The Best Backpacking Sleeping Bags of 2018

The Best Backpacking sleeping bag review

If you're looking for a new backpacking sleeping bag, you've come to the right place! We researched over 80 possible options, taking the top 16 out in the field, and directly comparing them via a rigorous testing regimen. Our primary field testing composed of backpacking trips through the North Cascades and the Sierra, where we traveled through various climates and conditions to assess their temperature regulation and versatility. We weighed them ourselves and measured their packed volume to give you the best resources to make an informed decision on each model's weight and size and how they compared to one another. Whether you're looking for solid overall performance, a miniscule packed volume, a budget pick, or the best models for those who like to sleep on their stomachs, we have some great recommendations for you.

Read the full review below >

Test Results and Ratings

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Analysis and Award Winners


Review by:
Ian Nicholson
Review Editor
OutdoorGearLab

Last Updated:
Monday
May 14, 2018

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May 2018
The summer backpacking season is right around the corner, so we've updated our review to include a handful of new options, including the new ultra spacious NEMO Disco 30, the insanely light Western Mountaineering SummerLite, and the solid all-arounder Mountain Hardwear Phantom Spark. This review focuses primarily on sleeping bags geared towards backpacking, and many of these models are also great for car camping or summertime mountaineering. We have a variety of Top Pick and Best Buy recommendations below for various niche needs, and of course, check out our best overall recommendation, the Western Mountaineering MegaLite, which continues to dominate the field. Once again, the Megalite won our Editors' Choice award for its solid low weight, packed size, and spacious dimensions. We also have a comprehensive women's-specific Sleeping Bag Review.

Best Overall Model


Western Mountaineering MegaLite


Western Mountaineering Megalite 30
Editors' Choice Award

$450.00
at Amazon
See It

Weight: 1.5 lbs | Fill Power: 850+ Goose Down
Spacious and comfortable cut
Lightweight
Compressible
Made in the USA
Versatile
Best feeling fabric in our review
Stuff sack doesn't compress well
Expensive

If we could only have one sleeping bag for backpacking and 3-season camping, it would be the Western Mountaineering MegaLite. The MegaLite has awesome across the board performance. It is one of the lightest and most compressible models in our review (and on the market) but is still roomy enough to feel comfortable when car camping or for most side and tummy sleepers to enjoy on extended outings while deep in the backcountry. The materials its constructed with feel the best against our skin and are among the lightest in our review. All these attributes combined to make it one of the most versatile models and our testers' favorite choice for most applications.

You can buy a lighter or a more comfortable bag but not much lighter or much more spacious; and, no other model combines these two performance characteristics as well. The MegaLite is just a solid all-around performer. One of its only downsides is the price; at $450, it's one of the more expensive models in our review, but for the price, you get a bag that is made in the USA that will last two decades of or more of use with just standard care. While there are many great backpacking sleeping bags out there, the MegaLite is the best of the best.

Read review: Western Mountaineering MegaLite

Best Light and Compressible


Marmot Phase 20


Marmot Phase 20
Top Pick Award

$367.16
at Amazon
See It

Weight: 1.44 lbs | Fill Power: 850+ Fill Power Goose Down
Extremely lightweight
Very compressible
Silky internal fabric
Highly versatile
Side zipper catches
Expensive

When Marmot recently updated their sleeping bag line with the new Phase series, they certainly didn't pull any punches anywhere quality was a concern. This new line easily is one of the nicest sleeping bag lines currently on the market. Both the Marmot Phase 20 and Phase 30 (see below) are top-notch models. The Phase has top-quality 850+ down fill and some of the lightest weight shell fabrics you can find. This combination equates to one of the lightest and most compressible bags (for their warmth) currently available. A bonus is that the bag has an exceptionally well-designed hood and sports some of silkiest feeling internal fabrics we've tested.

The Phase topped our rating metrics in almost every category, and was just a hair below our Editors' Choice winner. The only (tiny) thing is our review team didn't care too much for was the zipper, which is small and easily one of the most prone to catching. The shoulder and hip girths (60" and 59" respectively) are in line with other performance-oriented mummy bags. It's also on the expensive end of the spectrum, but it sure does deliver for the price, and it's the lightest 20F-rated model in our review.

Read review: Marmot Phase 20

Best Bang for the Buck


REI Co-op Igneo 25


REI Igneo
Best Buy Award

$270 List
List Price
See It

Weight: 1.63 lbs | Fill Power: Water-repellent 700-fill duck down
Fairly light and compact
Solid quality for the price
Descent hood design
Versatile
Average warmth
Not super warm for its temperature rating
Tight around the legs

The REI Co-op Igneo 25 wins our overall "Best Value" award, as it offers the best overall performance for the price. It's a superb balance of quality, fairly low weight, solid compressibility, and performance for a pretty unbeatable price. The Igneo isn't the cheapest option around (the $150 Kelty Cosmic Down wins in that category), but for $270, the Igneo checks in close to the performance of most high-end bag but at half the price.

The only thing worth noting is our testers didn't find the Igneo lived up to its stated temperature rating. While it felt warmer than most 30F, the 25F rating is pushing it. The 60" shoulder width is about average, tapering to 55" at the hips, and the legs felt unnecessarily tight. We did love some of the little features though, like the durable shell and non-snagging zipper. Overall, this is a stand-out backpacking sleeping bag, with solid materials, specs, packed size, and a respectable 700 down-fill, all for an excellent price.

Read review: REI Co-op Igneo 25

Best Buy on a Tight Budget


Kelty Cosmic Down 20


Kelty Cosmic Down 20
Best Buy Award

$149.95
at Amazon
See It

Weight: 2.81 lbs | Fill Power: 600 Fill
Affordable
Great value bag
Inexpensive
Light and compact for its price range
Heavy
Not super warm
Too roomy

The affordable, yet reasonably light and compressible Kelty Cosmic Down 20, also won our Best Buy award for those on a tight budget. While hardly an overall top performer, this is the best down bag we've ever seen for $150. This bag is far more durable and compressible than it's similarly priced synthetic insulated counterparts and offers beginning or budget-conscious backpackers an exceptional value.

It's about a pound heavier than other 20-degree bags in our review, so you'll have to ask yourself what's more important: a one pound weight savings on the trail, or $300 more dollars in your wallet? And even though it's rated to 20F, it wasn't that warm, so if you are a cold sleeper or usually camp in lower temperatures, you'll want something warmer; for most backpackers, it is more than adequate. Otherwise, everyone on a budget should consider the Cosmic Down 20 (and pocket the savings). If you are backpacking in warm summer conditions and want to shave a few more ounces, check out the Kelty Cosmic Down 40 as well.

Read review: Kelty Cosmic Down 20

Top Pick for Wet Conditions


The North Face Hyper Cat 20


The North Face Hyper Cat 20
Top Pick Award

$240 List
List Price
See It

Weight: 1.88 lbs | Fill Power: Synthetic "Heatseeker"
Small packed size
Light for a synthetic bag
Center half-zipper
Cozy interior fabric
Synthetic insulation isn't super long lasting
Lower warmth

The North Face Hyper Cat 20 is our Top Pick for Wet Conditions. During our water saturation testing, the Hyper Cat, like other synthetic-fill bags, dried in roughly 20% of the time as treated water-resistant down, making it a much more ideal bag for wet conditions. However, what truly sets the Hyper Cat apart from most other synthetic bags is how incredibly small it packs down and how lightweight it is for its temperature rating (1 lb 14 oz). It's lighter and more compressible than several down bags we tested, and it even has roomier than average dimensions. All of our testers loved its half-length center zipper that still allowed plenty of ventilation on warm nights; it was also just plain easier to use.

This wasn't a particularly warm-for-the-rating bag, and there is noticeably less insulation in the legs than in other models. That's fine though if you always use a pad underneath you, and it's probably how it achieves some of the additional weight savings and compressibility compared to other synthetic models. If you're looking for a synthetic bag, whether for wet conditions, animal rights concerns, or you have allergies to down and want one of the highest performing synthetic bags out there, the Hyper Cat is your bag. It is worth noting that the Mountain Hardwear HyperLamina Spark 35 is another fantastic option that, while not as warm, is more packable and slightly lighter (1 lb 12 oz).

Read review: The North Face Hyper Cat 20

Top Pick for Cold Temperatures (AKA Best 20F model)


Western Mountaineering UltraLite


Western Mountaineering UltraLite
Top Pick Award

$500.00
at Amazon
See It

Weight: 1.81 lbs | Fill Power: 850+ Goose Down
Warmest bag in our review
Very lightweight
Great no-catch zipper design
Excellent compressed size
Expensive
Very warm for mid-summer
Weak velcro closure on draft collar
Slightly tight dimensionally

The Western Mountaineering UltraLite is an extremely toasty bag. By far the warmest model in our review, it was noticeably toastier than the other contenders we tested with a 20F rating. Even more impressive is that, despite being warmer than other similarly rated models, it was incredibly lightweight and compressible. It packs down pretty small in its stuff sack, but we were able to get it a third smaller with a good compression bag.

In fact, it was so warm that you might find it too much for mid-summer backpacking. It's also cut a little narrow (59" shoulders and 51" hips), making it a little less comfortable than a roomier bag. But, if you get cold easily, or plan to adventure in colder than average conditions, the Western Mountaineering UltraLite is tough to beat.

Read review: Western Mountaineering Ultralite

Top Pick for Light and Fast Backpacking and Mountaineering


Marmot Phase 30


Top Pick Award

$319.16
at Amazon
See It

Weight: 1.1 lbs | Fill Power: 850 Fill Power Down with Down Defender
Lightweight
Smallest packed size in our review
Nice interior fabric
Accommodates light down jackets
Slightly tight internal dimensions
Expensive

If you're on a trip where weight and pack space are your highest priority, but you need or want something more significant than an ultralight quilt, the Marmot Phase 30 is hard to beat. It weighs only 1.1 pounds, and compresses down to almost the size of a Nalgene, making it the lightest and most compressible model we tested. It's a half to a full pound lighter than most bags with a similar temperature rating.

While it's warm enough for most backpackers and summertime mountaineering, it isn't a toasty 30°F bag. With that in mind, if you get cold easily or embark on outings with overnight temperatures regularly below 30-35°F, we'd recommend the Western Mountaineering SummerLite which is only an ounce heavier but warmer despite its 32F rating.

Read review: Marmot Phase 30

Top Pick Favorite 30°-35°F model


Western Mountaineering SummerLite 32


Western Mountaineering SummerLite 32
Top Pick Award

$390.00
at Amazon
See It

Weight: 1.15 lbs | Fill Power: 850+ Goose Down
Super lightweight
Very light for its warmth
As warm, or warmer than many other 30° F models
Extremely compressible
Best feeling interior fabric
Made in the USA
Zipper snags less frequently than other ultralight models
Expensive
Tighter-than-average dimensionally even among performance-oriented models.

The Western Mountaineering SummerLite is perfect for any backcountry adventure where pack space and every ounce carried is at a premium. This model is designed to be as warm, light, and as compressible as possible without sacrificing any basic functionality but certainly won't win many buyers in the comfort-first crowd. It is among the very lightest models in our review but remains reliably warm.

It achieves this by offering slim, thermally efficient dimensions, and is constructed with some of the nicest fabrics and the highest quality 850+ goose down available. It's also 100% Sewn in San Jose, California. For more casual all-around applications this bag is okay, but for long-range missions or summer alpine climbing where every ounce matters this bags warmth to weight ratio is tough to beat.

Read review: Western Mountaineering SummerLite

Top Pick for Exceptional Comfort


Sierra Designs Backcountry Bed 700


Top Pick Award

$249.95
at Amazon
See It


Weight: 1.93 lbs | Fill Power: 700 Fill Power PFC-Free Dridown
Incredibly comfortable
Ideal for side and tummy sleepers
Excellent price for a down bag
Surprisingly low weight (sub-two pounds)
The non-traditional design is not for everyone
Inefficient stuff sack

The 3-season Sierra Designs Backcountry Bed 700 bag has a unique design, creating one of the more comfortable and bed-like feels of any sleeping bag we have ever tested. This 35-degree contender does not have any zippers or Velcro flaps; instead, it has a huge U-shaped opening covered by a down flap, which acts as a quilt. This quilt/flap is a cozy way to close your bag, and it helps regulate temperature well, particularly on warmer nights. The best part is the unmatched freedom of movement for your upper extremities, making tummy or side sleepers, who may tuck their arms under a pillow or jacket, about as comfy as possible. There's also a lower opening for your feet, so if they need to "breathe" at night for you to sleep well, you can pop them out of the bag with ease. It also has a sleeve for your sleeping pad, which helps keep you on your pad if you toss and turn a lot. This bag has so many features that it's hard to list them all.

On the downside, it's not a very warm bag. While it worked well at its 35F rating, on colder nights you'll want something warmer. It weighs just under 2 pounds, which is excellent, but not that light for a 35F bag. Finally, this bag doesn't compact that well. These points might all be mute if you dread "sleeping" in a sleeping bag. The Backcountry Bed gives you the feeling of home on the trail, and we loved how comfortable it was.

Read review: Sierra Designs Backcountry Bed 700

Notable for Tummy and Side Sleepers


Nemo Disco 30


Nemo Disco 30

$259.95
at Amazon
See It


Weight: 2.4 lbs | Fill Power: 650 Fill Power Nikwax
Incredibly comfortable
Ideal for side and tummy sleepers
Spacious interior dimensions
Features our review team's favorite water-resistant down
Non-traditional design is not for everyone
Slightly larger-than-average packed volume
You can buy a lighter weight bag for the price
Included stuff sack is large and doesn't compress the bag very well

The NEMO Disco 30 is one of our favorite models currently available that is geared towards comfort but is still light and functional enough to take into the backcountry. The Disco 30 is easily one of the most comfortable backpacking sleeping bags on the market and is a notable for tummy, side, and high knee sleepers.

The Disco's unique hour-glass shaped variation on a traditional semi-rectangular design coupled with roomy dimensions allowed for the most unencumbered movement of its occupants lower extremities. We also loved that the Disco still checks in at a relatively respectable weight; while it wasn't quite as light as the Backcountry Bed, it was warmer and lived up to its 30°F temperature rating - something other roomy bags often fall short on.

Notable for 25°-30°F Model


Mountain Hardwear Phantom Spark 28


Mountain Hardwear Phantom Spark

$399.00
at Amazon
See It

Weight: 1.43 lbs | Fill Power: 800+ Goose Down
Warmer than any 30°F model and several 25°F models
Very light for its warmth
Lighter than most 30°F models
Excellent compressed size
Cozy interior fabric
Expensive
Tighter-than-average internal dimensions
Slightly tight dimensionally

The Mountain Hardwear Phantom Spark 28 is quite the fireball of three season bag, and our testers found it closer in warmth to most 25F rated models than most 30F. What impressed us further was despite how warm the Phantom Spark is, it provided remarkably low weight and a minimal compressed volume, outperforming many of those same 30F models.

The Phantom Spark archives this impressive warmth to weight ratio with a slim, thermally efficient dimensions, high quality down fill, and a review thin 10D shell. Despite the thin shell as long as regular care was taken, you could expect a few decades or more of use out of this notably solid all-around bag.

Read review: Mountain Hardwear Phantom Spark 28

select up to 5 products
Score Product Price Our Take
95
$460
Editors' Choice Award
If you're looking for one bag to do it all, this is it.
94
$459
Top Pick Award
Warm, compressible, and lightweight, this is our Top Pick for a light and cozy design.
91
$500
Top Pick Award
The warmest 20F bag in our test, this model also shines in weight and compressibility.
90
$420
Top Pick Award
One of the lightest and most compressible models in our review, this bag doesn't give up much for its temperature rating.
90
$400
One of the better warmth to weight ratios in our review, the Phantom Spark doesn't cut any corners when it comes to design, fill quality, or materials.
88
$399
Top Pick Award
The Phase 30 was our Top Pick for Low Weight; while it certainly isn't the warmest 30° bag out there, it's close, and is a pound lighter than its closest competition.
88
$469
A high-performer in weight and packed volume, this model is for minimalists.
88
$250
Top Pick Award
If you want the lightest and most compressible sleeping bag for backcounty outings but struggle with the sometimes claustrophobic feel of traditional mummy bags, the Backcountry Bed 700 should be on your radar.
85
$400
Top-of-the-line materials and high performance make this bag a good choice across the board.
84
$260
If you are someone who struggles to sleep in the backcountry, specifically a tummy or side sleeper, this model allows you to sleep in the position you are more familiar with.
81
$240
Top Pick Award
Compressible and lightweight, this bag offers the best in these metrics for a synthetic 20F bag.
81
$270
Best Buy Award
Close in weight and packed size to many more expensive bags, this model is a good, inexpensive option.
78
$169
While it isn't the highest performer, this model is still a good option for a do-it-all bag.
78
$220
A 35F synthetic bag that barely tips the scales, this model is the lightest in its class.
74
$160
Best Buy Award
If you're looking to save cash and want a bag that lasts, this is a good option.
65
$90
With a price tag under $100, this model is the best choice for an inexpensive 20F bag.

Analysis and Test Results


Your sleeping bag is likely the most important insulating layer that is carried on any overnight wilderness excursion and likely provides the best warmth-to-weight ratio of anything in your pack. Most importantly, except for shelters, sleeping bags have more impact on pack weight and available space than almost any other piece of gear or clothing in your pack.

If on a budget  try not to skimp too much on quality - look for a bag that suits your needs  and balances warmth  weight  and versatility. If possible  consider two bags  a lower priced sleeping bag for car camping and a lightweight option for backpacking and mountaineering. Photo: Sunrise on Mt. Baker  Shannon Ridge  North Cascades  Washington.
If on a budget, try not to skimp too much on quality - look for a bag that suits your needs, and balances warmth, weight, and versatility. If possible, consider two bags, a lower priced sleeping bag for car camping and a lightweight option for backpacking and mountaineering. Photo: Sunrise on Mt. Baker, Shannon Ridge, North Cascades, Washington.

Investing in a quality backpacking sleeping bag that is suited to your needs has a significant impact on how good a night's rest you get and subsequent, your backcountry adventure. Besides backpacking and mountaineering, sleeping bags are also the bed of choice for car campers, travelers, and couch surfers.

One of the most important factors when purchasing a sleeping bag is insulation type  as it has the biggest impact on the overall performance characteristics of a sleeping bag.
One of the most important factors when purchasing a sleeping bag is insulation type, as it has the biggest impact on the overall performance characteristics of a sleeping bag.

We rated each bag on its warmth, weight, packed size, features, and versatility. We packed and unpacked them, zipped and unzipped them, and of course, slept in all of them to evaluate their comfort, assess their dimensions, and compare any other features they may have. You can read our comparisons of each testing metric below. This year, we've updated our existing review to include several new, and innovative models and compared them to previous award winners.

Warmth is an important factor when buying a sleeping bag. All the bags we tested were rated to between 20°-35°  with most of them being closer to 30° F.
Warmth is an important factor when buying a sleeping bag. All the bags we tested were rated to between 20°-35°, with most of them being closer to 30° F.

Value


If you're on a budget, check out the table below. It shows you each model's overall score (on the X-axis), versus its retail price (on the Y-axis). Not surprisingly, there's a gradual upward curve, where score tends to increase with price. (This isn't always the case - we often come across overly-expensive outdoor items that don't live up to the hype, or price tag. Conversely, sometimes a "budget" pick works just as well as a more expensive counterpart.) With backpacking sleeping bags, a higher price tag usually comes from a higher-quality fill and lighter materials, which all drive up the cost. When looking for a good value pick check out the bags that lie to the right of the graph (higher score), but towards the bottom (lower price). This includes models like the Sierra Designs Backcountry Bed 700 ($250) and the REI Co-op Igneo 25 ($270), which won our Best Buy award.


Warmth


Warmth is more-or-less directly related to the amount of loft (AKA insulation) a bag has, measured in the thickness of the insulation between you and the external environment. Except for loose fitting bags, which are far less thermally efficient, more volume of insulation (not necessarily weight) equals more warmth in the majority of cases.


Fit or the cut of the bag is the next most important factor in determining warmth. Models that are too tight or too short won't allow the insulation to loft up correctly, and as a result, you may feel colder when pressed against specific areas. More importantly, if a bag is too large or its dimensions are too roomy, it will take longer for your body heat to warm all the drafty dead air spaces. Conversely, depending on the external temperature your body heat will be spread to thin (and you'll feel cold) with a wide cut, thermally inefficient bag even though on paper it might have more insulation than a narrower cut model.

The WM MegaLite features 13 ounces of high quality 850+ fill and was one of the warmest 30F bags we tested.
The WM MegaLite features 13 ounces of high quality 850+ fill and was one of the warmest 30F bags we tested.

Some bags tested in this review, such as the Western Mountaineering UltraLite and SummerLite, have tighter interior dimensions, resulting in slimmer feeling cuts. Not to fear, most broad-shouldered folks can still at least wear a lightweight jacket while sleeping inside these bags. The rest of the bags we reviewed are wider dimensionally speaking, and a majority of people could wear a mid-weight jacket (or two) to boost insulation on colder nights. It's worth noting that Western Mountaineering sleeping bags are available in multiple lengths and widths, which is a huge advantage because you can get a bag that fits your body well. Look at the foot, hip, and shoulder circumference to compare dimensions for unisex bags. We've included these measurements in the specification tables found in each review when available from the manufacturers.

Shown here are the European ratings  which are printed on the inside of a sleeping bag. These ratings are slightly more objective than the typical US ratings but do have some inconsistencies. In theory  the EN lower limit is a rating for men and the EN Comfort Rating is a rating for women.
Shown here are the European ratings, which are printed on the inside of a sleeping bag. These ratings are slightly more objective than the typical US ratings but do have some inconsistencies. In theory, the EN lower limit is a rating for men and the EN Comfort Rating is a rating for women.

The warmest contenders for their respective temperature rating were the high-quality down bags from Western Mountaineering, notably the MegaLite, and SummerLite and Ultralite. The Marmot Phase 20 followed closely behind the models mentioned above. All of these bags have 850+ fill power down and plenty of it.

The Phase 20 was easily one of the warmest 20° F bags we tested. The only model that was warmer was the Western Mountaineering Ultralite  though it's worth noting that the difference in warmth between these two bags was minimal. The Phase is slightly lighter and more compressible.
The Phase 20 was easily one of the warmest 20° F bags we tested. The only model that was warmer was the Western Mountaineering Ultralite, though it's worth noting that the difference in warmth between these two bags was minimal. The Phase is slightly lighter and more compressible.

The least warm bags based on their given temperature ratings were the Marmot Phase 30, the Mountain Hardwear HyperLamina Spark 35 and the Patagonia 850 Down 30. The thinner insulation and sewn through the design of the Patagonia 850 offers less protection from the elements. The lack of a draft tube allows more cold air inside the bag, leaving it less toasty than others. That said, both of these models will be excellent options when sleeping at 40°F and above.

To provide a better review during our testing phase  we performed several directly side-by-side tests. We compared each bag's warmth in relation to other bags of similar ratings. We also analyzed and contrasted each model's EU ratings  quality and volume of fill  and dimensions.
To provide a better review during our testing phase, we performed several directly side-by-side tests. We compared each bag's warmth in relation to other bags of similar ratings. We also analyzed and contrasted each model's EU ratings, quality and volume of fill, and dimensions.

It's worth noting that warmth is also heavily influenced by conductive heat loss to the ground. Choosing an appropriate sleeping pad is essential, especially in colder conditions or when sleeping on snow. Our Best Sleeping Pad Review will point you in the right direction for a warm, comfortable pad. Choosing the right backpacking tent or ultralight shelter for your trip will also influence the perceived warmth of a sleeping bag. OutdoorGearLab also has an excellent Backpacking Tent Review and Ultralight Backpacking Shelter Review, where you can finish out your research on the best sleeping/shelter kit for your next trip. Keep in mind that warmth degrades over time, especially if the bag is not cared for. We recommend educating yourself on proper storage and care.

The backpacking sleeping bags in the review were tested in traditional backpacking tents, single wall tents, silk-nylon tarps, and under the open sky during open bivies above tree-line and while sleeping on exposed alpine ridges. See the Buying Advice on how standardized testing has helped (or hurt!) companies decisions on what temperature rating to give a sleeping bag. Keep in mind that EN comfort ratings are conducted in a lab and not real-world conditions. That helps explain how two bags rated 30 degrees can not have the same warmth in the real world.

In climbing and mountaineering  and perhaps even more than long-distance hiking  weight is an important factor. You may have to make challenging technical moves with the weight of your sleeping bag on your back. Photo: An open bivy with the MegaLite under the stars while climbing the North Ridge of Forbidden Peak.
In climbing and mountaineering, and perhaps even more than long-distance hiking, weight is an important factor. You may have to make challenging technical moves with the weight of your sleeping bag on your back. Photo: An open bivy with the MegaLite under the stars while climbing the North Ridge of Forbidden Peak.

Weight


The weight metric is simple as we compared how much each model weighed. Models with the same temperature rating tipped the scales differently mostly due to insulation type, amount, and quality, shell material, bag dimensions and features.


In general, heavier bags use either synthetic insulation or lower fill-power down (500-700). Many of the highest performing bags we tested use the best down (800-850+ fill-power) and lightweight, expensive shell fabrics. A bag's cut and its overall dimensions also play a major factor in the weight, as a slimmer cut bag has less overall materials, is more thermally efficient, and thus offers slightly less insulation for a given weight.

The Spark III is on the more expensive side ($440)  but if you want a 3-season bag on the warmer end of the spectrum and still want the lightest and most packable sleeping bag you can buy  this model is hard to beat.
The Spark III is on the more expensive side ($440), but if you want a 3-season bag on the warmer end of the spectrum and still want the lightest and most packable sleeping bag you can buy, this model is hard to beat.

At 1 pound 1.6 ounces, the Marmot Phase 30 is the lightest bag in our review. While it wasn't the warmest 30F bag we tested, it's suitable for most backpacking and summertime mountaineering trips. The Western Mountaineering SummerLite was only a little over an ounce heavier but was noticeably warmer (if our testers could quantify it we would call it 5F warmer) than the Phase 30. The SummerLite was able to do with by sporting slightly more insulation and slimmer internal dimensions. If you run on the cold of 30F, we'd recommend the Mountain Hardwear Phantom Spark 28, which was as warm as several of the 25F models but only weighed 1 lbs 6.5 ounces.

The Phase 30 offers a low weight and excellent compressibility. While it certainly wasn't the warmest 30F bag out there  it wasn't far off and was almost half-a-pound lighter than its closest competition. Photo: Tracey Bernstein wakes up in Red Rocks Nevada after a cold Fall night.
The Phase 30 offers a low weight and excellent compressibility. While it certainly wasn't the warmest 30F bag out there, it wasn't far off and was almost half-a-pound lighter than its closest competition. Photo: Tracey Bernstein wakes up in Red Rocks Nevada after a cold Fall night.

The Sea to Summit Spark III is crazy light for its warmth. It's no surprise the Spark III features high quality 850+ fill power down, sports the tightest cut, lightest 10D shell fabric, and the shortest (1/3 length) zipper. What is impressive is both the Marmot Phase 20 and the Western Mountaineering MegaLite are less than two ounces heavier and are still warmer. The Marmot Phase 20 is unbelievably light for its temperature rating (20F), featuring top quality 850+ down and a similar 10D shell. The MegaLite (1 lb 8 oz) offers a full-length zipper, is comparable warmth to the Spark III but is much more spacious (but still efficient) dimensions.

The longer and more ambitious your backpacking objective is  the more important spending a little extra to buy a lighter weight sleeping bag becomes. Here  two lightweight backpacking bags out for a side-by-side comparison along the John Muir Trail.
The longer and more ambitious your backpacking objective is, the more important spending a little extra to buy a lighter weight sleeping bag becomes. Here, two lightweight backpacking bags out for a side-by-side comparison along the John Muir Trail.

While the Marmot Phase 20 was light, it's worth noting that the Western Mountaineering UltraLite was warmer and one of the lightest in our review (at 1 lb 13 oz). In addition to being incredibly lightweight, all of these models also scored a 10 out of 10 for warmth.

The Phase 20 is one of the best 20°F bags on the market. While expensive  it lives up to its price point  offering top-notch materials  insulation  and design - at a very light weight.
The Phase 20 is one of the best 20°F bags on the market. While expensive, it lives up to its price point, offering top-notch materials, insulation, and design - at a very light weight.

Among synthetic bags we tested, our testers were very impressed with The North Face Hyper Cat. While it's super warm for its temperature rating, at 1 pound 14 ounces, it was warm enough to be used to 20-25°F while wearing a layer or two. It's an exceptionally light synthetic option and is a pound+ lighter than a majority of synthetic models - it was also lighter than several 30°F down bags.

Weighing sleeping bags for our OutdoorGearLab's best backpacking sleeping bag test. There was a pretty big range in weights  with some options weighing half of what other models weighed.
Weighing sleeping bags for our OutdoorGearLab's best backpacking sleeping bag test. There was a pretty big range in weights, with some options weighing half of what other models weighed.

Comfort


Comfort is a subjective category that depends on a combination of internal dimensions, a given users sleeping style, and a bags interior fabric. Increasing the size of the bag's internal dimensions (to a point) allows for a "more comfortable" bag for most, as the user has more room to move around and spread out. This trait becomes even more important for users who prefer to sleep on their sides or stomachs.

Three of the most comfortable and roomiest backpacking sleeping bags in our review. From left-to-right: the Sierra Designs Backcountry Bed 600  Nemo Salsa 30 (no longer available)  and Western Mountaineering MegaLite.
Three of the most comfortable and roomiest backpacking sleeping bags in our review. From left-to-right: the Sierra Designs Backcountry Bed 600, Nemo Salsa 30 (no longer available), and Western Mountaineering MegaLite.

How worth it is having more internal space? The answer is certainly not linear. As a bag is made larger, manufacturers will need to add more material and insulation to maintain the same warmth, with the primary disadvantage coming in weight and packability.


In addition to having the space for sprawling and thrashing, our ratings focus on which features will contribute to, or detract from comfort. Insulation type influences comfort; all of our testers agreed that sleeping in a high-quality down bag is like floating on a super light cloud while zipping into a synthetic model is fine, but no-doubt less heavenly.

Another cool feature that affects the comfort of a bag is having a single half-length zipper in the center of the bag. This design is featured on the North Face Hyper Cat (shown here) and the Patagonia Down 850 30 F sleeping bag. While this design isn't quite as functional for regulating temperature  our entire testing team loved it. In fact  cooking while still in your sleeping bag made for a great morning of hanging out and drinking coffee.
Another cool feature that affects the comfort of a bag is having a single half-length zipper in the center of the bag. This design is featured on the North Face Hyper Cat (shown here) and the Patagonia Down 850 30 F sleeping bag. While this design isn't quite as functional for regulating temperature, our entire testing team loved it. In fact, cooking while still in your sleeping bag made for a great morning of hanging out and drinking coffee.

The Sierra Designs Backcountry Bed 700 was the most comfortable bag in our review, with the semi-rectangular Nemo Disco 30 being a very close second and the Western Mountaineering MegaLite ranking third.

Tracey Bernstein taking advantage of the Backcountry Bed 700 comforter style flap while side and tummy sleeping in the Nevada desert.
Tracey Bernstein taking advantage of the Backcountry Bed 700 comforter style flap while side and tummy sleeping in the Nevada desert.

First the Sierra Designs Backcountry Bed 700, which provided our testers with the most bed-like feel of any backpacking sleeping bag we have ever seen. The Backcountry Bed doesn't have a single zipper or Velcro flap of any kind. Instead, it's designed with a large "U"-shaped opening that is covered with a down flap. This down flap acts (and feels) like a quilt. This not only helps regulate temperature exceptionally well but also offers unmatched freedom of movement in the user's upper extremities.

You can see the flap-style closure design featured in this bag. This flap acts like a comforter  letting its occupant tuck themselves in as if they were in a bed. It also allows its users to sleep in most positions comfortably but still wraps around efficiently enough to maintain a comfortable amount of warmth. This flap features two handwarmer sleeves to help keep its user warm.
You can see the flap-style closure design featured in this bag. This flap acts like a comforter, letting its occupant tuck themselves in as if they were in a bed. It also allows its users to sleep in most positions comfortably but still wraps around efficiently enough to maintain a comfortable amount of warmth. This flap features two handwarmer sleeves to help keep its user warm.

Best of all, this model weighs a respectable 1 pound 15 ounces. While we loved the Backcountry Bed 700 and founds that it offers a mega comfort-oriented design, its lower dimensions were average and not as spacious as the WM MegaLite. The inner fabric of the Backcountry Bed was also not quite as comfortable as those found on the Megalite.

The Nemo Disco replaces the old Salsa and is one of the best sleeping bags for folks who prefer to sleep on their sides or their stomach. The Disco is a semi-rectangular bag that features an hour-glass cut rather than the traditional taper of a mummy bag. This design allowed tummy-sleepers to pull their knee to mid-height comfortable. While there are many wide bags, the Disco strikes a delicate balance between comfort and weight and is still reasonable enough that most backpackers wouldn't even hesitate to carry it.

Lastly is our Editors' Choice the MegaLite. The MegaLite offers wider-than-average dimensions but what makes it unique is it's significantly lighter and more packable than the two contenders above, nearly as comfortable, and still among the lightest and most compressible of any model in our review.

The Backcountry Bed 600 3-season offers pretty unbeatable upper body movement. Its unique design allows the user to sleep in pretty much any position they desire for their upper body.
The Backcountry Bed 600 3-season offers pretty unbeatable upper body movement. Its unique design allows the user to sleep in pretty much any position they desire for their upper body.

Lastly, it's important to consider total comfort throughout a trip, not just when you're inside your sleeping bag at night. A bag that's slightly more comfortable to sleep in may be far heavier and bulkier, and therefore less comfortable to carry. Weigh both factors and keep them in mind when searching for a new bag.

Comfort is not only represented when you are inside your sleeping bag.Because you're carrying your pack most of the day  weight and packed size also play a huge role in your comfort during the day.
Comfort is not only represented when you are inside your sleeping bag.Because you're carrying your pack most of the day, weight and packed size also play a huge role in your comfort during the day.

If you spend more time carrying the bag than you do inside of it, we suggest prioritizing weight and bulk (comfort while in your pack) over comfort while sleeping. The Marmot Phase, Patagonia 850, REI Co-op Igneo 25, and Kelty Cosmic Down were also top scorers for the comfort metric. We especially enjoyed how both of the Marmot Phase models provided an excellent hood design, which allowed us to stay cozy without feeling claustrophobic.

The spacious cut Cosmic Down (right) offers above average leg room and is an excellent option for tummy and side-sleepers of for folks who just want a little more room. Shown compared to the Western Mountaineering MegaLite (left) and Western Mountaineering UltraLite (center).
The spacious cut Cosmic Down (right) offers above average leg room and is an excellent option for tummy and side-sleepers of for folks who just want a little more room. Shown compared to the Western Mountaineering MegaLite (left) and Western Mountaineering UltraLite (center).

Packed Size


Packed size is how compressible a given model is. Overall compressibility is most heavily influenced by down quality (fill power) or type of synthetic insulation, shell fabrics, bag-dimensions, and features. Higher quality down, lighter fabrics, and simple features create the most compressible bags.


Everyone wants a more compressible bag, as it either gives us more room in our packs or lets us take a smaller, lighter weight pack for a given objective.

The Spark III in the lightweight Black Diamond Betalight shelter on a trans-Sierra backpacking trip. The longer the trip  the more important weight and packed size becomes.
The Spark III in the lightweight Black Diamond Betalight shelter on a trans-Sierra backpacking trip. The longer the trip, the more important weight and packed size becomes.

The most compressible bags in our review are the Marmot Phase 30 and Western Mountaineering SummerLite, closely followed by the Sea to Summit Spark III and Mountain Hardwear Phantom Spark 32. All of these bags are 10-15% smaller than the Western Mountaineering MegaLite, Western Mountaineering Ultralite, and Marmot Phase 20, which did compress impressively small for 20°F bags. The REI Co-op Igneo 25, Kelty Cosmic Down, The North Face Hyper Cat 20, and the Mountain Hardwear Hyperlamina Spark provide a budget-friendly option while remaining compressible.

To make a more accurate comparison between the bags  we compared each bag's compressibility  both in its included stuff sack and in an (often better-fitting) aftermarket compression sack  since that's the route most people are going to take.
To make a more accurate comparison between the bags, we compared each bag's compressibility, both in its included stuff sack and in an (often better-fitting) aftermarket compression sack, since that's the route most people are going to take.

Versatility


Three-season models, meant to be used across the range of Three Seasons are built to handle a wide range of conditions. They must function on warm summer nights at lower elevations, as well as when the temperatures drop below freezing near treeline in the fall.


Versatility across environments, elevations, seasons, and temperatures is an important consideration when assessing a bag's performance and value as well as taking time to reflect on the types of trips you'll mostly be using this bag for. Some of the bags tested here, such as the Western Mountaineering Ultralight and WM MegaLite have continuous horizontal baffles that allow you to shift down from the top to the bottom of the bag, increasing comfort in warm conditions and warmth in cold conditions. We find these lightweight bags to be the most versatile in our test.

There is a lot of debate about goose down versus duck down. While goose down generally offers a higher quality because it often comes from older  larger birds  this isn't necessarily always the case. You just don't see it as much because there just isn't as much high-quality goose down out there as duck down. Photo: The Western Mountaineering UltraLite out for an extended early season trip in the High Sierra.
There is a lot of debate about goose down versus duck down. While goose down generally offers a higher quality because it often comes from older, larger birds, this isn't necessarily always the case. You just don't see it as much because there just isn't as much high-quality goose down out there as duck down. Photo: The Western Mountaineering UltraLite out for an extended early season trip in the High Sierra.

Other features that increase a bag's versatility is an ability to vent on warmer nights, meaning a longer zipper offers more versatility than a 1/3 length one. A little extra shoulder room to facilitate adding one (or more) layers can also be helpful on those colder adventures.

When assessing each bag's versatility  we gave higher scores to bags that allowed for better ventilation on warm nights and enough space to add layers on colder evenings.
When assessing each bag's versatility, we gave higher scores to bags that allowed for better ventilation on warm nights and enough space to add layers on colder evenings.

The Backcountry Bed 700 incorporates a built-in quilt that enables you to sleep as you would with a comforter. It also regulates temperature fantastically when compared with a traditional side zipper. The quilt can be tucked away wholly, engulfing its occupant when temperatures near the bag's comfort limit. Plus, there is ample room to layer up in both of these models, and you can open the bag up for warmer nights.

Rebecca Schroeder testing 3-season bags over a wide range of conditions on Mammoth Terraces  El Captain Yosemite CA.
Rebecca Schroeder testing 3-season bags over a wide range of conditions on Mammoth Terraces, El Captain Yosemite CA.

The North Face Cat's Meow is a budget-friendly bag that offers an exceptional amount of versatility and works well for shorter backpacking trips, car camping, and has been used by FAR the most times by OutdoorGearLab review staff on the side of El Cap (likely more than 50 ascents collectively).

Generally speaking  we have a slight preference for down for most backpacking and mountaineering trips as it is often lighter  more compressible  and offers superior longevity. However  we frequently reach for a synthetic bag for wet coastal hikes  kayaking adventures  and big wall climbing. So while we have a slight preference for down  a synthetic bag could be better for the climate/conditions you're traveling in  or if you want to support ethical animal rights or have allergies to down. Testing a Cat's Meow and a Hyper Cat while kayaking in Washington's San Juan Islands.
Generally speaking, we have a slight preference for down for most backpacking and mountaineering trips as it is often lighter, more compressible, and offers superior longevity. However, we frequently reach for a synthetic bag for wet coastal hikes, kayaking adventures, and big wall climbing. So while we have a slight preference for down, a synthetic bag could be better for the climate/conditions you're traveling in, or if you want to support ethical animal rights or have allergies to down. Testing a Cat's Meow and a Hyper Cat while kayaking in Washington's San Juan Islands.

Besides excelling at shorter trips in the backcountry the Cats' Meow and new lighter replacement The North Face Hyper Cat is a great option for car camping, kayak or rafting trips, or any occasion in which versatility is paramount.

Despite its overall pretty minimal design  the Phase features a small internal zippered pocket. While this pocket was too small for a smartphone  it was a great place to keep a watch or a headlamp to help keep these items from getting lost in the dark.
Despite its overall pretty minimal design, the Phase features a small internal zippered pocket. While this pocket was too small for a smartphone, it was a great place to keep a watch or a headlamp to help keep these items from getting lost in the dark.

Features and Design


We assessed the usefulness of each model's features and attempted to quantify how well they contributed to each option's overall ease-of-use as well as its general performance.


This variable encompasses shell fabric, zippers (or lack-there-of), draft tubes, neck baffles, hood-design, stash pockets, and additional items included with the bag like storage and compressions sacks.

The Western Mountaineering MegaLite (right) compared with the other widest/comfort oriented bags in our review: the Sierra Designs Backcountry Bed 3-Season (left) and the Nemo Salsa 30 (center). All of these bags were far more spacious than most and while they are fairly comparable in the torso area  you can see that the Salsa 30 offered the most room.
The Western Mountaineering MegaLite (right) compared with the other widest/comfort oriented bags in our review: the Sierra Designs Backcountry Bed 3-Season (left) and the Nemo Salsa 30 (center). All of these bags were far more spacious than most and while they are fairly comparable in the torso area, you can see that the Salsa 30 offered the most room.

Like many things in the outdoor world, not all bells and whistles are useful nor do they necessarily make a model perform better. They often add weight, increase bulk and in some cases reduce performance or add only negligible performance for a disproportionate about of weight.

Our testers assessed how useful and the quality of each bag's features and attempted to quantify how well they contribute to a bag's overall performance.
Our testers assessed how useful and the quality of each bag's features and attempted to quantify how well they contribute to a bag's overall performance.

Besides adding weight, complexity, another potential failure point manufacturers often attempt to charge more because they either perceive the bags has greater value or want the consumer to think the same. Nine times out of 10 in the world of sleeping bags, we think other than the basics many additional features rarely offset the added weight and in reality, there has much effect on warmth, comfort, or convenience.

Some small features can be convenient  like The North Face Cat's Meow's zippered pocket; it's big enough for a smartphone or a watch  which is helpful in keeping it near your head for setting alarms.
Some small features can be convenient, like The North Face Cat's Meow's zippered pocket; it's big enough for a smartphone or a watch, which is helpful in keeping it near your head for setting alarms.

The Sea to Summit Spark III was a high scorer in the features and design metric; the hood, compression sack, and overall design were impressive, though this model does not necessarily come with many "extras." Back to its design, it is super light and was an honest 25F bag, unlike our Lightweight Top Pick winner, the Marmot Phase 30. While it is lighter and warm enough for most backpackers, it does not provide the most warmth in our fleet.

The Spark III features a well-designed hood that helps capture heat with 14 ounces of 850+ fill power down. This bag is rated to 25F.
The Spark III features a well-designed hood that helps capture heat with 14 ounces of 850+ fill power down. This bag is rated to 25F.

Take stash pockets on sleeping bags, for example. It can be helpful to keep your watch with an alarm in the pocket, but it can be hard to hear the alarm through the down. If you roll in your sleep, waking up on your watch isn't exactly comfortable. In general, when it comes to features, smart designs scored well, and generally, less is more.

Most 3-season bags are designed to offer features intended to be used over a broad range of conditions  from hot coastal hikes to summer-season above treeline adventures. Photo Day-3 of the Ptarmigan Traverse at White Rocks Lake Glacier Peak Wilderness.
Most 3-season bags are designed to offer features intended to be used over a broad range of conditions, from hot coastal hikes to summer-season above treeline adventures. Photo Day-3 of the Ptarmigan Traverse at White Rocks Lake Glacier Peak Wilderness.

Important Accessories


Unfortunately, very few bags come with decent quality stuff sacks and many bags come with downright terrible stuff sacks. A couple of exceptions are the Mountain Hardwear Hyperlamina Spark 35, The North Face Hyper Cat, Sea to Summit Spark III, and the Hardwear Hyperlamina Phantom Spark 28 which all come with pretty nice compression sacks.

In general, we recommend purchasing a superlightweight compression sack to use over most models included stuff sack to maximize the compressibility of your bag. See our Best Sleeping Bag Stuff Sack Article for our recommendations for specific applications.

Most sleeping bags don't come with a very efficient compression or stuff sack. Because so much space can be saved in your pack (or allow you to take a smaller pack)  we'd recommend buying an aftermarket one.
Most sleeping bags don't come with a very efficient compression or stuff sack. Because so much space can be saved in your pack (or allow you to take a smaller pack), we'd recommend buying an aftermarket one.

Other Sleeping Bag Reviews


We also offer an Ultralight Sleeping Bag Review, which compares hoodless options, weighing only 31 ounces or less. If you're looking for a lightweight bag that will primarily be used for overnight trips where weight is a concern, we highly encourage you to consider one of the models found in the Ultralight Bag Review. Lastly, we offer a general Camping Sleeping Bag Review that compares large and luxurious rectangular bags that are too heavy to carry backpacking. These offer much more comfort than any model tested here and cost as little as forty dollars!!

The Sierra Designs Women's Backcountry Bed 800 (left) has more room for your arms to move around  whereas the Kelty Ignite is a more traditional mummy shape. Like unisex bags  women's bags come in many styles and configurations.
The Sierra Designs Women's Backcountry Bed 800 (left) has more room for your arms to move around, whereas the Kelty Ignite is a more traditional mummy shape. Like unisex bags, women's bags come in many styles and configurations.

Ian Nicholson

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