes
What we liked: Conservative warmth rating, incredible loft, good sizing options, draft collar
What we didn't like: Expensive

The Feathered Friends Swallow is our winner for best sleeping bag for men for three years running. Feathered Friends is a well-loved sleeping bag manufacturer for good reason. Their bags are simply top-notch and backed by a lifetime warranty. Every review — both professional and customer — found these bags to be very warm (better than the rated temp). 

After 5 years of carrying the Swallow mummy bag on backpacking trips in the Sierra, Rocky Mountains, and Pacific Northwest, our own testing backs that up. Our testers also liked that unlike many other ultralight sleeping bags, the cut is generous enough to feel comfortable without being oversized. The Swallow is a time-tested and beloved backpacking sleeping bag, and it's our pick for the best overall men’s backpacking sleeping bag.

We think this is the best lightweight sleeping bag you can get for backpacking that actually provides warmth. Not all "20-degree sleeping bags" are equal. With a more than accurate temperature rating, the Swallow is the best 20 degree sleeping bag out there, which we think is the ideal temperature rating for a 3-season backpacking sleeping bag. And while there's a lot of down sleeping bags for backpacking, this one is the best due to its high quality down. 

View The Swallow UL 20

Best Women's Backpacking Sleeping Bag: Feathered Friends Egret UL 20

Feathered Friends Egret UL 20

Temperature Rating: 20°F (not EN rated)
Total weight (oz): 27.2 oz
Fill Weight (oz): 17.3 oz
Fill Power: 950+
Hydrophobic Down? No
Fabric: Pertex Quantum Pro
Shoulder (in) / Hips (in): 54” / 56”
Traceable/Responsible Down: Yes
What we liked: Comfortable, incredible loft, good sizing options, draft collar, insulated zipper baffle, wide in hips
What we didn't like: Expensive

The Feathered Friends Egret is our winner for best sleeping bag for women. 

I had previously thought a women’s sleeping bag was utter nonsense (what could be that different?), but after testing the Egret UL 20, now I am a believer. 

My hips and feet were always cold spots when testing other bags. The thoughtful design of the Feathered Friends Egret mummy bag addresses these common issues. Women’s cut bags expand the range of sizes accommodated, especially in the hip area where traditional cut bags can be restricting for women and wide shoulder areas can feel drafty. 

We're increasingly seeing brands move away from manufacturing "women's bags" so applaud Feathered Friends for the thoughtfulness in the Egret. 

No matter what the label says, you'll be better off choosing a bag with the best fit for your body. If you are anywhere between 5'6" and 5'9 in height, we recommend the Egret.

We think this is the best lightweight sleeping bag you can get for backpacking that actually provides warmth. Not all "20-degree sleeping bags" are equal. With a more than accurate temperature rating, the Egret is the best 20 degree sleeping bag out there, which we think is the ideal temperature rating for a 3-season backpacking sleeping bag. And while there's a lot of down sleeping bags for backpacking, this one is the best due to its high quality down. 

View The Feathered Friends Egret

Best budget Backpacking Sleeping Bag: REI Co-Op Magma 15

REI Co-Op Magma 15

Temperature Rating (F), EN ISO/ISO Lower Limit: 15, 21/9
Total weight (oz): 35.6
Fill Weight (oz): 23.3
Fill Power: 850
Hydrophobic Down? Yes
Fabric: Recycled ripstop nylon
Shoulder (in) / Hips (in): 62.5” / 54”
Traceable/Responsible Down: Yes
What we liked: Quality materials and features at more affordable price
What we didn't like: Not as warm as marketed

If dropping $500+ on a sleeping bag is just not going to happen, the REI Co-op Magma 15 is a solid choice. At the time of writing, the Magma 15 was the bestselling sleeping bag at REI. The bag retails at $419, and you can save more if you time your purchase with an REI sale or coupon promotion.

The Magma boasts some impressive stats that are comparable to the Feathered Friends and Western Mountaineering bags we recommended for our Ultralight and Wide & Tall Picks. It’s constructed with lightweight 15D Pertex fabric and 850 fill down. It also has a solid zipper that doesn’t snag and a nicely shaped foot box.

View the REI Co-Op Magma 15

Best Ultralight Sleeping Bag: Western Mountaineering Summerlite

Western Mountaineering Summerlite

Temperature Rating (F), EN Comfort/EN Lower Limit: 32, 41/32
Total weight (oz): 19
Fill Weight (oz): 9
Fill Power: 850+
Hydrophobic Down? No
Fabric: 20D nylon ripstop, DWR coating
Shoulder (in) / Hips (in):  59” / 51”
Traceable/Responsible Down: Yes
What we liked: Lightweight, great weight-to-warmth ratio
What we didn't like: Fits snug

The Western Mountaineering SummerLite is our winner for Best Ultralight Sleeping Bag. It is the brand's lightest sleeping bag with baffle construction. It weighs only 19 ounces–impressive for fully baffled hooded mummy bag rated to 32F degrees. The bag is fully insulated with 10 ounces of 900 fill power down fill. Our research and testing on over 1000 miles on the Pacific Crest Trail and another 1000 miles on the Continental Divide Trail in early summer suggests a comfort rating of 32 degrees seems reasonable.

We found that when it starts getting colder, you'll want a liner, a more insulated sleeping pad, or another bag. But for those summer trips where weight and space are at a premium, it's hard to beat the Summerlite in terms of warmth-to-weight ratio of a true zip sleeping bag (as compared to a quilt–more on that below).

Compare Prices Of The Western Mountaineering Summerlite

Best Sleeping Bag for Cold Sleepers: Feathered Friends Lark 10 Ul (Men’s) and Petrel 10 Ul (Women’s)

Feathered Friends Lark 10 UL

Temperature Rating (F), EN Comfort/EN Lower Limit: 10 (not EN rated)
Total weight (oz): 31.3/ 32.3
Fill Weight (oz): 20/ 21.3
Fill Power: 950+
Hydrophobic Down? No
Fabric: Pertex® Quantum Pro
Shoulder (in) / Hips (in): 60” / 56” (men’s) and 54” / 56” (women’s)
Traceable/Responsible Down: Yes
What we liked: Warm and comfortable
What we didn't like: Not recommended for mountaineering

The Feathered Friends Lark 10 UL (men's) and Petrel 10 UL (women’s) sleeping bags have been favorites among some of our testers, particularly for cold weather. That is why the Feathered Friends Lark and Feathered Friends Petrel win our award for best sleeping bag for cold sleepers.

The Lark and Petrel are like taking the Swallow and Egret, but making them even warmer. At a 10 degree rating and made with 950+ goose down, these bags are Feathered Friends’ warmest 3-season options. The Lark weighs 31.3 ounces and the Petrel at 30.2 ounces. 

Our tester switched to the Lark 10-degree bag for the last few months of his Appalachian Trail thru-hike, which he finished towards the end of December. The Lark helped him sleep comfortably during the long nights of winter in Appalachia and live out his dream of finishing the Triple Crown.

Compare Prices Of The Feathered Friends Lark 10 Ul And Petrel 10 Ul

Men's
Women's
The Feathered Friends Lark 10 is a true 10F bag. Our tester used it on a late season thru-hike of the Appalachian Trail ending in December.

The Feathered Friends Lark 10 is a true 10F bag. Our tester used it on a late season thru-hike of the Appalachian Trail ending in December.

Best summer sleeping bag for backpacking: Sea To Summit Thermolite Reactor Extreme Sleeping Bag Liner

Sea To Summit Thermolite Reactor Extreme Sleeping Bag Liner

Temperature Rating (F), EN Comfort/EN Lower Limit: adds 10F (not EN rated)
Total weight (oz): 12.8
Fill Weight (oz): N/A
Fill Power: N/A
Hydrophobic Down? N/A
Fabric: 110g/m2 Thermolite fabric
Traceable/Responsible Down: N/A
What we liked:
Lightweight, affordable, versatile
What we didn't like: Not for cold weather (unless used with a sleeping bag)

Recommending a sleeping bag liner as the best summer sleeping bag is a bit cheeky. We know. But the reality is if you’re backpacking where it’s warm, buying an expensive sleeping bag may not be worth the cost and added weight.

Sleeping bag liners – ideal for adding degrees of warmth to your sleeping bag rating – are versatile in that they can serve as warm weather sleeping accommodations as well. 

Of the liners out there, we think the Sea to Summit Thermolite Reactor Extreme Sleeping Bag Liner is an affordable and practical warm weather sleeping bag for those hot, humid summer days when you only need a little extra warmth. 

We've used the Reactor in summer backpacking in Appalachia and also while traveling in tropical destinations like Costa Rica and Thailand. It's everything you need to cut the chill at the deepest part of the night and nothing more. 

However, if you are backpacking in the summer at altitude, in cold places like Iceland, or during freak storms, this liner isn't going to be enough warmth. So check the weather, conditions, and temperature and if adding 20-25 F to the low is around what you like to sleep at, this may be a good (and affordable) option.

Sea To Summit Thermolite Reactor Extreme Sleeping Bag Liner

Best Synthetic Sleeping Bag: Nemo Forte 20 Endless Promise

Top view of the NEMO Forte 20 Sleeping Bag

Temperature Rating (F), ISO Comfort/ISO Lower Limit: 20, 30/19 (men’s), 20, 21/ 8 (women’s)
Total weight: 55 oz (men’s), 58 oz (women’s)
Fill Weight (oz): 32 (men’s), 50 (women’s)
Fill Power: N/A
Hydrophobic Down? N/A
Fabric: 100% recycled 30-denier ripstop polyester
Shoulder (in) / Hips (in): 64” / 59” (men’s) and 62” / 58” (women’s)
Traceable/Responsible Down: N/A, but fill is recycled
What we liked: good for side sleeping, vegan, affordable, easy venting for warmer days
What we didn't like: heavy

A popular sleeping bag for its comfort, the NEMO Forte 20 Endless Promise sleeping bag is our winner for Best Synthetic Sleeping Bag. This bag has an ISO tested comfort rating of 30 degrees for men and 20 degrees for women, and ISO tested lower limit of 19 degrees for men, and 10 degrees for women. It also has some of the best sustainability initiatives we've seen on a bag.

As a synthetic bag, the NEMO Forte will stay warm when wet. But unlike many synthetic sleeping bags out there, this is highly technical and well-designed bag for serious backpackers. 

We backpacked with this bag on a snowy spring trip in Colorado and found it warm even in just below freezing temperatures.

The NEMO Forte is also the most sustainable backpacking sleeping bag out there. It's part of NEMO's Endless Promise program. The idea is that it is made of recycled materials and at the end of its life, it can be fully recycled.

We like this bag so much we wrote an in-depth review NEMO Forte Endless Promise so you can learn more about it.

Compare Prices Of The Nemo Forte 20

Men's
Women's
Tester Meg Carney in the Nemo Forte Endless Promise sleeping bag.

Tester Meg Carney in the Nemo Forte Endless Promise sleeping bag.

Best Wide & Tall Sleeping Bag: Western Mountaineering Megalite

Western Mountaineering Megalite

Temperature Rating (F), EN Comfort/EN Lower Limit: 30, 32/22
Total weight (oz): 24
Fill Weight (oz): 12
Fill Power: 850+
Hydrophobic Down? No
Fabric: 12D Extremelite
Shoulder (in) / Hips (in): 64 / 56
Traceable/Responsible Down: Yes
What we liked: Size-inclusive, comfortable, accurate temperature rating
What we didn't like: Expensive

The Western Mountaineering MegaLite is a highly lauded bag among reviewers from one of the most trusted sleeping bag brands. Western Mountaineering is a trusted brand with decades of experience making high-quality down sleeping bags. Of all their many high quality bags, we appreciate the MegaLite for its size-inclusivity, particularly for its increased spaciousness at the shoulders.

Compare Prices Of The Western Mountaineering Megalite

Best Backpacking Sleeping Bag For Side Sleepers: Nemo Disco 30 Endless Promise

A picture of the top view of a NEMO Disco 30 Endless Promise in the men's version

Temperature Rating (F), ISO Comfort/ISO Lower Limit: 30, 40/30 (men’s); 30, 31/21 (women’s)
Total weight (oz): 31-36
Fill Weight (oz): 11-16
Fill Power: 650
Hydrophobic Down? Yes
Fabric: 30D nylon ripstop
Shoulder (in) / Hips (in): 62” / 57” (men’s) and 60” / 56” (women’s)
Traceable/Responsible Down: Yes, RDS certified
What we liked: Affordable, lots of features
What we didn't like: Heavy

The NEMO Disco Endless Promise is one of the most beloved sleeping bags out there. It is one of the heaviest bags in our review, but has some clever features that we think are worth your attention. The NEMO Disco uses a Thermo gill design on the top so you can vent heat during warm weather.

This is a popular choice for the comfort for backpackers of all shapes and sizes. If you’ve ever felt cramped and restricted in traditional sleeping bags, this is the bag for you. The Disco Endless Promise bag is spacious and suited for stomach or side sleepers. It's also significantly less expensive than other backpacking sleeping bags at $280. 

We also think it makes an excellent option for folks who want one bag for camping and backpacking that can do it all. Based on Treeline writer Gabi Reyes-Acosta’s experience, it was the overall winner of our Best Sleeping Bag in our Best Plus Size Outdoor Gear guide, where you can learn more about other gear options that work for bigger bodies.

Check out our in-depth review of the NEMO Disco Endless Promise to learn more.

Compare prices of the Nemo Disco 30 Endless Promise

Men's
Women's
Nemo Disco sleeping bag

other sleeping bags we tested

The Western Mountaineering UltraLite in royal blue.

Temperature Rating (F), EN Comfort/EN Lower Limit: 20, 25/14
Total weight (oz): 28-30
Fill Weight (oz): 15-17
Fill Power: 850+
Hydrophobic Down? No
Fabric: 12D Extremelite
Shoulder (in) / Hips (in): 59 / 51
Traceable/Responsible Down: Yes
What we liked: Continuous baffles allows down to move where needed, high quality construction
What we didn't like: Narrow cut, doesn’t pack down well

The Western Mountaineering UltraLite is a beloved bag for many, with an impressive 17 ounces of fill weight in the 6’ 6” bag and great warmth-to-weight ratio. Like the Feathered Friends bag, it has a draft collar and zipper tube. However, for our testers the cons outweigh the pros. The cut is narrow, but yet it doesn't pack down well. And it's expensive. For us, the Feathered Friends is a better choice, as it’s warmer and weighs a little less.

Plus, as Treeline Review Editor-in-Chief notes, “the women’s design Feathered Friends is roomier in the hips but narrower in the shoulders.” You can find a more detailed comparison of the two sleeping bags in our Favorite Gear for a PCT Thru-hike piece. The Western Mountaineering Ultralite is also available in a similar wide model called the Western Mountaineering Alpinlite. The Ultralite is featured in our Outdoor Gear that will Last for Life guide for its extraordinary quality and craftsmanship.

Compare Prices Of The Western Mountaineering Ultralite


Exped DeepSleep 20

Temperature Rating (F), EN Comfort/EN Lower Limit: 34/20F
Total Weight: 4 lbs 0.4 oz
Fill Weight/ Fill Power: N/A Synthetic insulation
Hydrophobic Down? N/A synthetic insulation
Fabric: 100% recycled polyester (monomaterial construction)
Shoulder (in) / Hips (in): 64” / 55”
Traceable/Responsible Down: N/A, but fill is recycled

The Exped DeepSleep sleeping bag is a premium-feeling synthetic sleeping bag at a budget price. It is less expensive than the REI Magma, which is made of more expensive down. It is also less expensive than the NEMO Forte, which is a synthetic bag. The DeepSleep has a LowerLimit temperature rating of 20 whereas those other bags are more comfortable at 20F.

The Exped DeepSleep straddles the line of camping sleeping bag and backpacking sleeping bag. It comes with a compression sack—which usually costs $40 extra—and is compact enough for backpacking and camping. It's a good option for first backpacking bag and we'd recommend it as a best backpacking sleeping bag for beginners who don't want to invest in a high end bag (that being said, we think a backpacking sleeping bag is one piece of gear where you should invest to get the best you can). That being said, we think you'd be hard-pressed to find a sleeping bag that offers a better value.

Read more in our in-depth review of the Exped Deep Sleep Sleeping Bag.

Exped DeepSleep 20


REI Zephyr 25 Recycled

Temperature Rating (F), ISO Comfort/ISO Lower Limit: 25, 28/17
Total weight (oz): 48
Fill Weight (oz): N/A
Fill Power: N/A
Hydrophobic Down? N/A
Fabric: Recycled ripstop nylon (bluesign® approved)
Shoulder (in) / Hips (in): 66.5” / 57” 
Traceable/Responsible Down: N/A, but fill is recycled
What we liked: Recyclable synthetic insulation (vegan), comfortable, affordable
What we didn't like: Heavy

If you’re looking for a solid synthetic sleeping bag, the REI Zephyr 25 is another good choice. Made from 100% recyclable synthetic fill polyester insulation, the Zephyr 25 is comfy and compressible. 

Like the NEMO Forte, this sleeping bag is on the heavier end of those we tested at 3 lbs for the medium size. This weight may not be ideal for ultralight backpackers, but it’s still a nice synthetic and more affordable option if the weight isn’t a dealbreaker.

View The Rei Zephyr 25


Western Mountaineering Versalite

Temperature Rating (F), EN Comfort/EN Lower Limit: 10, 21/9
Total weight (oz): 32
Fill Weight (oz): 20
Fill Power: 850+
Hydrophobic Down? No
Fabric: 12-denier ripstop nylon
Shoulder (in) / Hips (in): 62” / 53”
Traceable/Responsible Down:
Yes

We're big fans of the Western Mountaineering VersaLite. With high-quality materials, this made in the USA bag is one of the best on the market. Ultimately, we found the fit not as good as good on other bags, especially a more size-appropriate women's bag. This is still an excellent option, especially if you are interested in a 10F bag.

View the Western Mountaineering Versalite


Western Mountaineering Alpinlite

Temperature Rating (F), EN Comfort/EN Lower Limit: 20, 25/ 14
Total weight (oz): 31
Fill Weight (oz): 19
Fill Power: 850+
Hydrophobic Down? No
Fabric: 12-denier ripstop nylon
Shoulder (in) / Hips (in): 64” / 55”
Traceable/Responsible Down:
 Yes

The Western Mountaineering AlpinLite bag is very similar to the Western Mountaineering MegaLite that was chose as best Big and Tall sleeping bag. It's made of the same high quality materials, Made in the USA construction, and conservative warmth rating.

The difference is that the AlpinLite is designed to be a wider version of Western Mountaineering's popular 20F UltraLite (review above). The MegaLite, on the other hand, is a wider cut of a 30F bag. In our experience, most folks who want a wider cut say they run warm. Thus, we think if you're looking for a big and tall bag, you can save carrying some weight and money by going with the MegaLite instead. But, if you run cold or are headed to colder climates or high alpine conditions, consider the Alpinlite instead.

View the Western Mountaineering Alpinlite


Treeline Review writer and photojournalist Dean Krakel captured this photo of his Colorado Trail hiking partner mid-yawn as he cowboy camped (slept in his sleeping bag without a tent). Photo by Dean Krakel.

Treeline Review writer and photojournalist Dean Krakel captured this photo of his Colorado Trail hiking partner mid-yawn as he cowboy camped (slept in his sleeping bag without a tent). Photo by Dean Krakel.

What’s The Difference Between a Backpacking and a Camping Sleeping Bag?

This article focuses on the best sleeping bags for backpacking, as opposed to car camping or sleeping on a friend’s couch. The backpacking sleeping bags mentioned here would also serve well for summer mountaineering and alpine climbing trips. If you're primarily camping, you may be able to save money by checking out our Best Camping Sleeping Bags guide, or opting for our winners for best camping-backpacking synthetic bag, the NEMO Disco Endless Promise (review above).

The lightweight fabrics and high fill power down of a backpacking sleeping bag equate to a high price tag. When presented with all the options, it may seem silly to buy a bag that costs 2-3 times more than other options. 

However, this is one area where there is near universal agreement among experienced outdoors people: of any piece of gear you want to invest in, it’s a sleeping bag. A quality bag that is taken good care of will last for decades (yes, decades!).

There is near universal agreement among experienced outdoors people: of any piece of gear you want to invest in, it’s a sleeping bag. A quality bag that is taken good care of will last for decades (yes, decades!).

Down insulation is graded by how much it expands, creating pockets to trap air and, therefore, insulate. Called "loft" in the industry, think of it as “floofiness.” 

The “fill power” number is how many cubic inches of space one ounce of the down takes up. So, one ounce of 800 fill down takes up 800 cubic inches of space (think 3.5-gallon jugs of milk). 

800-950 fill power is on the higher end of what geese can produce. While there are 1000 fill power down options, such as in the NEMO Pulse Ultralight Quilt or Mountain Hardwear’s $1700 mountaineering mummy suit, this is the extreme upper end and very expensive due to its limited supply. The amount of this down that would be necessary to fill a sleeping bag is cost-prohibitive (did you see that mummy suit?), so it’s not used in this application.

All bags for this review use down that is not live-plucked from the birds. Some brands have also committed to higher standards of animal welfare, certifying their down sources through the Responsible Down Standard, or their own program.


Treeline Review co-founder Liz Thomas snapped this photo of her hiking partner Moni in a sleeping bag in a tent on the Continental Divide Trail in Colorado. Photo by Liz Thomas.

When traveling in snow or colder conditions, pay attention not just to the temperature rating on your sleeping bag, but also on your sleeping pad. Treeline Review co-founder Liz Thomas snapped this photo of her hiking partner Moni on the Continental Divide Trail in Colorado. Photo by Liz Thomas.

FAQ

Drying out a sleeping bag on the Pacific Crest Trail. Photo by Amanda Jameson.

Drying out a sleeping bag on the Pacific Crest Trail. Photo by Amanda Jameson.

What to look for in a sleeping bag

To narrow down the very wide field of sleeping bags into our finalists list, all 12 sleeping bags that made our contender list had to meet the following criteria:

Temperature Rating Between ~20-30F

This range is appropriate for typical 3-season use (late spring to early fall in most places), covering most trips backpackers would tackle. Temperature ratings can vary from one manufacturer to another because they may use different testing methods. There is also significant person-to-person variation in comfort levels.

In general, women tend to sleep “colder” than men, and require a bag with a lower temperature rating to be warm. Of course, this is also variable from person-to-person, but our experience has been (and most professionals agree) that the 20-30F rating is a good temperature rating for most people.

Lightweight

We aimed for a target of under 2 lb. With a backpacking focus in mind, keeping the weight minimal is ideal. With today’s lightweight fabrics and high lofting down sleeping bags, many bags meet this minimum requirement. 

There are plenty of quality camping and backpacking sleeping bags that weigh more than 2 lbs by brands like Kelty, The North Face, Sierra Designs, and Big Agnes. These tend to be less expensive than the ones we recommend. They also may be less compact.

Down comes from ducks and geese, often grown for meat production. The Responsible Down Standard is a voluntary certification process that ensures certain humane standards are met in producing the down, such as no live plucking or force feeding.  All of the manufacturer's included in this round up either use RDS certified down or have their own standard in place for humanelfy-raised down. If you prefer a 100% vegan option, we named the NEMO Forte 20 Endless Promise the Best Synthetic Backpacking Sleeping Bag, and included the REI Zephyr 25 Recycled Sleeping Bag to our Honorable Mentions list. Another excellent synthetic bag the ExPed DeepSleep, is light enough to double as both a camping sleeping bag or backpacking sleeping bag and is quite affordable.

Quality And Durability

Sleeping bags are a significant investment and when cared for, can and should last many years, even with heavy use. We looked for bags with quality construction and durable materials that will stand the test of time.

Shell Denier 

Shell denier (D) refers to the thickness of the outer material of a sleeping bag. Higher numbers refer to thicker shells. The biggest impact this has is in durability, so if your sleeping bag will be exposed to the elements a lot, be crawled on by a furry friend (hopefully a pet), or otherwise take a beating, a higher shell denier may be a good option. Otherwise, smaller shell deniers are a good way to shave weight.

Sleeping Bag Dimensions

Not all sleeping bags are tailored to a person’s height. While most brands offer “regular” and “tall” options, those lengths are not necessarily consistent from brand to brand. Additionally, different sleeping bags offer different measurements for shoulders and hips. Depending on your height and shape, some bags will work better than others, so you’ll want to consider that when deciding.  

Limited Down Leakage

Several factors impact how likely feathers will escape through micro-holes in your sleeping bag’s fabric. Some shell fabrics are more puncture-resistant than others. This is impacted by 1) how tightly the fabric is woven together; 2) any coatings on the fabric.

Down quality can also impact how likely micro-feathers may escape. Quality of down is related to the down-to-feather ratio. Down is less common than feathers, so a mix that has more feathers is less expensive.

The quality of the how the down is processed can also impact how likely you’ll wake up to escaped puff. Leftover quill shafts and quill points can pop through the fabric. Higher quality down has fewer of these pointy down-parts that can sneak through the fabric.

Down leakage is most noticeable in lower quality bags. All of the bags that we recommend have minimal down leakage.

Cost

Cost was not a primary consideration in this roundup, because, as mentioned above, this is the one item in your kit you don’t want to skimp on.

Customer Service And Manufacturing

With such a huge investment as a sleeping bag, it’s important to know the manufacturer stands behind its product and provides excellent customer service.  We also appreciate the opportunity to buy made in the USA products when feasible.  In the case of sleeping bags, we are lucky that several great brands make their bags here.

Ethical Down

Down comes from ducks and geese, often grown for meat production. The Responsible Down Standard is a voluntary certification process that ensures certain humane standards are met in producing the down, such as no live plucking or force feeding.  All of the manufacturer's included in this round up either use RDS certified down or have their own standard in place for humanely-raised down. If you prefer a 100% vegan option, we named the NEMO Forte 30 the Best Synthetic Backpacking Sleeping Bag, and included the REI Zephyr 25 Recycled Sleeping Bag to our Honorable Mentions list.

Packability

Packability refers to how small the sleeping bag will pack down when compressed. For backpacking adventures, it’s nice to have a sleeping bag that packs down small to help save room.


Types Of Insulation

Treeline Review writer Kate Hoch airing out her Feathered Friends Egret sleeping bag on a winter trip to climb Mt. Baker.

Treeline Review writer Kate Hoch airing out her Feathered Friends Egret sleeping bag on a winter trip to climb Mt. Baker.

Down vs. synthetic. Down is the warmest insulation available for its weight. Synthetic materials have improved significantly but still don't match down in warmth, weight, or compressibility. Down costs more, but a quality bag taken care of properly will last decades. If you prefer a vegan option, we named the NEMO Forte 20 Endless Promise our best synthetic pick. You can read more about down insulation in our Best Down Jackets guide.

Fill power. Fill power measures down quality: one ounce of 950-fill down takes up 950 cubic inches of space. Higher fill power means less down is needed to achieve the same warmth, resulting in a lighter bag. Fill power alone doesn't determine warmth though — fill weight matters too. A bag can be warm using lower fill power down if it simply uses more of it, at the cost of extra weight.

Fill weight. Fill weight is the total weight of the down in the bag. Combined with fill power, it determines how warm the bag will be.


Hydrophobic Down And Water-Resistant Fabrics

Two hikers in sleeping bags watching sunset on Mt. Whitney

Treeline Review writer Amanda Jameson documents watching the sunset on Mt. Whitney from the warmth of a sleeping bag. Photo by Amanda Jameson.

There's genuine debate in the industry over whether water-resistant down treatments are worth it. Both Western Mountaineering, one of the most respected sleeping bag makers, doesn't use hydrophobic down, citing limited long-term performance data and concerns about coating causing down to clump over time. You can read their reasoning directly: Western Mountaineering's statement.

As time goes on, water-resistant down has improved and we’re increasingly seeing the data that it works.

Most of the bags we recommend don't use water-resistant down, but many brands offer water-resistant options if you want them. With a good dry bag and proper care, an untreated down bag will perform well even in wet conditions.


What Does The Down Industry Do To Ensure Sustainable And Humane Practices?

close up of down stuffing

The global poultry industry is highly regulated. Although the Responsible Down Standard is the best way to ensure that your feathers, according to the International Down and Feather Bureau, less than one percent of their own industry uses practices that are not supported by the industry. Producers of down and feathers must sign animal welfare laws in their country to join industry organizations, even if they aren’t signed onto the voluntary Responsible Down Standard. 

Responsible down

All of the bags in this guide use down from manufacturers that either hold Responsible Down Standard certification or have equivalent animal welfare programs in place. RDS is the highest level of certification for down sourcing, ensuring no live-plucking or force-feeding. Many bags come with a QR code or hangtag that lets you trace the supply chain of your specific bag back to the source.


How To Choose A Sleeping Bag For Backpacking

Treeline Review founder Liz Thomas is using the men’s Feathered Friends Swallow 20F on a backpacking trip on the Pacific Crest Trail.

Treeline Review founder Liz Thomas is using the men’s Feathered Friends Swallow 20F on a backpacking trip on the Pacific Crest Trail.

When considering a bag, finding one that is sized to fit you and matches your warmth needs are the most important considerations. Whichever sleeping bag model you choose, you should consider these criteria to a long-lasting bag that will serve you for years.

How Tall Are You?

Unless you’re exactly 5’6” or 6’0” or 6’6”, picking the proper length sleeping bag requires most users to make a decision based on their priorities.

A bag listed as 6’0” will accommodate a user up to 6’0”. But what if you’re 6’1”? Can you squeeze into the 6’0” bag? Maybe, but your feet may bottom out in the bag, compressing the down there and thereby losing some warmth capacity. On the other hand, if you size up to the 6’6” bag, you’ve got 5” of dead space at your feet that you need to warm up, which is also inefficient (plus, it’s extra weight to carry and a bigger price tag for a bigger bag).

Sizing a bag is a balancing act.  Try to pick the bag closest to your height without going under. If you have too much room, you can always stuff some extra clothing into the bottom of your bag to take up the extra space on the nights where you find you’re cold.

How Much Width Do You Want?

There is significant variation in shoulder, hip and feet girth among sleeping bags. Like length, it’s important to find a bag that fits you well. You definitely don’t want the bag too tight. Not only will it feel uncomfortable, but if your body is pushing the dimensions of the bag, the down won’t be able to fully loft and you’ll lose much of its insulation potential, leaving you cold.

If you order online, spend a night in your bag at home. We recommend trying sleeping bags at home before taking them outdoors. Keep the tags on and you’ll still be able to return it if it doesn’t work out. We suggest ordering online because many of the sleeping bag models we recommend aren’t available in conventional outdoor stores to “try on” before purchase. But if possible, get to a store and try out other companies’ sleeping bags to get a comparative sense of what length, shoulder and hip girth fits you best.

What Will The Temperature Conditions Be?

Are you a warm sleeper or a cold sleeper? Typically, men tend to sleep warmer than women, but there is wide person-to-person variation. If you know you’re a warmer sleeper, you might be able to get away with a higher temperature rated bag than someone who sleeps colder. Also look for features such as extra down in the footbox if you are prone to cold feet.

Other factors affect your warmth when sleeping, such as water and food intake. Stay well hydrated and eat a calorie dense meal before bed and you’ll stay warmer sleeping. We also recommend wearing a hat and socks on chillier nights. Also, be sure to use a good insulating sleeping pad (see our Best Sleeping Pads guide for recommendations), or you’ll be cold no matter what bag you choose.

Want to learn more about how sleeping bag temperature ratings are determined? See our section on How are Sleeping Bag Temperature Ratings Measured?

Do You Want A Mummy Bag Or A Rectangular Bag

You'll find the vast majority of bags are either a mummy sleeping bag or rectangular sleeping bag. Backpacking sleeping bags are mummy bags for three reasons: they are lighter, compress smaller, and are more heat efficient. A rectangular bag is best for car camping.

Do You Need A Sleeping Bag Liner?

You can expand the temperature range of your bag by using a sleeping bag liner. For example, Sea to Summit claims that their Thermolite Reactor will add up to 25F to the temperature rating of your bag and potentially turn your 3-season bag into a winter sleeping bag (it can also be used as a standalone summer sleeping bag). It's also great to have a liner if unexpected cold weather pops up on an extended backpacking trip. But at 14 ounces, it will also add significant weight to your backpacking kit. Bonus — the liner will help keep your bag cleaner.

How Will You Store Your Sleeping Bag? 

One of the great things about all the sleeping bags we considered is their compressibility and how small they pack down in your backpack. However, when you’re not using the bag, it’s important to store it uncompressed for the down to retain its ability to loft. Most manufacturers include a large cotton storage sack to keep the bag in when not in use. This is a good storage option.

If you have the space, store the bag hanging in a closet, which allows full loft. However you choose to store your bag, be sure to keep it safely out of reach of pets - kitty claws are very attracted to down bags!


How To Wash A Down Sleeping Bag

When using your bag outdoors, take care to minimize dirt buildup. One way is by using a groundsheet (aka, footprint) under your sleeping bag and sleeping pad whenever you’re sleeping without a tent (aka, cowboy camping).

Many folks prefer to wear clean(ish) clothing while in their sleeping bag to minimize the dirt and smell transfer. We often wear a lightweight base layer as sleep clothes.

Even with great care, at some point, you probably will want to wash your sleeping bag. Follow the manufacturer’s instructions, but the process is generally this: wash your bag in a front load washing machine (no agitators) on the gentle cycle and only use soap specifically formulated for down (Nikwax Down Wash). Regular laundry detergent will strip the down of its natural oils and reduce its ability to loft. Use at least one extra rinse cycle to ensure all soap is washed out. Dry in a large commercial dryer on low heat with some tennis balls thrown in to help break up the clumps of down as they dry.

This is a detailed step-by-step article on how to wash a down sleeping bag. See our similar article on How to Clean and Repair Down Jackets—the steps are very similar.


Tips For Staying Warm

Some nights are simply colder than you plan for. We polled our testers and gathered some advice for staying warm on those abnormally or un-planned for cold nights. For more tips, see our entire article dedicated on How to Stay Warm While Backpacking.

  • “Eat a big hot meal with a lot of fat in it right before going to sleep. Food is fuel and fuel is warmth!” -Liz “Snorkel” Thomas

  • “Carry an inflatable pillow so you can wear all the rest of your clothes while you sleep.” -Sam Schild

  • "Layer your clothing just like you would if you were active. Start with a moisture-wicking base layer, then add increasingly heavier layers if you're cold. Add them one at a time so you don't overheat and sweat. Don't forget your hands, feet, and head, where you lose much of your heat." -Naomi Hudetz

  • “Boil water in a Nalgene and put it into your bag. Do sit-ups before bed in your bag, or add a dog to your bag for warmth.” -Sara “Socks” Kruglinski


Treeline Review writer Amanda Jameson captures in a photo the importance of having a warm sleeping bag when watching sunrise on Mt. Whitney. Photo by Amanda Jameson.

Treeline Review writer Amanda Jameson captures in a photo the importance of having a warm sleeping bag when watching sunrise on Mt. Whitney. Photo by Amanda Jameson.

How We Tested

A pile of sleeping bags

To test backpacking sleeping bags, we took dozens of bags on thousands of miles of backpacking trips and thru-hikes over the past 4 years including:

In addition, we took them on countless shorter and weekend trips including mountaineering summits in the Cascades, including Mt. Baker.

To further investigate the bags, we looked at consumer reviews on REI, Backcountry, and manufacturer websites. We also considered our own personal experiences.

From the list of contenders, we narrowed down the list by considering the positives and negatives reviewers found. If a complaint came up frequently, such as the troublesome zipper of the promising-looking but now-unavailable Marmot Phase 20, the bag was knocked out of the running. We also chose to leave out bags that were very new, since we don’t have data on their performance and durability over the long term. We think a sleeping bag is a huge investment to make without years of supporting data. The bags we recommend are proven to last.

The final winners were all bags with overwhelmingly positive user experiences, with almost no complaints. The top award winners, the Feathered Friends Egret and Feathered Friends Swallow were an easy pick — they fit our criteria for warmth, weight and quality with virtually no negatives aside from price.

The other bags that won our recommendations stood out as great options for folks who need something just slightly different in terms of size (MegaLite), price (Magma), and comfort (Montbell), but still met all our primary criteria without significant negatives.

OUR TESTING PROCESS
Purchased and tested 17 sleeping bags over thousands of trail miles across the Sierra Nevada, Rocky Mountains, and Pacific Northwest, covering down, synthetic, ultralight, and wide options across multiple seasons.
9
Top Picks
17
Bags Tested
4+
Years of Testing
3
Regions Tested In
🏕️ How We Tested
  • Multi-night backpacking in the Sierra Nevada
  • Rocky Mountains & Pacific Northwest
  • Cold, shoulder-season & warm weather trips
  • Tested by warm & cold sleepers
  • Side-by-side comparisons on same trips
📋 What We Evaluated
  • Temperature rating accuracy
  • Warmth-to-weight ratio
  • Packability & loft retention
  • Hood fit & draft collar design
  • Comfort for different sleep styles & body types
🏔️
High Sierra
❄️
Cold & Shoulder Season
🌲
Pacific Northwest
🎒
Thru-Hiking

Kate Hoch is a thru-hiker, mountaineer, and huckleberry enthusiast.

Kate Hoch is a thru-hiker, mountaineer, and huckleberry enthusiast. Photo by Dan Slattery.

About the Author / Why You Should Trust Us

By trade, I’m a mechanical engineer designing and building machines to test the reliability and safety of fitness equipment. I’ve put this engineer’s mindset to work when refining my backpacking gear choices over the years, honing in on details, learning about the nuances of material and design choices. 

When I’ve been unable to find what I want in gear, I’ve embraced MYOG (Make Your Own Gear), either modifying existing gear to include features I want, or in the case of my current long distance backpack, taking my favorite elements of several different packs, and combining them into my dream pack built from scratch.

When asked about what I’m good at, one of my go-to answers is sleeping. I’m someone who’s always needed a good solid 8+ hour block of sleep to be able to function, so when I started backpacking ~2007, it was imperative that I find a comfortable way to sleep in the backcountry. In my 8,000+ miles of backpacking, including the entire Pacific Crest Trail, Continental Divide Trail, Hayduke Trail, and Sierra High Route, and multiple ascents of Cascade Volcanoes including Mt. Hood and Rainier, I’ve had the time and variety of conditions to refine my sleep system to perfection.

I’ve been on the executive board of ALDHA-West (American Long Distance Hiking Association - West) for the past 4 years. As part of our five annual pre-backpacking season educational events (called “Rucks”), I’ve conducted many pack shakedowns and been a panelist on lightweight gear forums. I’ve shared my knowledge and expertise with hundreds of new backpackers. Running these events also keeps me on top of the newest available options for all kinds of backpacking gear.

See all articles by Kate on her author page.