Cozying into your sleeping bag at the end of a long day on the trail is one of the great pleasures of backpacking. And today’s bags offer exceptional warmth for the weight along with a range of technologies that help them stay dry and perform in a variety of conditions. The majority of the bags on this list are filled with down, which is warmer, lighter, and more compressible than synthetic insulation, although we did include a handful of top synthetic models as well. For more background information, see our sleeping bag comparison table and buying advice below the picks.
Temperature rating: 28°F ISO Comfort, 16°F Lower Limit
Weight: 1 lb. 12.2 oz.
Fill: 15.9 oz. of 850-fill-power down
What we like: A premium, lightweight sleeping bag for less than the competition.
What we don’t: From our experience, the Magma line doesn’t run quite as warm as suggested.
REI Co-op’s in-house offerings have been impressive of late, with a strong lineup of quality backpacking gear at reasonable price points. The latest Magma 15 is case in point: for $389, you get a premium and warm backpacking bag that is loaded with 15.9 ounces of 850-fill down (REI also makes a 30-degree variation for $339). In terms of specs, the Magma is right in line with top-tier brands but with less damage to your wallet. For example, the Feathered Friends Swallow YF costs $449 for the 20-degree version, and the Western Mountaineering UltraLite, also rated at 20 degrees, costs $525. The Magma isn’t cheap by any means—down is the most expensive insulator and for good reason—but it’s a solid value nevertheless, and especially with a member coupon.
In practice, the REI Magma 15 isn’t perfect. Despite the impressive temperature rating, we’ve found that the bag doesn’t run quite as warm as suggested (that’s one of the reasons we included the 15-degree version here instead of the 30). It’s difficult to pinpoint exactly why, but the variable baffle spacing could have something to do with it—the baffles on the lower half of the body are noticeably wider than the upper half, which may have left our legs and feet feeling a tad chilly. In addition, the Magma is a very well-built bag overall, but the shell can’t match the ultra-high-end feel of Feathered Friends and Western Mountaineering. But again, you’d be hard-pressed to find more sleeping bag for the money, which is why it’s our top pick for 2021.
See the REI Co-op Magma 15 See the Women's REI Co-op Magma 15
Most Comfortable Sleeping Bag for Side Sleepers
Temperature rating: 25°F ISO Comfort, 14°F Lower Limit
Weight: 2 lbs. 11 oz.
Fill: 1 lb. 1 oz. of 650-fill-power down
What we like: A roomy and comfortable sleeping bag for those who toss and turn.
What we don’t: Heavier and bulkier than slimmer-cut bags with similar temperature ratings.
Nemo does things a little differently with their sleeping bags, and they are a big hit among comfort seekers and side sleepers. Unlike slender mummy designs that trim dimensions to shave weight, Nemo utilizes a "spoon”-shaped concept on the Disco. The focus is on comfort: the bag is wider than a typical mummy, particularly in the elbows and knees, so side sleepers and others can roll around without feeling constrained. The Disco uses 650-fill (and now PFC-free) hydrophobic down, a waterproof panel around the toe box for added protection, and a built-in sleeve for a pillow. For ventilation, you get two zippered “gills” running lengthwise at the top of the bag, and unzipping them creates intentional cold spots to release hot air in warm conditions. In use, we have found the system to be very helpful on mild nights.
The biggest downsides of the Nemo Disco are weight and bulk. First, the spacious design that results in the extra roominess means more fabric and down fill are required. At 2 pounds 11 ounces for the regular size, the Disco 15 is far from ultralight. Second, it doesn’t help that Nemo uses 650-fill down for this bag, which is decidedly mid-range (check out the 800-fill Riff 15 for a lighter but pricier alternative). That said, if the roomy fit and unique feature set appeal to you, the Disco 15 is a great option. And for a cozy synthetic bag from Nemo for $100 less, see the Forte 35 below.
See the Nemo Disco 15 See the Women's Nemo Disco 15
Best Budget Down Sleeping Bag
Temperature rating: 33°F ISO Comfort, 21°F Lower Limit
Weight: 2 lbs. 10 oz.
Fill: 1 lb. 0.4 oz. of 550-fill-power down
What we like: Inexpensive for a warm and well-made down sleeping bag.
What we don’t: Decently heavy and not nearly as packable as more premium models.
For new backpackers and those on a budget, Kelty makes inexpensive gear that may pleasantly surprise you with its quality. The Cosmic 20 is one of the cheaper down sleeping bags on the market—definitely from a major manufacturer—but the ISO Comfort rating of 33 degrees Fahrenheit should keep you cozy in most 3-season conditions. It’s worth noting that Kelty updated the Cosmic line for 2021, with the major change being slightly lower-fill-power down (550 instead of 600), along with a considerably cheaper price tag at just $140. At under 3 pounds for the regular version, it’s our favorite budget down bag for 2021.
Keep in mind that the due to the lower-fill-power down, the Kelty Cosmic is not nearly as light or packable as the more premium options on this list. By spending up, you can get approximately the same level of warmth for less than half the weight with the Feathered Friends Hummingbird, for example, but that bag also happens to be three times the price and quite a bit more fragile. For those keeping an eye on their wallet and not counting ounces, it's hard to beat the value of this Kelty line, which also is offered in 40-degree and 0-degree versions.
See the Kelty Cosmic 20 See the Women's Kelty Cosmic 20
Best Budget Synthetic Sleeping Bag
Temperature rating: 36.1°F EN Comfort, 26.2°F Lower Limit
Weight: 3 lbs. 1 oz.
Fill: 1 lb. 14 oz. of synthetic (polyester)
What we like: Warm and cheap.
What we don’t: Not nearly as packable as down.
There’s no way around it: down is a premium insulator and very expensive, but you can save a lot by going with a synthetic sleeping bag. The Marmot Trestles checks many of the boxes that casual backpackers are looking for: it’s decently warm with a 36.1-degree EN Comfort rating, and synthetic insulation has improved significantly over the years, resulting in a cozy feel that works well both for short backpacking trips and car camping. Most importantly, we love the bargain-basement price of $99 for the regular size, which is a whole lot of bang for your buck.
Realistically, the Marmot Trestles is limited by its synthetic fill. Down wins out big time in terms of warmth-to-weight ratio and packability, and polyester is quite heavy in comparison and will take up a lot more space in your pack. This means that the Trestles isn’t ideal for longer trips or when space or weight are at a premium, but it’s a fine option for short outings or those with a large pack. On the flipside, synthetic insulation is much better at resisting moisture and continuing to insulate when wet, which is a bonus for those backpacking in humid conditions or wet weather. And for a higher-end version of this bag, the Trestles Elite Eco below is warmer and lighter albeit at a higher price point.
See the Marmot Trestles 30 See the Women's Marmot Trestles 30
Best Ultralight Sleeping Bag for Backpacking
Temperature rating: 20°F
Weight: 1 lb. 2.6 oz.
Fill: 12.6 oz. of 950-fill-power down
What we like: Hoodless design hits the sweet spot of weight and performance.
What we don’t: No zipper and very thin fabrics.
The ultralight sleeping bag world is chalk full of models that use premium down, ultra-thin shell materials, have trimmed-down feature sets, and narrow dimensions so that you can carry the least possible amount of weight on your back. We’ve tested a wide range of ultralight bags and all have their pros and cons, but our favorite model for 2021 is the hoodless Feathered Friends Tanager. Here's the concept: most backpackers bring a lightweight down jacket into the backcountry—you need it for use around camp and many people wear it to sleep. Unlike a mummy, the Tanager has no hood, so make sure to bring that down hoody or a warm hat. The result is a beast of an ultralight bag: the Tanager weighs just 1 pound 2.6 ounces total but manages to pack in a whopping 12.6 ounces of premium 950-fill down for a conservative 20-degree temperature rating.
To keep weight down, the Tanager incorporates a 7 x 5-denier Pertex Quantum shell fabric that is ultrathin by any standard (you literally can see the down through the shell), but if there is any piece of gear that doesn't require durability, it's your sleeping bag. In addition, it has a drawcord closure around the collar for sealing in warmth but no zipper. This cuts down on weight but does make the bag more difficult to vent on warm nights, although we found it to be less of a negative than anticipated. Plus, the Tanager is considerably warmer than competitors like the Western Mountaineering HighLite, and roomier and cheaper than the Therm-a-Rest Hyperion. For a full mummy design from Feathered Friends with a zipper, see the Hummingbird UL... Read in-depth review
See the Feathered Friends Tanager 20 CFL
Best Sleeping Quilt for Backpacking
Temperature rating: 30˚F (also available in 10, 20, and 40˚ versions)
Weight: 1 lb. 1.9 oz.
Fill: 12.4 oz. of 850-fill-power down
What we like: Super customizable and enclosed toe box helps with cold feet.
What we don’t: Plastic attachment buckles seem fragile.
Some ultralighters and thru-hikers opt for a sleeping quilt, which have an open-back design that wraps around your sleeping pad and therefore cuts even more weight. And quilts are the bread and butter of Minnesota-based Enlightened Equipment, so it’s no surprise to see their Enigma at the top of our list for 2021. It packs a serious punch with a whopping 12.4 ounces of down, and it’s all concentrated along the front and side of the body. Further, Enlightened Equipment quilts are handmade and can be customized into a wide variety of sizes (16 combinations of length and circumference), plus you have the option of 850- or 950-fill down along with a whole range of temperature ratings. Priced at a reasonable $290, the Enigma is our top choice for a sleeping quilt.
What are the shortcomings of the Enlightened Equipment Enigma? We like the elastic straps that attach it to a pad—or cinch the quilt closed, sleeping-bag-style—but we question the durability of their accompanying plastic clips, especially considering they’ll often be sandwiched between your body and the ground. And while we chose the Enigma for its draft-free enclosed toe box, Enlightened Equipment also makes the popular Revelation, which features a small zipper and drawstring at the feet that allows for more versatility as a blanket. Finally, as is the case with most cottage-industry brands, be sure to factor in a wait time. Most Enlightened Equipment products are made to order, which is great for customization, but products from larger companies often are available quicker.
See the Enlightened Equipment Enigma Quilt
Best of the Rest
Temperature rating: 30°F
Weight: 1 lb. 5.3 oz.
Fill: 11.5 oz. of 950-fill-power down
What we like: Premium down and build quality for serious backpackers.
What we don’t: Pricey and availability can be limited during peak season.
We introduced you to the unique and hoodless Feathered Friends Tanager above, but here is a little more background about the company. This boutique Seattle-based brand specializes in premium down products and makes just about everything in the U.S.A. Climbers stop in religiously before heading to Mt. Rainier, Alaska, and far-off places like the Himalaya, and it’s well worth a visit if you’re in Seattle (their new store is right across from the REI flagship). And being direct-to-consumer, their sleeping bags and other down products are exceptionally well-made and competitively priced for what you get.
For 3-season use, the Hummingbird UL is one of our favorite ultralight sleeping bags on the market. It’s stuffed with a generous 11.5 ounces of 950-fill goose down, has a thin but water-resistant 10-denier Pertex Endurance shell, and comes in at just 1 pound 5.3 ounces for the 30-degree version (in our experience, Feathered Friends bags run warmer than their listed ratings). And compared with the popular Western Mountaineering UltraLite below, the 20-degree Hummingbird UL is a full 5 ounces lighter and still $16 cheaper. All in all, this is a premium bag and the price reflects that, but you certainly get what you pay for with Feathered Friends (and then some).
See the Feathered Friends Hummingbird UL See the Women's FF Egret UL
Temperature rating: 26°F ISO Comfort
Weight: 2 lbs. 5.4 oz.
Fill: 650-fill-power down
What we like: A bit warmer and lighter than the Marmot Sawtooth below.
What we don’t: Tapered cut is not ideal for those who toss and turn.
There are a whole lot of very expensive sleeping bags on the market that use 800-fill-power down or even higher, and there a number of budget-oriented synthetic options, but the mid-range down offerings are surprisingly limited. In this category, we like the Mountain Hardwear Bishop Pass, which does a nice job putting it all together at a reasonable price. You get a cozy 26-degree ISO Comfort rating at 2 pounds 5.4 ounces total, making it slightly warmer and lighter than the Marmot Sawtooth below. And this bag is both well-built and comfortable, more so than the cheaper down bags on this list. At less than half the price of a high-end model like the Western Mountaineering Ultralite, we like the value of the Bishop Pass.
Keep in mind that the Mountain Hardwear Bishop Pass manages to keep weight low by tailoring the cut of the bag. The regular size is 53 inches in terms of the hip measurement, whereas the Marmot Sawtooth and Kelty Cosmic are roomier at 57 and 58 inches, respectively. If you are a side sleeper who tosses and turns throughout the night, we recommend choosing one of the aforementioned options (or Nemo makes the roomiest bags out there). But for those who don’t mind a trimmer mummy cut, the Bishop Pass is a quality mid-range bag at a good price.
See the Mountain Hardwear Bishop Pass 15 See the Women's MH Bishop Pass 15
Temperature rating: 20°F
Weight: 1 lb. 13 oz.
Fill: 1 lb. of 850-fill-power down
What we like: Lightweight, super comfortable, and well-built.
What we don’t: Pricier and heavier than the Feathered Friends Hummingbird 20 above.
The Western Mountaineering HighLite below is a trimmed-down ultralight bag for warmer temperatures, but the UltraLite is the more versatile and fully featured option. This is a true mummy bag for alpine conditions with a very healthy 1 pound (16 oz.) of 850-fill down. Unlike the HighLite, the baffles are continuous, the mummy hood is generously sized, you get a cozy draft collar, and premium materials from head to toe. All in all, the longstanding UltraLite is Western Mountaineering’s most popular 3-season backpacking bag and for good reason.
Compared to the 20-degree version of the Feathered Friends Hummingbird above, the shell is slightly thicker at 12 denier but comes with a lower-quality down, and the bag also weighs 5 ounces more. That said, we think Western Mountaineering’s shell fabrics are a little softer than Feathered Friends, which makes the UltraLite arguably the most comfortable 20-degree bag on the market. For more room, the Alpinlite is a wider version of this bag, giving you an extra 5 inches of girth in the shoulders and 4 inches in hips while only adding 2 ounces of total weight.
See the Western Mountaineering UltraLite
Temperature rating: 40°F ISO Comfort, 31°F Lower Limit
Weight: 1 lb. 15 oz.
Fill: 1 lb. 1 oz. of synthetic (PrimaLoft RISE)
What we like: A roomy and comfortable synthetic bag.
What we don’t: Bulky, although we do like the included compression sack.
For backpacking, we almost always favor down sleeping bags over synthetics—they pack down smaller and provide more warmth for the weight. Nemo attempted to bridge this gap by outfitting the Forte with relatively compressible PrimaLoft RISE insulation, and we think they did a good job overall with cutting bulk. In addition, the bag takes the generous shape and roominess of the popular Disco above, adds a 40-degree ISO Comfort rating, and slashes a significant $100 off the price (compared to the 30-degree version). For a cozy synthetic bag for side sleepers and those who like a little extra room, the Forte is a nice choice.
Despite all of the positives, it’s still an uphill battle in comparing the Nemo Forte to a down sleeping bag. At the same temperature rating, you’ll almost always be staring at an alternative that’s lighter and more packable. But the big selling points here are price and comfort compared to other synthetics: the Marmot Trestles above is tapered like a traditional mummy bag, whereas the Forte offers noticeably more space around the elbows and knees. We also like the gills, which allow you to dump heat without unzipping the entire bag, and the included compression sack. All in all, the Forte isn’t perfect, but it’s another creative option from Nemo at a good price.
See the Nemo Forte 35 See the Women's Nemo Forte 35
Temperature rating: 27.1°F EN Comfort, 15.6°F Lower Limit
Weight: 2 lbs. 8 oz.
Fill: 1 lb. 4.8 oz. of 650-fill-power down
What we like: Lots of warmth for the price.
What we don’t: Relatively heavy.
Most sleeping bags in this price range are built for temperatures around freezing or higher. But those that run cold or want a little extra warmth for the shoulder seasons without breaking the bank, try the Marmot Sawtooth. This bag is warm, comfortable, and the 1 pound 4.8 ounces of 650-fill down offer a nice compromise of performance and value. And with the added Down Defender treatment for water resistance, the Sawtooth is a well-thought-out and cozy backpacking sleeping bag for a reasonable $257.
Keep in mind that the 27-degree EN Comfort rating is ample for most backpacking jaunts into the mountains and won’t have you checking the forecast incessantly before the trip, but the Sawtooth may be overkill for warm summer conditions. And given that it’s not warm enough for true winter camping, it’s best for those who run cold or get out in spring and fall. For higher-fill-power options from Marmot, see the Hydrogen series below.
See the Marmot Sawtooth See the Women's Marmot Angel Fire
Temperature rating: 33.6°F EN Comfort, 24.4°F Lower Limit
Weight: 1 lb. 7.5 oz.
Fill: 10.9 oz. of 800-fill-power down
What we like: Light and comfortable.
What we don’t: Lower fill power and fill weight than our top picks.
Many of the bags on this list have temperature ratings in the 20-degree range—that’s the sweet spot for a 3-season all-rounder. But for summer backpacking where the temperature won’t really drop, the Marmot Hydrogen is a great way to save weight and money. This lightweight bag should keep you comfortable down to around freezing and a little colder in a pinch, which can work great for warm-weather backpacking trips into the mountains, and should be plenty for those staying at lower elevations. And less down fill means the total weight of the bag dips below 1.5 pounds.
Along with the Hydrogen, Marmot also offers the warmer Helium (13.5°F EN Lower Limit) and winter-weight Lithium (-4.5°F EN Lower Limit). All use 800-fill goose down instead of the 850- or 950-fill of Western Mountaineering or Feathered Friends respectively, but Marmot has a good formula going with these backpacking bags. If you like other Marmot products, we bet you’ll enjoy the Hydrogen too.
See the Marmot Hydrogen
Temperature rating: 32°F EN Comfort, 20°F Lower Limit
Weight: 1 lb. 4 oz.
Fill: 13 oz. of 900-fill-power down
What we like: An ultralight mummy bag with an incredibly small packed size.
What we don’t: Narrow cut with little insulation on the bottom.
Well, look what we have here: Therm-a-Rest—part of the larger family of brands that includes MSR—made big waves with the introduction of their ultralight Hyperion. The specs on this sleeping bag are staggering: a 20-degree lower limit rating, 900-fill goose down, and a total weight of just 1 pound 4 ounces (that’s not a misprint). That's on par with the hoodless Feathered Friends Tanager (1 pound 2.6 ounces) above, which is quite impressive. And did we mention the incredibly small packed size? See the photo in our buying advice below for proof.
How is Therm-a-Rest able to achieve this all with the Hyperion? The answer is a very aggressive design that is heavily tapered (read: not super roomy) along with putting 70 percent of the down fill on top of your body and much less on the bottom. This means that you should bring along a sleeping pad with a decent R-value to insulate you from the ground, and if you happen to turn over on your side and bring the bag with you, you’ll likely get cold. However, we can’t help but love the ingenuity, and for back sleepers looking for a premium ultralight bag, the Hyperion is a great option.
See the Therm-a-Rest Hyperion 20
Temperature rating: 15°F
Weight: 2 lbs. 5 oz.
Fill: 1 lb. 1 oz. of 650-fill-power down
What we like: Roomy and reasonably priced.
What we don’t: Not everyone likes the pad sleeve.
Big Agnes is perhaps best known for their backpacking tents, but they also offer a compelling line of sleeping bags. For 2021, we like the Anvil Horn 15 best: it’s roomy inside but still an efficient insulator, and competitively priced at $270. The 15-degree temperature rating does feel somewhat optimistic (Big Agnes does not use the EN/ISO rating system and isn’t as conservative as Feathered Friends or Western Mountaineering), but combining the Anvil Horn with a well-insulated sleeping pad should keep you comfortable on most 3-season backpacking trips.
The Anvil Horn’s most polarizing feature (like many bags from Big Agnes) is its lack of insulation on the bottom and attached sleeping pad sleeve. Some people love the integrated system that keeps you from sliding around and cuts out unnecessary down, but we have mixed feelings. Further, the Anvil Horn has their latest flexible sleeve that can accommodate both 20- and 25-inch wide pads, which active sleepers who like to rotate within their bag may find restrictive (there’s probably good reason why few other manufacturers have adopted this design). Pad sleeve notwithstanding, the Big Agnes is a relatively roomy and versatile sleeping bag that can be used for backpacking or camping, which is why it's included here.
See the Big Agnes Anvil Horn 15 See the Women's Big Agnes Daisy Mae 15
Temperature rating: 35°F
Weight: 1 lb.
Fill: 8 oz. of 850-fill-power down
What we like: Incredibly light at just 1 pound and a great option for summer thru-hikers.
What we don’t: Limited feature set and not warm enough for the alpine.
In the race to create the lightest possible hooded sleeping bag, Western Mountaineering wins with the HighLite. At just 1 pound even and with a healthy 8 ounces of 850-fill down, this bag enters into some serious ultralight territory. As we expect from this venerable California-based brand, the HighLite is extremely well-built, and with a listed 35-degree temperature rating, can work great for minimalist summer backpacking. It certainly won’t take you into the shoulder seasons or challenging conditions in the mountains, but it’s a terrific bag to have in your quiver and one that you’ll barely notice in your pack.
Where does the Western Mountaineering HighLite fall short? To achieve this low weight, the bag has a completely trimmed-down feature set: you get no draft collar, a simple hood that stretches the definition of the term “mummy,” box stitching instead of continuous baffles, and a half-length zipper (we find that this has a notable impact on your ability to ventilate). This all means that the HighLite should not be thought of as an alpine sleeping bag—summer temperatures at elevation often dip down to around freezing or lower, which will push its limits. But for thru-hikers looking for the lightest possible option, it’s an ultralight staple and for good reason.
See the Western Mountaineering HighLite
Temperature rating: 20°F
Weight: 3 lbs. 8 oz.
Fill: Synthetic (PolarLite)
What we like: Bargain-basement price and decent warmth.
What we don’t: Heavy and bulky for backpacking.
The sub-$100 price range typically is where you’ll find car-camping bags, but Teton Sports’ LEEF is a solid value option for casual backpackers. Despite being available for $75-$80 through most retailers, the LEEF has a host of features you usually find on premium sleeping bags: a full-length baffle along the zipper to prevent cold spots, insulation mapping that places more synthetic fill around areas prone to being cold, and an adjustable hood that cinches evenly around the face. The LEEF is only available in a single size—most bags above are offered in regular and long—but its 87-inch length makes it a fine choice for tall backpackers.
The 20°F temperature rating puts the Teton Sports LEEF in-line with our top picks, but at 3 pound 8 ounces, it’s the heaviest bag on our list. The culprit is the cheap synthetic “PolarLite” fill, which weighs more and is less compressible than down or a more advanced synthetic. As a result, backpackers who get out a lot or are looking to trim weight will want to steer clear of the LEEF, but for quick weekend trips with friends and family, it’s a nice way to get out without breaking the bank.
See the Teton Sports LEEF +20°F
Temperature rating: 32.2°F EN Comfort, 21.6°F Lower Limit
Weight: 2 lbs. 6 oz.
Fill: 1 lb. 9 oz. of synthetic (HL-ElixR Eco Micro)
What we like: Good build quality and comfort.
What we don’t: At this price point, we prefer the down Kelty Cosmic above.
Marmot has been a mainstay in the world of synthetic sleeping bags for years with its varied Trestles line. For $158, the Elite Eco 20 offers a very practical 32-degree EN Comfort rating, which should be work well for most 3-season conditions, along with a respectable weight of 2 pounds 6 ounces. Marmot has improved the Trestles of late by adding HL-ElixR Eco Micro insulation that is made from recycled fibers, and you get a draft tube, which is a rarity at this price point. And with the added moisture resistance of synthetic insulation, the Trestles Elite Eco is a comfortable sleeping bag that costs a fraction of the premium down options on this list.
In the end, we have the Marmot Trestles Elite Eco ranked here because we think there are far better options for backpacking, and the price of the Elite Eco is getting up there for a synthetic bag. For those who don't need the added warmth, Marmot's own 30-degree Trestles above is significantly cheaper at $99, and the Nemo Forte is more comfortable (and comes in 20-degree version if you want to match the warmth of the Marmot). Alternatively, the down-filled Kelty Cosmic above is around the same price and weight but will pack down smaller and take up less space. Unless water resistance is particularly important to you, we recommend going with the Kelty.
See the Marmot Trestles Elite Eco 20 See the Women's Trestles Elite Eco 20
|REI Co-op Magma 15||$389||28°F (ISO)||1 lb. 12 oz.||15.9 oz. of 850-fill down||63/57 in.||15D|
|Nemo Disco 15||$300||25°F (ISO)||2 lb. 11 oz.||1 lb. 1 oz. of 650-fill down||64/59 in.||30D|
|Kelty Cosmic 20||$140||33°F (ISO)||2 lb. 10 oz.||1 lb. of 550-fill down||62/58 in.||20D|
|Marmot Trestles 30||$99||36°F (EN)||3 lb. 1 oz.||1 lb. 14 oz. of synthetic||62/57 in.||70D|
|Feathered Friends Tanager||$369||20°F||1 lb. 3 oz.||12.6 oz. of 950-fill down||62/52 in.||7D x 5D|
|Enlightened Enigma||$290||30°F||1 lb. 2 oz.||12.4 oz. of 850-fill down||54 in./unavail.||10D|
|FF Hummingbird||$429||30°F||1 lb. 5 oz.||11.5 oz. of 950-fill down||58/52 in.||10D|
|MH Bishop Pass 15||$240||26°F (ISO)||2 lb. 5 oz.||650-fill down||62/53 in.||20D|
|WM UltraLite||$525||20°F||1 lb. 13 oz.||1 lb. of 850-fill down||59/51 in.||12D|
|Nemo Forte 35||$160||40°F (ISO)||1 lb. 15 oz.||1 lb. 1 oz. of synthetic||64/59 in.||30D|
|Marmot Sawtooth||$257||27°F (EN)||2 lb. 8 oz.||1 lb. 5 oz. of 650-fill down||62/57 in.||20D|
|Marmot Hydrogen||$341||34°F (EN)||1 lb. 7.5 oz.||10.9 oz. of 800-fill down||61/56 in.||20D|
|Therm-a-Rest Hyperion 20||$420||32°F (EN)||1 lb. 4 oz.||13 oz. of 900-fill down||57/49.5 in.||10D|
|Big Agnes Anvil Horn 15||$270||15°F||2 lb. 5 oz.||1 lb. 1 oz. of 650-fill down||69/60 in.||15D|
|WM HighLite||$370||35°F||1 lb.||8 oz. of 850-fill down||59/51 in.||12D|
|Teton Sports LEEF +20°F||$82||20°F||3 lb. 8 oz.||Synthetic||Unavail.||40D|
|Marmot Trestles Elite Eco||$158||32°F (EN)||2 lb. 6 oz.||1 lb. 9 oz. oz. of synthetic||62/57 in.||20D|
*Editor's Note: For the purposes of this table, we have included the EN or ISO Comfort rating, which we feel is the most accurate point of comparison. When available, we've listed both the Comfort and Lower Limit in the product specs above. For more on the differences, see our buying advice below.
- Seasons and Temperature Ratings
- The EN/ISO Rating System Explained
- Sleeping Bags Without EN/ISO Ratings
- Down vs. Synthetic Insulation
- Down Quality: Fill Power
- Down and Synthetic Fill Weight
- Hydrophobic Down
- Weight and Packability
- Durability and Shell Denier (D)
- Sleeping Bag Dimensions: Profile and Length
- Women's-Specific Sleeping Bags
- Sleeping Bags vs. Quilts
- Your Sleeping Pad R-Value Matters
- 2021 Inventory
Perhaps the single most important decision you’ll make when choosing a sleeping bag is the temperature rating. Simply put, few things are worse than a long, sleepless night shivering inside your tent, and we always believe that it’s best to err on the side of caution. Accordingly, we make our decisions based on the EN or ISO Comfort rating as opposed to the Lower Limit (more on the EN/ISO system below) and consider that against the lowest temperatures we might encounter. Below are the three categories of backpacking sleeping bags, with the most popular by far being the 3-season variety.
3-Season Bags (32°F to 20°F)
The majority of backpacking sleeping bags are 3-season. We love their versatility: in the summer, you can unzip and stay reasonably cool, but they also allow for spring, fall, and alpine backpacking where the temperature drops to freezing or below (this often happens in the night in the mountains even during the summer). In this category we love the REI Co-op Magma 15 (28°F ISO Comfort rating), which hits that temperature sweet spot for a wide range of trips and comes in at a very reasonable price point. If price isn’t an issue, Feathered Friends and Western Mountaineering make some of the finest backpacking bags on the market.
Sleeping Bags for Summer Backpacking (32°F and Above)
We are careful when recommending warm-weather bags because they leave the least room for error. If it’s summer and you’re camping in a hot place like Utah or at low elevation in a place like Colorado, a 32-plus-degree bag should do the trick. The advantage is that you can keep your pack lighter as these bags weigh as little as 1 pound and compress down incredibly small. However, one cold night can make for an uncomfortable trip. When carrying a true summer bag, bring a beanie and other layers that can help you keep warm if there happens to be an unexpected drop in temperature. To avoid any mishaps, we usually prefer to use 3-season bags unless we are going ultralight, and a borderline option like the superlight Marmot Hydrogen (34°F EN Comfort) is a good compromise. You can open them up at night when necessary or sleep on top on balmy nights.
Cold-Weather/Winter Sleeping Bags (20°F and Below)
You really have to know your gear and the conditions when climbing mountains or heading into the backcountry during the winter. For the purposes of this article, most of the bags on this list are of the 3-season variety and have temperature ratings from around 20 degrees to 34 degrees Fahrenheit. For winter camping, a bag like the 0-degree Feathered Friends Snowbunting is a good choice, and there are a number of options from climbing-centric companies like Western Mountaineering and Montbell that are rated down to 0°F or even lower.
Instead of depending on the manufacturer and their marketing whims for a temperature rating, the sleeping bag industry has attempted to standardize the system with the help of the EN (European Norm) and, more recently, the ISO (International Organization for Standardization). ISO testing is so similar to the previous EN method that we can talk about them as one in the same. This criterion (formerly known as EN 13537 and now known as ISO 23537) lays out guidelines for how to test the warmth of a bag and enables consumers to make accurate comparisons between products. Both standards give us two very important numbers:
Comfort Rating: The temperature at which an average woman can sleep comfortably. Generally, women sleep colder than men, hence the importance of the comfort rating.
Lower Limit: The temperature at which an average man can sleep for eight hours without waking. We rarely sleep for eight hours without waking on a backpacking trip, but you get the idea.
In addition, you may see references to the Upper Limit (the temperature at which an average man can sleep without excessive perspiration) and Extreme (the minimum temperature at which a standard woman can remain for six hours without risk of death from hypothermia). Of course, all of the EN/ISO ratings are based on averages and in general we've found them to be optimistic by around 10 degrees (we cover this in greater detail in the section below), but they are helpful in comparing two EN/ISO-rated bags. The majority of outdoor gear manufacturers use the ISO system (older models will still have EN ratings) but certainly not all of them—compliance is optional.
How the EN/ISO System Translates for You
First and foremost, we think that you should always leave a reasonable buffer in temperature so as to not to be disappointed (and save yourself sleepless nights). We've found the EN/ISO ratings to be too low, even when wearing a warm baselayer. For choosing the right rating, try to get an idea of the coldest temperature you'll be experiencing overnight. Check the weather forecasts and averages of areas you’re planning to visit to gauge the conditions. Once you have an approximate number, it’s a good idea to build in a buffer (we like 10 degrees) or more to avoid getting cold. Other factors to consider are your age (people typically don’t sleep as warm the older they get) and whether you are a cold or warm sleeper.
It’s also a good idea to have some extra clothing in case you need it. A warm hat can help keep a lot of heat in, and some wool baselayers will help add some warmth as well. And make sure to consider the R-value of your sleeping pad (more on this below), which will help to insulate you from the cold ground. Many people overlook their sleeping pad then become confused when their bag isn’t as warm as they had thought.
Some manufacturers do not EN/ISO-rate their sleeping bags, and typically it's smaller companies like Western Mountaineering, Feathered Friends, and Katabatic Gear. From our experiences, these brands actually are on the conservative side and take pride in offering very realistic temperature ratings. For example, the Feathered Friends Hummingbird UL 20 is a very warm bag and will keep the average man comfortable into the 20s, whereas the Kelty Cosmic—with a 21°F Lower Limit EN rating—will be cold if the temperatures dip below freezing. As such, we've found that the higher EN/ISO Comfort rating is a better basis for comparison than the EN/ISO Lower Limit, and therefore have listed it in the table above (both ratings are included in the product specs). If anything, being cold can be uncomfortable or even dangerous, and we recommend using the EN/ISO Comfort as the more realistic of the two. If your bag ends up being a little warmer, take that as a bonus.
The down vs. synthetic debate is not unique to backpacking sleeping bags. Midlayers, camping bags, and even sleeping pads are all insulated with these fill types. For a certain piece of gear or apparel, one has the leg up on the other, and for backpacking sleeping bags, we still give the clear edge to down fill. There are a few major reasons for that, including the best warmth-to-weight ratio, far better packability (i.e., a smaller compressed size), and a more premium warmth. The last one is a bit subjective, but it’s a clear consensus from us that down’s lofty warmth feels more luxurious. Down does vary in quality, which is measured in fill power (covered below), but even a mid-grade down fill is the superior insulator.
So why consider synthetic? The most common reason for most is price. Even a premium synthetic bag like the Nemo Forte 35 easily slides in at $200, while a nice down bag doubles that (and more). In addition, synthetic performs far better than down in wet weather. While there have been improvements in down’s performance in the wet thanks to the application of hydrophobic coatings on the feathers, synthetic will insulate far better if moisture enters the bag. So, for starting out, if you’re looking for a budget option, or you backpack in really wet conditions, synthetic bags remain a great choice. For an even more in-depth explanation of this topic, see our article on down vs. synthetic insulation.
If you decide down is going to be your insulation of choice, one of the first specs to look at is the quality of a specific down, known as its fill power. Specifically, it’s a measure of how much loft or fluffiness the down clusters have, and this correlates with warmth (note: both duck and goose down are measured in the same way). The highest down fill power is 1,000, and you’ll see cheaper sleeping bags closer to 500. Generally, the higher the fill power, the more expensive the sleeping bag. The lower the fill power, the more it must weigh to provide similar levels of warmth. High fill powers in the 800s are great, but don’t necessarily be turned off by 550- or 600-fill—it’s a great way to save money on an otherwise excellent bag.
Fill weight is the actual amount of insulation stuffed into a sleeping bag. If it’s a close call between two bags with the same types of insulation (down or synthetic) and one or both don’t have EN or ISO ratings, you can compare fill weight to get a better idea of which one will be warmer. Cut does matter here: a bag with a slender cut may have less insulation than a bag with a roomy cut despite providing similar or even more warmth. Fill weight is more helpful for a category like down jackets, which don’t have EN/ISO ratings, but it’s good to know here too. And it's a good visual for how much more insulation is required for a synthetic bag to compete with down. For comparison, the Nemo Forte requires 11 additional ounces to achieve approximately the same temperature rating as the down-filled Disco.
Unfortunately, down feathers lose much of their ability to insulate when wet, and synthetic insulation does a much better job in this department. Synthetic insulation, conversely, is much heavier, doesn’t pack down as small, and isn’t as warm, which are reasons that down is so prized. Gear manufacturers recently started treating down to make it more water-resistant. Essentially, a polymer is added to the down before filling the bag, and the result is the feathers are better protected from the moisture and don’t clump up as quickly. In use, this means you don’t have to worry as much about brushes with moisture inside or outside of your backpacking tent. A number of companies have named their proprietary treated down such as Sierra Design’s DriDown, Mountain Hardwear’s Q.Shield Down, Marmot’s Down Defender, etc.
We love the hydrophobic down movement. Yes, it adds a tiny bit of weight to the down, but it also adds a noticeable level of protection. Synthetic insulation still has its place for budget backpackers but nothing beats down, and particularly treated down. If you’re headed out in a wet area like the Pacific Northwest or New Zealand, buying a sleeping bag with hydrophobic down is a wise move. Fortunately, many manufacturers are moving in this direction, and it’s now the majority instead of the minority.
Along with your backpacking tent, your sleeping bag is one the heaviest and bulkiest items in your pack. Sleeping bags run the gamut from just 1 pound for a premium ultralight model like the Western Moutaineering HighLite, to over 3 pounds for a budget synthetic bag like the Marmot Trestles with far less packability. In general, weight is saved by using premium fill-power down (800+), thin shell fabrics and zippers, and trimmer profiles. As is the case with virtually all categories of outdoor gear, ultralight products tend to be among the priciest on the market. To better evaluate and compare weights, we’ve included this key spec in each product write-up and our handy sleeping bag comparison table.
In terms of packability, it’s another big selling point of premium down. Natural goose and duck down compresses in a way unmatched by any synthetic, and it’s not even close. In general, higher-end down bags like the Feathered Friends Tanager and Western Mountaineering HighLite will be the most compressible due to the loft of the down and use of thinner shell fabrics. Lower fill-power down and synthetic bags will be the least compressible options. Other indicators include the cut of the bag—a tapered cut will trim fabric and stuffed size—as well as the temperature rating (warmer bags have more insulation). Summer bags can get away with using less insulation and will be highly compressible as a result.
To take full advantage of the small stuffed size potential of your sleeping bag, consider picking up a compression sack (one of our favorites due to its waterproof construction is the Sea to Summit eVent Compression Dry Sack). Most sleeping bags only include a non-compressible stuff sack, but this won’t do your sleeping bag justice in terms of how small it can get. Do take care when using a compression sack—try to lightly compress the bag so that it fits easily into your pack without overdoing it, and don’t store your sleeping bag in a compression sack for extended periods as that can permanently damage the down.
For sleeping bags, durability is commonly measured by the denier (D) of the shell fabric, which represents its thickness, and the higher the number the thicker the thread. At the ultralight end of the spectrum, the Feathered Friends Tanager 20 uses an incredibly thin 7D x 5D fabric, which you literally can see the feathers through. Most 3-season sleeping bags fall somewhere in the 10D to 30D range, and some burly synthetics (like the Marmot Trestles 30) get as high as 70D. In general, sleeping bags are one type of outdoor gear that we don’t worry much about in terms of denier. Your bag goes from storage, to the bottom of your pack, directly into your tent. Unless you bring your dog inside your tent or haul the bag out by the campfire for extra warmth, we’ve seldom punctured our sleeping bag. That said, given their high cost, it’s unfortunate if you do (we always pack repair tape in case), so take care with the surrounding gear inside your pack and tent.
In addition to considerations like warmth and down fill, the cut of a sleeping bag is critical to how much you enjoy it. The three most common points of measurement for sleeping bags are at the shoulders, hips, and feet (59"/51"/38", for example), which give you an idea as to how roomy or tapered the bag is.
Many ultralight sleeping bags save weight by tapering the cut of the legs for less fabric and down. If you toss and turn at night or just prefer more space, make sure to consider a roomier bag (the spoon-shaped Nemo Disco 15 is a great example). The downsides are that these bags can feel draftier and may not retain heat quite as well, and often weigh more because more fabric and insulation are required to fill the larger surface area. The good news is that many manufactures make the same bag in varying widths. The Western Mountaineering Alpinlite is the wider version of the UltraLite, for example.
In terms of length, most sleeping bags come in two or three lengths that are meant to fit men and women of varying heights. For men’s bags, the regular size often is 72 inches long and the tall is 78 inches long. If the bag doesn’t have a women’s-specific version, you’ll often see a short 66-inch option. If you are on the border and want the hood to extend over your head, it’s a good idea to size up. Keep in mind that larger sizes do cost and weigh more and have a larger packed size.
Some backpacking bags have a women’s-specific version with a different name, and others simply have a “short” version of the same bag. What can you expect with a women’s-specific bag? They usually have a slightly different cut than men’s or unisex models that is narrower at the shoulders and roomier around the hips. Further, the bags will have a little more insulation, and often in targeted areas. And as is typical in outdoor gear, women’s sleeping bags often come in what are considered to be more feminine colorways. All in all, we know women that buy women’s bags and others that buy men’s or unisex bags when they fit. The differences are small and it’s mostly a matter a taste.
This article is about backpacking sleeping bags specifically, and quilts really are a different category altogether (we include the Enlightened Equipment Enigma above and categorize them separately in our ultralight sleeping bags and quilts round-up). However, they're worth mentioning for those who run particularly warm or want a lighter-weight option. Essentially, a sleeping quilt is a minimalist backcountry sleep system popular among ultralighters and thru-hikers. You technically can sleep in a quilt like a normal sleeping bag, but the narrow design favors opening up the back and connecting it to your sleeping pad (make sure to get a pad with the proper R-value for insulation). The end result cuts weight significantly and comfort too.
The sleeping bag vs. quilt debate comes down to personal preference. Certain people swear by quilts and love that they can shave even more ounces off the total weight of their pack. We’ve found that quilts aren’t as comfortable as mummy bags and have their downsides. You have to bring proper head coverage, which can add weight, the quilt/sleeping pad system isn’t perfect, and it takes a bit of time to set up each night. All in all, we prefer the coziness and simplicity of a lightweight mummy bag for most of our backpacking trips, but quilts are a viable option too.
We’ve written a lot about the temperature rating of your sleeping bag, but remember that your sleeping pad matters too. Keep an eye on the R-value, which is a measurement of how well the pad insulates you from the ground. R-values range from 1.0 (almost no insulation) to 9.5 (winter-ready warmth). A summer backpacker can get away with a low R-value, while the average 3-season backpacker should look for something in the 3 range or more. A true winter camper will want an R-value that exceeds 5 depending on the conditions. For more information, see our article on the best sleeping pads for backpacking.
We wanted to note that during this unique time, we have seen a number of supply-chain issues in the world of outdoor gear, and backpacking sleeping bags are no exception. You may notice that certain bags currently are low on inventory or unavailable in certain sizes, and a couple of our favorite models from last year like the REI Co-op Trailbreak and Igneo are no longer available (we are checking into whether they will be returning this spring). The good news is that there still are plenty of available models across many price points, and we will continue to update this article as more products hit the shelves.
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