If you're researching buying a new backpacking sleeping bag, you've come to the right place! We analyzed over 90 possible options before selecting the top-performing 17 models and directly comparing them via a rigorous testing regimen. Our testing was mostly conducted in the field during backpacking trips through the North Cascades and the Sierra. On these trips, we traveled through various temperature ranges and weather conditions to assess their performance and overall versatility. We put them on our scales to weigh them ourselves and measured their packed volume to give you the best resources available to make an informed decision on how each model compares to one another. Whether you're looking for solid overall performance, the lightest and most compressible option, something that feels as close to your bed at home as possible, or a budget pick, we have some great recommendations for you.
The Best Backpacking Sleeping Bags of 2018
|Price||$450.00 at MooseJaw|
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|$458.95 at Backcountry|
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|$299.73 at REI|
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|$390.00 at MooseJaw|
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|$434.95 at Backcountry|
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|Pros||Spacious and comfortable cut, extremely light weight, among the most compressible bags in our review, Made in the USA, extremely versatile, best feeling fabric in our review||Light for warmth, fantastic hood design, cozy internal fabric, incredibly compressible, nice foot box, sweet internal zippered pocket||Warm for its temperature rating and overall super lightweight for its warmth, lighter than most 30°F models, extremely packable, cozy interior fabric||Lightweight, warmer than other 30F models, extremely compressible, fantastic feeling interior fabric, Made in the USA, zipper snags less frequently than other ultralight models||Lightweight, extremely packable, comfortable torso area dimensions, silky feeling fabric, sweet foot box|
|Cons||Included stuff sack is a little big and doesn't compress it as small as it otherwise could be, expensive||Small zipper is prone to catching||Tighter than average internal dimensions, on the more expensive side||Tighter than average interior dimensions, included stuff sack could offer better compression||Not easiest to ventilate, zipper snags fabric constantly, stuff sack doesn't compress bag well, so-so hood design|
|Bottom Line||If we could only have one bag this would be it, as it's nearly the lightest and most packable model that offers spacious dimensions and above average warmth.||One of the best overall sleeping bags on the market for its weight, warmth, and compressed size.||If you are looking for a performance-oriented model but run on the cold side, this model is warmer than many 25F models while being lighter than most 30F.||This superlight and extremely compressible model offers some of the best warmth to weight ratio of any option out there.||This model is designed to be as light and packable as possible while still maximizing warmth and only making a few sacrifices to comfort, ease-of-use and overall versatility.|
|Rating Categories||MegaLite||Marmot Phase 20||Phantom Spark 28||SummerLite 32||Rab Mythic 400|
|Total Weight (20%)|
|Packed Size (15%)|
|Features & Design (10%)|
|Specs||MegaLite||Marmot Phase 20||Phantom Spark 28||SummerLite 32||Rab Mythic 400|
|Total Weight (Pounds)||1.5 lbs||1.44 lbs||1.43 lbs||1.15 lbs||1.45 lbs|
|Fill Power||850+ Goose Down||850+ Fill Power Goose Down||Q.Shield™ DOWN 800-fill||850+ down||900 Fill Down|
|Temperature rating (F)||30 F||20 F||28 F||32 F||19.5 F|
We've just added the new ultra versatile The North Face One, the insanely light Rab Mythic 400, and the latest update to the solid all-arounder The North Face Cat's Meow. This review focuses primarily on sleeping bags geared towards backpacking and three seasons camping though many of these models are also great for car camping or summertime mountaineering. We have an array of Top Pick and Best Buy recommendations below that excel for specific needs and types of trips, and of course, check out our best overall recommendation, the Western Mountaineering MegaLite, which continues to dominate the field for our favorite do-everything. Once again, the Megalite wins our Editors' Choice award for its low weight, packed size, spacious dimensions, and warmth. If you want an ultralight sleeping bag or quilt, we've got you covered there too in a separate review. There is some overlap between these two categories.
Best Overall Model
Western Mountaineering MegaLite
If we could only have one sleeping bag for backpacking, summertime mountaineering, and 3-season camping, it would no question be the Western Mountaineering MegaLite. It offers fantastic across-the-board performance, including the impressive combination of being one of the lightest and most compressible options while also being one of the roomiest. Spacious enough for car camping, it's also light enough for long-distance backpacking trips or other adventures where weight and packed volume is at a premium. It's spacious upper dimensions also mean it is one of the better options for tummy sleepers. The materials are silky smooth and feel the among the very best against our skin. All these attributes combined to make it one of the most versatile models and our testers' favorite choice for nearly any 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. 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 or more of use with just standard care. While there are many excellent backpacking sleeping bags out there, the MegaLite is the best of the best.
Read review: Western Mountaineering MegaLite
Best Bang for the Buck
REI Co-op Igneo 25
The REI Co-op Igneo 25 wins our overall Best Buy Award, as it offers the best overall performance for the price. It's a superb balance of quality materials creating low weight, and solid compressibility 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 bags but a fraction of the price.
The only thing worth noting is our testers didn't find the Igneo lives 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 All-Around 20F Model
Marmot Phase 20
A few years ago when Marmot updated their backpacking sleeping bag line with their at-the-time-new Phase series, they didn't hold anything back where quality or performance was a concern. The culmination of that is the Phase 20, which easily is one of the nicest sleeping bags of its temperature rating on the market. This bag sports top-quality 850+ down fill and some of the lowest weight shell fabrics you can find. This combination equates to one of the lightest and most compressible bags (for its respective 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 in our overall scoring. 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, yet significantly less roomy than the MegaLite. It's also on the expensive end of the spectrum, but it sure does deliver for the price.
Read review: Marmot Phase 20
Top Pick for Fast and Light Adventures
Western Mountaineering SummerLite 32
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, though it certainly won't win many buyers in the comfort-first crowd. It is among the very lightest and most compressible models both in our review and on the market today but remains reliably warm, something many other superlight bags begin to slim the margins of.
It achieves its impressively low weight without resorting to shaving grams of insulation and marginalizing its temperature rating by offering slim, thermally efficient dimensions, plenty of super high quality 850+ down fill, and a constructing utilizing some of the nicest (and lightest) fabrics currently available. Another nice bonus is that it's 100% sewn and filled 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 bag's warmth to weight ratio is tough to beat.
Read review: Western Mountaineering SummerLite
Top Pick for Wet Conditions
The North Face Hyper Cat 20
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. It's 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.
Read review: The North Face Hyper Cat 20
Best Buy on a Tight Budget
Kelty Cosmic Down 20
The affordable, yet reasonably light and compressible Kelty Cosmic Down 20, wins 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 $170. This bag is far more durable and compressible than its 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 a few hundred more dollars in your wallet? And even though it's rated to 20F, it isn't that warm, so if you are a cold sleeper or usually camp in lower temperatures, you'll want something warmer. For most backpackers, though, 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 Cosmic Down 40 as well.
Read review: Kelty Cosmic Down 20
Top Pick for Cold Temperatures (AKA the warmest 20F model)
Western Mountaineering UltraLite
The Western Mountaineering UltraLite is an extremely toasty bag. By far the warmest model in our review, it is noticeably warmer 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.It's 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 Exceptional Comfort
Sierra Designs Backcountry Bed 700
The three-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 compress 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 is.
Read review: Sierra Designs Backcountry Bed 700
3-in-1 Versatile Value
The North Face The One
It is hard to get more value than The North Face One because of its unique design that packs in three separately rated sleeping bags for the price of one. This three-in-one design is a three-part design which is based around a common lower half along with two interchangeable uppers rated to 40F (synthetic insulation) and 20F (800-fill down) degrees respectably that when used together create a 5F bag worthy of winter camping. While gimmicky sounding at first (and trust us, we were skeptical), The One is exceptionally well executed and pulls off the 3-in-1 design well. It's also quite comfortable with a U-shaped zipper.This model's primary downsides are directly related to all the design aspects that make this 3-in-1 bag work, which all generally makes it heavier and less packable than a majority of the competition. There's a lot more zipper and fabric to this model, add to its weight and size significantly. However, if you don't have the money or the space for multiple sleeping bags, this one covers the vast majority of conditions that most folks are likely to encounter. Aptly named, this could be The One for you.
Read review: The North Face One sleeping bag
Analysis and Test Results
Your backpacking sleeping bag is likely the most important insulating layer that is carried on any overnight wilderness excursion as well as likely providing the best warmth-to-weight ratio of anything in your pack. After shelter, sleeping bags make up the next largest portion of pack weight and available space of any other piece of gear or clothing in your pack. Thus investing in a quality backpacking sleeping bag that is well-suited to your needs will have a significant impact on your backcountry adventure in addition to how good your night's rest will be. And nowadays, sleeping bags aren't just for backpacking and mountaineering; they are also the preferred bed of choice for car campers, travelers, backcountry skiers, winter campers, and couch surfers.
We have over eight years of testing the best backpacking sleeping bags on the market under our belt. Our expert testers go to the extreme to field test each model we include in our review for months on end. We weighed them ourselves, 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 or design aspects that added or detracted from their overall performance. We then rate each bag on its warmth, weight, packed size, features, sleeping comfort, and versatility. Below you can read about our testing of each comparison metric and the specifics of each category.
If you're on a budget, absolute performance pales in comparison to performance-per-dollar. Value isn't incorporated into our scoring matrix, but we know it is in yours. Our individual reviews do comment on our interpreted value for each model, though. Not surprisingly, there's a gradual upward curve where the scores tend to increase with price. But 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, or conversely the diamond in the rough that far out-performs its price.
With backpacking sleeping bags, a higher price tag usually trickles down from a higher-quality fill and lighter, high tech materials. When looking for a good value pick, cross-reference the bags' scores with their price. Some great options for their price include the Sierra Designs Backcountry Bed 700 ($250) and the REI Co-op Igneo 25 ($270), which won our Best Buy Award.
Warmth is mostly a product of how much 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 vast majority of cases.
The 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; 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. Closely related is the limited heat your body produces, which will be spread too thin in a broader cut, thermally inefficient model. This effect can leave you feeling cold even though, on paper, a given model might have more insulation than a narrower cut model but still won't feel as warm.
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 insulated jacket while sleeping inside these bags to boost the temperature rating on colder nights. The rest of the bags we reviewed are wider dimensionally speaking, and a majority of people could wear a mid, or even heavier-weight jacket (or two) to boost insulation on even 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.
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. While we didn't feel it excelled at any one rating, the 3-bags-in-1 The One sleeping bag offers two separate layers rated to 40F and 20F that when combined produced a rating of 5F offering the greatest versatility of warmth that we have ever seen.
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 are excellent options when sleeping at 40°F and above.
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.
We tested these bags in traditional backpacking type shelters including both classic three season and single wall tents, silk-nylon tarps, and under the open sky on warm nights and a handful of open bivies above tree-line on exposed alpine ridges. See the Buying Advice on how standardized testing has helped (or hurt!) manufacturers' 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.
The weight metric is as simple as it gets, though arguably among the most important qualities for any human-powered activity. The biggest factors in this category included insulation, zippers, material quality, and internal dimensions as well as other features.
In general, heavier bags use either synthetic insulation (which is weightier than down) or lower quality fill-power down (500-700) which is less lofty for a given weight. In short, more insulation must be used to obtain a certain level of loft (warmth) compared with higher quality down where less insulation can achieve the same loft/warmth. A majority of the highest performing bags use the best down (800-900 fill-power) along with lightweight, ultra-thin shell fabrics. A bag's cut and its overall dimensions also play a major factor in a given models weight as a slimmer cut bag not only require less overall materials, but are also nearly always more thermally efficient, and thus requires slightly less insulation to achieve a given temperature rating.
At 1 pound 1.6 ounces, the Marmot Phase 30 is the lightest bag in our review though it faces a host of close competition. While it wasn't the warmest 30F bag we tested, we still found it more than suitable for most backpacking and summertime mountaineering trips. The Western Mountaineering SummerLite is only a hair heavier but noticeably warmer (if our testers could quantify it, we would call it 5F warmer) than the Phase 30. The SummerLite is able to do this by sporting slightly more insulation and slimmer internal dimensions. If you run on the cold side 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 lb 6.5 ounces.
The Sea to Summit Spark III and the Rab Mythic 400 are also both crazy light for the warmth they provide and their respective temperature ratings. As a result, it is no surprise the both these models feature tiny gauge 1/3 length zippers and some of the lightest shell fabrics in our review with 10D for the Spark III and a review-thinnest 7D for the Mythic along with fairly slim dimensions.
What is so impressive with both the Marmot Phase 20 and the Western Mountaineering MegaLite is that they are a fair amount roomier and a touch warmer while only a misly two ounces heavier. 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 not so roomy to be thermally efficient).
While the Marmot Phase 20 is light, the Western Mountaineering UltraLite is 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 score high for warmth.
Among synthetic bags we tested, our review team was thoroughly impressed with The North Face Hyper Cat. While it's not 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 lightweight synthetic option and is a pound+ lighter than a lot of synthetic models out there - it's also lighter than several 30°F down bags. This is where The North Face One isn't that sweet. While its 3-in-1 design is innovative, all the extra zippers and doubled up layers of fabric make it the heaviest model in our review.
Comfort is a subjective category that depends on a combination of internal dimensions, the user's sleeping style, and a bag's 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.
How worth it is having more internal space? The answer is 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.
The Sierra Designs Backcountry Bed 700 is the most comfortable bag in our review, with the semi-rectangular Nemo Disco 30 being a very close second and the MegaLite and The One also scoring well.
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.
Best of all, this model weighs a respectable 1 pound 15 ounces. While we loved the Backcountry Bed 700 and found that it offers a mega comfort-oriented design, its lower dimensions are average and not as spacious as the WM MegaLite. The inner fabric of the Backcountry Bed is also not quite as comfortable as those found on the Megalite.
The Nemo Disco replaces the old Salsa and is one of the best backpacking 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 broad 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.
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 North Face One isn't particularly light but is among the roomiest bags we tested and its "U"-shaped zipper mean regulating temperature and getting the perfect tension are among the easiest in our review. The Kelty Cosmic Down is also spacious and quite comfortable despite its lower-quality fabrics.
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.
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, Rab Mythic 400, Patagonia 850, and REI Co-op Igneo 25 were also top scorers for the comfort metric with respectable weights. We especially enjoyed how both of the Marmot Phase models provided an excellent hood design, which allowed us to stay cozy without feeling claustrophobic.
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 pack or lets us take a smaller, lighter weight pack for a given objective. Every model we tested comes with a stuff sack or compression sack. While some were fine, most were not, meaning they did a poor job at minimizing the packed volume of each bag. Bigger stuff sacks have the advantage of being easier to compress the sleeping bag into. However, for the extra 10-20 seconds of effort, every single tester would rather have a more compressed sleeping bag. Stuff sacks are slightly lighter than compression sacks, but compression sacks do a far better job at minimizing packed volume and in our opinion are worth the extra 2-3 ounces in saved packed space.
The most compressible bags in our review are the Phase 30 and SummerLite, closely followed by the Sea to Summit Spark III and Mountain Hardwear Phantom Spark 32, and Rab Mythic 400. It is worth noting that both Sparks come with some of the better compression sacks of any model we tested.
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 among 20°F bags.
Three-season models are meant to be used across spring, summer, and fall and are built to handle the wide range of conditions potentially found within those seasons. They must function to not overheat their user on warm summer nights at lower elevations, as well as to provide warmth when the temperatures drop below freezing near treeline in the early spring and later into fall.
Versatility across environments, elevations, seasons, and temperatures is an important consideration when selecting a bag as well as the types of trips you'd like to embark on. Some of the bags tested here, such as the WM 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. While this is cool, no model offers as much versatility across climates than The North Face The One sleeping bag. Its three-in-one design allows this bag to function as a 40F bag, a 20F bag, and a 5F bag. While this versatility does come with a weight penalty, having one sleeping bag that can work well across such a broad range of temperatures could easily be worth it to some people.
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.
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.
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).
Besides excelling at shorter trips in the backcountry, the Cats' Meow and The North Face Hyper Cat are great options for car camping, kayak or rafting trips, or any occasion in which versatility is paramount. As synthetic bags, they handle wet weather much better than their down counterparts, remains warmer when wet and drying out faster.
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.
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.
Besides adding weight, complexity, or another potential failure point, manufacturers often attempt to charge more for feature-laden bags because they either perceive they have greater value or want the consumer to think the same. Nine times out of 10 in the world of sleeping bags, other than the basics, many additional features rarely offset the added weight and in reality, there isn't much effect on warmth, comfort, or convenience.
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.
The Sea to Summit Spark III and the Rab Mythic are both high scorers in our features and design metric, even though these bags aren't necessarily built with many "extras." The designs are well executed to be as lightweight as possible with a shorter length zipper, crazy light materials, etc.
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 super lightweight 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.
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. For those of you heading into the cold, check out our review of the best down sleeping bags for winter camping and adventuring. In addition, 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!! And of course, we also have a review of the best women's sleeping bags on the market.
— Ian Nicholson