What is the best 3-season sleeping bag?

One of the great joys of hiking is snuggling into your sleeping bag at the end of a hard day on the trail. Today’s bags provide outstanding warmth for their weight, as well as a number of technology that allow them to keep dry and function in a variety of environments. While we did include a few top synthetic models, the bulk of the bags on our list are filled with down, which is warmer, lighter, and more compressible than synthetic insulation. The best backpacking sleeping bags of 2023 are listed here. See our sleeping bag comparison table and purchasing tips below the choices for additional information.

Our Team’s Backpacking Sleeping Bag Picks

Best Overall Sleeping Bag: Feathered Friends Hummingbird YF 20
Most Comfortable Sleeping Bag for Side Sleepers: Nemo Disco 15
Best Budget Down Sleeping Bag: Kelty Cosmic 20
Best Ultralight Sleeping Bag for Warm Weather: Sea to Summit Spark 40
Best Winter/High-Altitude Sleeping Bag: Mountain Hardwear Phantom 0F
Best Sleeping Quilt for Backpacking: Enlightened Equipment Enigma Quilt 30

Best Overall Sleeping Bag

1. Feathered Friends Hummingbird YF 20 ($479)

Feathered Friends Hummingbird YF 20 sleeping bag

Temperature rating: 20˚F
Weight: 1 lb. 10 oz.
Fill: 14 oz. of 900-fill down
What we like: Serious hikers will appreciate the premium down and construction quality.
What we don’t: Pricey, with limited supply during high season.

A Feathered Friends sleeping bag is hard to match for the finest mix of comfort, quality, and warmth-to-weight. This Seattle-based boutique firm focuses in quality down goods and manufactures almost everything in the Pacific Northwest. Climbers stop here on their way to Mt. Rainier, Alaska, and far-flung destinations like the Himalaya, and it’s definitely worth a visit if you’re in Seattle (their store is right across from the REI flagship). And with a direct-to-consumer model, Feathered Friends sleeping bags and other down products are exceptionally well-made and competitively priced for what you get.

For 3-season use, the Hummingbird YF is our favorite sleeping bag on the market. It’s filled with 14 ounces of 900-fill goose down, has a water-resistant 20-denier Pertex Quantum shell, and weighs a manageable 1 pound 10 ounces for the 20-degree variant (in our experience, Feathered Friends bags run warmer than their listed ratings). And, although $479 is a considerable outlay, the Hummingbird is constructed to last: after almost a decade of usage, our bag shows no evidence of wear and is still as toasty as the day we got it. Also, when compared to the popular Western Mountaineering UltraLite below (also certified to 20 degrees Fahrenheit), it is somewhat lighter and substantially less expensive. For those who want to cut even more weight, Feathered Friends also makes the Hummingbird UL (1 lb. 8 oz.) with a thinner 10-denier shell and more premium 950-fill down for $569.

Most Comfortable Sleeping Bag for Side Sleepers

2. Nemo Disco 15 ($300)

Nemo Disco 15 sleeping bag

Temperature rating: 25°F ISO Comfort, 14°F Lower Limit
Weight: 2 lbs. 11 oz.
Fill: 22 oz. of 650-fill down
What we like: A spacious and comfy sleeping bag for individuals who toss and turn during night.
What we don’t: Heavier and bulkier in comparison to slimmer-cut bags with comparable temperature ratings.

With their sleeping bags, Nemo handles things a bit differently, and they’re a major hit among comfort seekers and side sleepers. Unlike slim mummy designs that cut dimensions to save weight, Nemo’s Disco uses a “spoon”-shaped idea. The emphasis is on comfort: the bag is broader than a normal mummy, especially at the elbows and knees, allowing side sleepers and others to move freely. The Disco is made with 650-fill, PFC-free hydrophobic down, a waterproof panel around the toe box for extra protection, and a built-in pillow sleeve. Two zipped “gills” run longitudinally at the top of the bag for ventilation, and unzipping them produces intended chilly patches to remove hot air in hot situations. In usage, we’ve found the system to be really useful on mild evenings.

The Nemo Disco’s main drawbacks are its weight and size. First, the greater roominess is due to the large design, which necessitates more fabric and down fill. The Disco 15 is far from light, weighing 2 pounds 11 ounces in ordinary size. Second, the fact that Nemo employs 650-fill down for this bag, which is obviously mid-range, doesn’t help (check out the 800-fill Riff 15 for a lighter but pricier alternative). Yet, if the spacious fit and distinct feature set appeal to you, the Disco 15 is an excellent choice. The Forte 20 is a comfortable synthetic bag from Nemo that costs $100 less.

Best Budget Down Sleeping Bag

3. Kelty Cosmic 20 ($170)

Kelty Cosmic 20 sleeping bag

Temperature rating: 32°F ISO Comfort, 21°F Lower Limit
Weight: 2 lbs. 10 oz.
Fill: 16.4 oz. of 550-fill down
What we like: Cheap for a cozy, well-made down sleeping bag.
What we don’t: It’s a little hefty and not as portable as more expensive ones.

Kelty produces low-cost gear that may pleasantly surprise rookie trekkers and those on a tight budget. The Cosmic 20 is one of the less expensive down sleeping bags on the market—certainly not from a big brand—but the ISO Comfort rating of 32 degrees Fahrenheit should keep you warm in most 3-season circumstances. It’s worth mentioning that Kelty just revamped the Cosmic series, with the main difference being a slightly lower fill-power (550 instead of 600) and a reduced price tag of $170. At under 3 pounds for the regular version, it’s our favorite budget down bag for 2023.

Take in mind that the Kelty Cosmic is not as light or packable as the more pricey alternatives on our list because to the lower fill-power down. The Feathered Friends Hummingbird above delivers about the same amount of warmth for notably less weight, but it is over three times the price and more brittle. It’s difficult to match the value of this Kelty line, which is also available in 40-degree and 0-degree variants, for those keeping an eye on their money and not counting ounces.

Best Ultralight Sleeping Bag for Warm Weather

4. Sea to Summit Spark 40 ($339)

Sea to Summit Spark 40 sleeping bag 2

Temperature rating: 44˚F EN Comfort, 40°F Lower Limit
Weight: 12 oz.
Fill: 6.3 oz. of 850-fill down
What we like: Hydrophobic down provides wet-weather assurance.
What we don’t: The 13-length zipper restricts airflow, making it barely warm enough for mid-summer usage.

The majority of the sleeping bags available weigh between 1 and 2 pounds and have temperature ratings as low as 20 degrees Fahrenheit. Although they are excellent all-around designs for a variety of circumstances and camping excursions, they are much too heavy and warm for minimalist missions in hot summer weather. The Sea to Summit Spark, a 12-ounce, 40-degree bag that packs down to the size of a 1-liter Nalgene bottle, is ideal for these circumstances. The Spark is surprisingly well-rounded for its weight: Unlike the Feathered Friends Tanager and Enlightened Equipment Enigma below, it comes complete with a hood and zipper, and its hydrophobic down offers great wet-weather assurance. All told, you’d be hard pressed to find a lighter, more functional design without bumping up to the 50-degree category.

But, with such a little purse, adaptability is restricted. To put it into context, our top-ranked Hummingbird has almost double the amount of down as the Spark, which is a pleasant bonus on cool summer evenings. Also, the Spark has a short, 1/3-length zipper, which gives you less wiggle area and restricts ventilation (the 40 F version of the Enigma weighs 14.7 oz. and has a far more versatile quilt design). Finally, the Sea to Summit’s 10-denier shell isn’t the thinnest here (the Tanager’s is 7 x 5D), but it will require considerable care when packing or sleeping outside on rough ground. But these shortcomings aside, the ultralight and ultra-compressible Spark will disappear into your pack or bike pannier better than just about any other sleeping bag, making it a solid choice for mid-summer outings at low elevations.

Best Winter/High-Altitude Sleeping Bag

5. Mountain Hardwear Phantom 0F ($650)

Mountain Hardwear Phantom 0F sleeping bag

Temperature rating: 13˚F EN Comfort, 0°F Lower Limit
Weight: 2 lbs. 10.6 oz.
Fill: 30 oz. of 850-fill down
What we like: Warmth-trapping features and a cozy loft for cold-weather excursions.
What we don’t: Shell is not water resistant.

A warm sleeping bag is required in cold situations, and Mountain Hardwear’s Phantom 0F has long been a favorite for winter camping and high-altitude treks. The Phantom is a toasty sanctuary from sub-freezing cold, filled with over 2 pounds of 850-fill down and features a high draft collar, 3D contoured hood, and draft-eliminating face gasket. The bag’s 2-pound-10.6-ounce weight is undoubtedly substantial in comparison to the 3-season competitors, but it’s amazing given the bag’s warmth: Mountain Hardwear keeps weight and bulk low with a thin 10-denier shell, lightweight zipper, and streamlined (yet still comfortable) profile. It all adds up to our favorite down sleeping bag for human-powered endeavors in the cold, including backcountry hut trips, snow camping, and expeditions up the world’s tallest peaks.

We’d be remiss if we didn’t add Feathered Friends’ Snowbunting EX 0. The Snowbunting, designed for serious activities, protects against drips and condensation with water-resistant Pertex Shield EX fabric. The shell is also somewhat thicker at 15-denier, and 40-denier ripstop reinforcements provide further security while sleeping next to your climbing gear. When compared to the Phantom, the Feathered Friends winter bag adds a few inches at the shoulder and hip for a roomier night’s sleep. The Snowbunting’s water-resistant shell reduces breathability somewhat and adds a few ounces to the overall weight, but for some, the increased assurance will be worth the cost. Overall, the Snowbunting ($679 for the normal length) is the superior bag if you anticipate having to ward off wetness, while the Phantom provides a more competitive mix of price and warmth-to-weight for dry circumstances and shorter journeys.

Best Sleeping Quilt for Backpacking

6. Enlightened Equipment Enigma Quilt 30 ($340)

Enlightened Equipment Enigma 30 sleeping quilt

Temperature rating: 30 degrees Fahrenheit (also available in 0, 10, 20, 40, and 50 degrees Fahrenheit)
Weight: 1 lb. 1.9 oz.
Fill: 12.4 oz. of 850-fill down
What we like: Super customizable and great warmth for weight.
What we don’t: There’s a wait time for custom models.

Some thru-hikers and ultralighters prefer sleeping quilts, which feature an open-back design that wraps around your sleeping pad and so saves even more weight. And because quilts are Enlightened Equipment’s bread and butter, it’s no wonder that their Enigma is at the top of our list for 2023. With a staggering 12.4 ounces of down centered around the front and side of the body, it delivers a major punch. 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 $340 for the 30-degree model, the Enigma is our top choice for a sleeping quilt.

We love sleeping blankets for their flexibility and weight savings, but they aren’t right for every traveler. The lack of a back makes it difficult to properly batten down the hatches in cold weather, and the lack of a hood means you’ll need to bring extra head protection (a beanie or hooded down jacket will do). Overall, we’d be hesitant to take the Enigma into genuine winter conditions, but we know people who do (it comes in a 0 F version). Finally, if you want to customize your Enigma (in terms of sizing, fabric weight, and colorway), be sure to factor in a wait time; on the other hand, Enlightened Equipment also offers a few stock versions that are ready to ship.

Best of the Rest

7. REI Co-op Magma 15 ($399)

Temperature rating: 28°F ISO Comfort, 16°F Lower Limit
Weight: 1 lb. 12.2 oz.
Fill: 15.9 oz. of 850-fill down
What we like: A lightweight sleeping bag that is less expensive than the competitors.
What we don’t: In our experience, the Magma line does not run as hot as claimed.

REI Co-in-house op’s goods have recently been remarkable, with a robust array of high-quality backpacking gear at reasonable prices. The current Magma 15 is a prime example: for $399, you get a luxury and warm camping bag filled with 15.9 ounces of 850-fill down (REI also offers a 30-degree variant for $349). On paper, it’s comparable to top-tier brands but less expensive (competing versions from Feathered Friends and Western Mountaineering cost $479 and $580, respectively). 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.

Yet, the REI Magma 15 has certain flaws in reality. Despite the excellent temperature rating, we’ve discovered that the bag doesn’t run as warm as advertised (which is one of the reasons we included the 15-degree version here rather than the 30-degree version). It’s tough to say why, but the varying baffle spacing might be a factor—the baffles on the bottom half of the body are substantially broader than the top half, which may have contributed to our legs and feet feeling a little cold. In addition, the shell can’t match the ultra-high-end feel of bags from Feathered Friends and Western Mountaineering. But you’d be hard-pressed to find a better value for the weight and warmth, earning the Magma a spot toward the top of our list.

8. Feathered Friends Tanager 20 CFL ($429)

Temperature rating: 20°F
Weight: 1 lb. 2.6 oz.
Fill: 12.6 oz. of 950-fill down
What we like: The hoodless design strikes a balance between weight and performance.
What we don’t: No zipper and very thin fabrics.

Models that trim weight using quality down, ultra-thin shell materials, simplified feature sets, and small dimensions abound in the ultralight sleeping bag sector. The Sea to Summit Spark is our favorite because of its simple design, but the hoodless Feathered Friends Tanager is a fascinating option. Its focused lightweight construction saves weight on features while not sacrificing insulation with quality 950-fill down. The result is impressive to say the least: the 20-degree Tanager weighs just 1 pound 2.6 ounces total but contains a whopping 12.6 ounces of insulation. Do the math—you get 6.3 ounces more down (of a higher quality) in a 6.6-ounce heavier build—and it’s even warmer for the weight than the Spark above.

The Tanager doesn’t make our top UL selection for a few reasons, including its zipperless design, lack of a hood, and ultra-thin fabric (you can literally see through the 7D x 5D Pertex Quantum shell). Moreover, most thru-hikers and fastpackers will not be trekking into sub-freezing weather, making the Tanager’s warmth a little excessive for most circumstances (it doesn’t help that you can’t zip up the bag for ventilation). Nonetheless, 3-season alpine climbers will find a lot to appreciate about this purpose-built backpack, and the weight savings outweigh the limitations. And for a full mummy design from Feathered Friends with a zipper, our top-ranked Hummingbird also comes in a UL version ($569), which features 14 ounces of down in a 1-pound 8-ounce build…

9. Mountain Hardwear Bishop Pass 15 ($275)

Mountain Hardwear Bishop Pass 15 sleeping bag

Temperature rating: 26°F ISO Comfort, 15°F Lower Limit
Weight: 2 lbs. 5.4 oz.
Fill: 21 oz. of 650-fill down
What we like: A little lighter and warmer than the Marmot Sawtooth below.
What we don’t: The tapered cut is not recommended for individuals who toss and turn.

There are several extremely costly sleeping bags on the market that employ 800-fill-power down or greater, as well as a handful of budget-friendly synthetic choices, but mid-range down products are surprisingly restricted. We like the Mountain Hardwear Bishop Pass in this category because it does a good job of bringing everything together at a fair price. At 2 pounds 5.4 ounces total weight, you receive a comfortable 26-degree ISO Comfort rating—a half-pound less than the similarly priced Marmot Sawtooth below. And this bag is both well built and comfortable, with premium touches like a generous draft collar to seal out cold and noticeably soft liner that feels supple and cozy against the skin. At a fraction of the cost of a high-end model like the Feathered Friends Hummingbird YF, we like the value of the Bishop Pass.

Remember that the Mountain Hardwear Bishop Pass manages to keep weight low by adjusting the bag’s shape. The usual size is 53 inches at the hip, while the Marmot Sawtooth and Kelty Cosmic are both 59 and 58 inches. We suggest one of the aforementioned alternatives if you are a side sleeper who tosses and turns during the night (or Nemo makes the roomiest bags out there). And for about the same price, the Sawtooth adds a few ounces of down and extra features for comfort, including an expandable footbox and dual-side zips at the collar. But for those who don’t mind a trimmer mummy cut, the Bishop Pass is a quality mid-range bag that will save you some weight.

10. Western Mountaineering UltraLite ($580)

Western Mountaineering UltraLite sleeping bag

Temperature rating: 20°F
Weight: 1 lb. 13 oz.
Fill: 16 oz. of 850-fill down
What we like: Lightweight, super comfortable, and well-built.
What we don’t: The Feathered Friends Hummingbird YF 20 is more expensive and heavier.

The gold standard for premium down goods is established by Feathered Friends, although Western Mountaineering is close behind. This San Jose-based firm specializes in down sleeping bags and provides a comprehensive variety for any kind of explorer, ranging from robust and waterproof expedition bags to featherweight blankets. The UltraLite is their full-featured 20-degree product, with 16 ounces of 850-fill down (5 in. of down loft), a wrap-around draft collar, and a full-length #5 YKK zipper. All in all, the longstanding UltraLite is Western Mountaineering’s most popular 3-season backpacking bag for shoulder season adventures and lower-48 alpine conditions, and for good reason.

The UltraLite features a thinner shell at 12 denier (the Hummingbird’s is 20D), somewhat lower-quality down, and weighs roughly 3 ounces more than the 20-degree version of the Feathered Friends Hummingbird YF above. Nonetheless, we believe Western Mountaineering’s shell materials are somewhat softer than Feathered Friends’, making the UltraLite the most comfortable 20-degree backpack on the market. The Alpinlite is a bigger version of this bag that adds 5 inches of girth in the shoulders and 4 inches in the hips while only adding 2 ounces of overall weight.

11. Patagonia Fitz Roy 30˚F ($429)

Patagonia Fitz Roy 30F sleeping bag

Temperature rating: 30˚F
Weight: 1 lb. 13 oz.
Fill: 800-fill down
What we like: Luxurious, eco-friendly fabrics and a one-of-a-kind front zipper.
What we don’t: Not competitively lightweight and packable.

The Patagonia Fitz Roy Parka is one of our all-time favorite heavyweight down coats, thanks to its sleeping bag-like warmth and loft. So when the Ventura, California-based firm introduced its sleeping bag series under the same name, we knew what to expect: luxurious, lofty down feathers, a smooth and flexible fabric, and superb construction quality. With a center front zip, internal pocket at the chest, and a thick hood inspired after Patagonia’s harshest winter parkas, the Fitz Roy pulls more design cues from their jacket line. And as we’ve come to expect, it’s sustainably designed through and through, including Advanced Global Traceable down, a PFC-free DWR finish, and recycled, solution-dyed nylon (solution dying conserves both energy and water).

Yet, despite Patagonia’s love for fast-and-light alpinism, the Fitz Roy is neither very light or packable, especially when compared to packs like the Feathered Friends Hummingbird and Sea to Summit Spark mentioned above. As a consequence, we don’t recommend it for lightweight hiking excursions or multi-day climbs. However, the Fitz Roy joins a competitive field of solid all-arounders, including the REI Co-op Magma 15 and Therm-a-Rest Parsec 20 (Patagonia doesn’t specify a fill weight, but the Fitz Roy’s 30-degree designation feels like its lower limit in our experience), and the front zip (complete with three zipper heads for venting at the top, bottom, and middle) offers a nice change of pace from more standard designs. Added up, the Fitz Roy is a solid offering from a brand we trust—and it also comes in a 20-degree version (2 lbs. 4 oz.) for $529.

12. Nemo Forte 20 ($200)

Nemo Forte 20 sleeping bag

Temperature rating: 32°F ISO Comfort, 22°F Lower Limit
Weight: 2 lb. 14 oz.
Fill: 29 oz. of synthetic (PrimaLoft RISE)
What we like: A roomy and comfortable synthetic bag.
What we don’t: While bulky, we enjoy the attached compression sack.

We nearly always choose down sleeping bags over synthetics for hiking since they pack down smaller and give greater warmth for the weight. Nemo sought to overcome this gap by equipping the Forte with relatively compressible PrimaLoft RISE insulation, and we believe they did a nice job overall in terms of mass reduction. Moreover, the bag takes the spacious form and roominess of the popular Disco above, substitutes a 32-degree ISO Comfort certification (the Disco is certified to 25°), and lowers the price by $100. Tack on an impressively soft interior, and you get a cozy setup for side sleepers and those who like a little extra room.

Considering all of the advantages, comparing the Nemo Forte to a down sleeping bag is a difficult task. At the same temperature rating, a down bag will almost always be lighter and more packable. The Marmot Trestles Elite Eco below is tapered like a classic mummy bag, but the Forte has notably more room around the elbows and knees (for an 8-oz. weight penalty). We really enjoy the attached compression sack and the gills, which enable you to vent heat without unzipping the whole bag. All in all, the Forte isn’t perfect, but it’s another creative option from Nemo at a good price.

13. Marmot Sawtooth 15 ($279)

Marmot Sawtooth 15 backpacking sleeping bag

Temperature rating: 27°F EN Comfort, 15°F Lower Limit
Weight: 2 lbs. 14.2 oz.
Fill: 24.7 oz. of 650-fill down
What we like: Comfort and breathability are enhanced with dual side zips and a footbox zipper.
What we don’t: Heavy and bulky for a backpacking bag.

Marmot’s Sawtooth is a high-value and highly featured sleeping bag for the recreational traveller that falls between between business and casual. The first thing that stands out about the Sawtooth is its extra zippers: Dual side zips at the neck allow for ventilation and simple entry and exit; at the foot, a zipper opens for more room and closes to lock in warmth. To top it all off, the Sawtooth has a substantial 24.7 ounces of 650-fill hydrophobic down, which is far more than most bags on our list. For those who run cold or want a little extra warmth for shoulder seasons (without breaking the bank), the Marmot Sawtooth is cozy, warm, and high on comfort.

Keep in mind that the Sawtooth’s 27-degree EN Comfort rating is adequate for most backpacking trips into the mountains and won’t have you constantly checking the weather before the trip, but it may be overkill for hot summer circumstances. Although ventilation zippers may assist extend the bag’s temperature range, they can add significant weight: The Sawtooth is about a half-pound heavier, somewhat bigger, and includes just a few ounces more down than the similarly priced Bishop Pass above. But the added features and space (the Marmot is 59 in. at the hip vs. the Mountain Hardwear’s 53 in.) could be well worth it for some. For a higher-fill-power option from Marmot, check out their more premium Hydrogen.

14. Therm-a-Rest Parsec 20 ($450)

Therm-a-Rest Parsec 20 sleeping bag

Temperature rating: 32˚F EN Comfort, 20˚F Lower Limit
Weight: 1 lb. 12 oz.
Fill: 16 oz. of 800-fill down
What we like: Fully featured for a relatively low weight.
What we don’t: While not as warm as the Hummingbird YF above, it is still heavy.

Therm-a-Rest has a vast range of sleeping bags for anything from lightweight hiking to car camping, and the Parsec expands on that experience. The Parsec 20 (also available in 0 and 32 variants) provides frontcountry comfort in a lightweight (1 lb. 12 oz.) and packable construction, with 16 ounces of 800-fill down and a slew of remarkable features. You get a smooth no-snag zipper with a draft tube (which wasn’t completely perfect in our tests but significantly reduced hang-ups), a down-stuffed foot pocket for increased warmth, and a convenient external pocket for supplies. We’ve tested the Parsec all winter in both backpacking and van-camping scenarios, and have been impressed with how plush it feels for such a streamlined weight and bulk.

The Parsec 20 goes head-to-head with premium bags like the Feathered Friends’ Hummingbird YF 20 above and Therm-a-Rest Hyperion below. One of the most noticeable variations between these bags is their size: At 62 inches at the collar and 57 inches at the hip, the Parsec is much larger than the Hummingbird and Hyperion (the Hummingbird is 58 and 52 in., respectively, while the Hyperion is 57 and 49.5 in.). The improved comfort comes at a cost in weight, and although being lighter, the Hummingbird is still somewhat warmer with 14 ounces of 900-fill down. But for a roomy, plush, and versatile bag for three-season use, the Parsec 20 is nevertheless a high-quality option for a bit less than the competition.

15. Big Agnes Sidewinder SL 20 ($300)

Big Agnes Sidewinder SL 20 sleeping bag

Temperature rating: 20°F
Weight: 2 lb. 4 oz.
Fill: 19 oz. of 650-fill down / Fireline ECO synthetic
What we like: Another lighter choice for side sleepers than the Nemo Disco.
What we don’t: Not as roomy as the Nemo.

For years, Nemo has ruled the market for side sleeper sleeping bags, but Big Agnes has finally stepped up to the plate with the Sidewinder. This bag has a lot going on: it’s reasonably spacious, has a unique zipper designed to stay out of the way when you turn over, a large hood with excellent coverage regardless of sleeping position, and extra padding (via synthetic insulation) at the hip and foot, which are major ground contact points for those who sleep on their side. If you toss and turn at night, the design is much more useful than a standard mummy bag and a possible contender to the Nemo Disco mentioned above.

How does the Sidewinder differ from the Nemo Disco? The form is most notable: the Big Agnes is sleeker in terms of measurements, measuring 61 inches in the shoulders and 55 inches in the hips (the Nemo is 64 and 59 inches, respectively). It’s difficult to argue with the added room, yet the Sidewinder weighs 7 ounces less (with identical 650-fill down and 30D shell). It also has an unique pillow pocket, like the Nemo, to keep your camp pillow (or packed down jacket) in place during the night. With a good number of comfort-related differences, finicky sleepers may prefer to try both bags out before buying, but the Sidewinder is undeniably a great addition to the side-sleeper market and priced right at just $300.

16. Montbell Seamless Down Hugger 800 #3 ($339)

Montbell Seamless Down Hugger 800 3 sleeping bag

Temperature rating: 39˚F ISO Comfort, 30˚F Lower Limit
Weight: 1 lb. 2.7 oz.
Fill: 800-fill down
What we like: The absence of baffles on the outside and interior diagonal baffles properly balance weight and comfort.
What we don’t: Shell is thin and fragile.

Montbell, like Western Mountaineering and Feathered Friends, is a prominent down expert, and their Seamless Down Hugger series is one of the most distinctive on the market. Rather than baffles, the Down Hugger uses a web of polyester threads (called the “Spider Baffle System”) to hold the insulation in place, resulting in greater warmth with less down (read: less weight) than standard designs. The liner has a spiraling elastic thread on the inside that expands with your motions and constricts to hug your body, effectively trapping warmth. Added up, the Seamless Down Hugger is an incredibly efficient sleeping bag that works with a range of body sizes and will make side sleepers happy, too.

The biggest downside to cutting weight is a lack of durability: The shell of the Down Hugger is constructed of Montbell’s Ballistic Airtight nylon, which is densely woven to boost tear resistance but is clearly thin (10D) and needs extra care to prevent snags and punctures. As a consequence, at 1 pound 2.7 ounces, the 800 #3 is one of the lightest bags on our list, outweighing the Hyperion below in both weight and price. Although Montbell lists the Down Hugger 800 #3 as a 30-degree bag, take in mind that this is the bag’s Lower Limit rating. If you’re looking for something a bit different, Montbell offers the Seamless Down Hugger in a variety of fill weights (900, 800, and 650-fill) and temperature ratings (15, 25, 30, 40˚F), including “WR” models with windproof Gore-Tex Infinium shell fabrics and water-resistant zippers for added assurance in inclement weather.

17. REI Co-op Down Time 25 ($229)

REI Co-op Down Time 25 sleeping bag

Temperature rating: 35°F ISO Comfort, 25°F Lower Limit
Weight: 2 lb. 7 oz.
Fill: 16.6 oz. of 600-fill down
What we like: A good budget bag that is a little lighter than the Kelty Cosmic.
What we don’t: You can go cheaper for the same level of warmth.

For years, REI’s premier sleeping bag has been the Magma, but the Co-op provides another good bargain in the mid-range Down Time 25. It’s a wonderful alternative for weekend hiking excursions for people who don’t need the lightest and most packable gear. It’s made of 600-fill-power down and a moderately hardwearing 30-denier shell. Maybe most significantly, the Down Time costs $229, which is a fair price for a high-quality down bag that is also ecologically friendly.

The Kelty Cosmic, which is our top budget selection, is the major contender to the REI Down Time. Finally, the Kelty is $59 less expensive and somewhat warmer with a 32°F ISO Comfort rating, but it’s 3 ounces heavier and has a thinner 20-denier shell. Considering that a sleeping bag isn’t especially concerned about denier (it’s just used on the inside of your tent), we give the slight edge to the less expensive Kelty. But for those who backpack with their dog, are hard on their gear, or prefer REI products in general, the Down Time is a nice option.

18. Therm-a-Rest Hyperion 20 ($500)

Therm-a-Rest Hyperion 20 sleeping bag

Temperature rating: 32°F EN Comfort, 20°F Lower Limit
Weight: 1 lb. 4 oz.
Fill: 13 oz. of 900-fill down
What we like: An lightweight mummy bag that packs down to an impressively compact size.
What we don’t: Expensive; narrow cut with minimal bottom insulation.

Therm-a- Rest knows a thing or two about sleeping in the outdoors, as shown by the lightweight Hyperion. This sleeping bag has a 20-degree Lower Limit rating, 900-fill goose down, and a total weight of under 1 pound 4 ounces (that’s not a typo). That’s comparable to the hoodless Feathered Friends Tanager (1 pound, 2.6 ounces) above, which is rather amazing considering the Hyperion’s hood and zipper. Did we mention the extraordinarily compact packing size? For evidence, see the image in our purchasing recommendations below.

How does Therm-a-Rest do all of this with the Hyperion? The solution is a fairly aggressive shape that is severely tapered (read: not very spacious), with 70% of the down fill placed on top of the body. This implies you should carry a sleeping pad with a good R-value to insulate yourself from the ground, and if you flip over on your side and bring the bag with you, you’ll most certainly feel chilly. What’s more, the Hyperion features a half-length zipper, which is great for saving weight but offers little option for venting on warm nights (that said, it’s a step up from the zipperless Tanager). It’s a fairly compromised design and wildly expensive at $500, but the Therm-a-Rest is nevertheless a premium bag for ounce-counters who venture out in the shoulder seasons.

19. Marmot Trestles Elite Eco 20 ($169)

Marmot Trestles Elite Eco 20 backpacking sleeping bag

Temperature rating: 32.2°F EN Comfort, 21.6°F Lower Limit
Weight: 2 lbs. 6 oz.
Fill: 25 oz. of synthetic (HL-ElixR Eco Micro)
What we like: Good build quality and comfort.
What we don’t: We like the down Kelty Cosmic above at this pricing range.

With its diverse Trestles collection, Marmot has been a fixture in the world of synthetic sleeping bags for years. The Elite Eco 20 costs $169 and has a highly practical 32-degree EN Comfort rating, which should be enough for most 3-season settings, as well as a decent weight of 2 pounds 6 ounces. Marmot has recently enhanced the Trestles by using HL-ElixR Eco Micro insulation produced from recycled fibers, as well as a draft tube, which is uncommon at this pricing range. 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.

Finally, we rank the Marmot Trestles Elite Eco here because we believe there are many better alternatives for backpacking, and the Elite Eco’s pricing is high for a synthetic bag. If you don’t need the extra warmth, Marmot’s basic Trestles (30 F) is substantially less expensive at $109, and the Nemo Forte 20 above is the more comfortable alternative for around $30 more. The similarly priced down-filled Kelty Cosmic above, on the other hand, is comparable in weight but packs down smaller and lasts substantially longer (synthetic fill has a tendency to pack out over time). Unless water resistance is particularly important to you, we recommend going with the Kelty.

Backpacking Sleeping Bag Comparison Table

*Editor’s Note: We have included the EN or ISO Comfort grade in this table since we believe it is the most accurate point of comparison. Where available, we’ve included both the Comfort and Lower Limit values in the product specifications above. See our shopping tips for additional information on the differences.

Backpacking Sleeping Bag Buying Advice

Sleeping Bag Temperature Ratings

The temperature rating is the single most significant consideration when selecting a sleeping bag. Simply said, there are few things worse than a long, restless night shivering inside your tent, and we always feel it’s better to err on the side of caution when selecting your bag. We explain all you need to know about temperature ratings, including the EN/ISO standard, non-standardized models from cottage brands, and how to pick the proper rating, in the sections below.

Sleeping bag (Western Mountaineering UltraLite drying out)

The EN/ISO Rating System Explained
Instead of relying on the manufacturer’s marketing whims for a temperature rating, the sleeping bag industry has moved to standardize the system via the use of the EN (European Norm) and, more recently, the ISO (International Organization for Standardization). This criteria (previously known as EN 13537 and now known as ISO 23537) specifies how to assess the warmth of a bag and allows customers to conduct accurate product comparisons. Both standards include four numerical values: upper limit, comfort, lower limit, and extreme. The middle two ratings have the most significance for the majority of backpackers:

Comfort Rating: The temperature at which a typical lady can sleep well. Generally, women sleep colder than men, hence the importance of the comfort rating.

Lower Limit: The temperature at which a typical guy may sleep for eight hours without waking up. We rarely sleep for eight hours without waking on a backpacking trip, but you get the idea.

Of course, all EN/ISO ratings are based on averages, and we’ve found them to be too optimistic in general. As such, we’ve found that the higher EN/ISO Comfort rating is a better basis for across-the-board comparison than the EN/ISO Lower Limit, and therefore have listed it in the comparison table above (both ratings are included in the product specs when applicable).

Sleeping Bags Without an EN/ISO Rating
Several manufacturers, mainly small businesses like as Western Mountaineering, Feathered Friends, and Enlightened Equipment, do not submit their backpacks for EN/ISO testing. According to our observations, these brands are on the cautious side and take pleasure in providing highly accurate temperature values. The Feathered Friends Hummingbird YF 20, for example, is a very warm bag that kept our tester (an average guy) comfortable into the 20s, but the Kelty Cosmic 20—with a 21°F ISO Lower Limit—will be uncomfortable if temps go below freezing. As a result, we’ve found that in most cases the EN/ISO Comfort rating (the Cosmic’s is 32˚F) offers the best point of comparison to unrated designs.

Sleeping bag (Feathered Friends Swallow Nano)

Choosing the Right Temperature Rating
When selecting a temperature rating for your bag, look particularly at the EN/ISO numbers (where relevant), not simply the temperature shown in the bag’s name. As previously stated, we believe that the Comfort rating is the more realistic of the two values. You may also use the mentioned grade for non-EN/ISO-rated backpacks from high-end manufacturers like Feathered Friends and Western Mountaineering. To be safe, it’s a good idea to leave a considerable buffer (10 degrees or more) in both circumstances. For example, if you expect nightly lows around freezing (32 F), use a bag rated at 20 to 25 degrees. Additional considerations to consider are your age (people often don’t sleep as warmly as they grow older), whether you sleep chilly or warm (gender may also play a role here), and whether you’ll be sleeping in a tent or open-air.

The majority of backpacking sleeping bags (including the bulk of the types on the list above) are 3-season, with temperatures ranging from 20 to 30 degrees Fahrenheit. We enjoy the adaptability of these designs: you can unzip the bag and keep quite comfortable in the summer, but they also allow for spring, autumn, and alpine camping when the temperature drops to freezing or below. Summer bags have lower temperature limitations around 40 degrees and provide the least amount of tolerance for mistake, but they are light enough for warm-weather usage at low altitudes. Finally, winter or expedition bags are the warmest of all and overkill for most recreational backpackers (we don’t include any here). Within this category, a model like the 0-degree Mountain Hardwear Phantom 0F 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 -10 degrees Fahrenheit and lower.

Sleeping Bag Insulation

Down vs. Synthetic Insulation
The dispute over down vs. synthetic is not limited to hiking sleeping bags. These fill types are used to insulate midlayers, camping bags, and even sleeping pads. One has the upper hand for a certain item of gear or clothing, and for hiking sleeping bags, we still give the distinct advantage to down fill. There are many primary reasons for this, including the best warmth-to-weight ratio, significantly superior packability (i.e., a smaller compressed size), and a higher level of warmth. The final one is a little subjective, but we all agree that down’s soaring warmth feels more sumptuous. Down varies in quality, as assessed by fill power (discussed below), but even a mid-grade down fill is a superb insulator.

Backpacking sleeping bag (Feathered Friends Tanager)

So why consider synthetic? Price is the most typical factor for most. Even a quality synthetic bag like the Nemo Forte 20 costs roughly $200, whereas a decent down bag costs twice as much (and more). Also, synthetic outperforms down in damp conditions. Although down’s wet performance has improved due to the introduction of hydrophobic coatings on the feathers, synthetic will insulate significantly better if moisture enters the bag. Thus, if you’re just starting out and want a low-cost solution, or you backpack in really wet weather, synthetic backpacks are a perfect option. See our article on down vs. synthetic insulation for a more in-depth discussion of this issue.

Backpacking sleeping bag (laying Nemo Forte 20 inside tent)

Down Quality: Fill Power
If you determine that down will be your insulation of choice, one of the first specifications to consider is the fill power of a certain down. It is a measurement of how much loft or fluffiness the down clusters have, which corresponds with warmth (note: both duck and goose down are measured in the same way). The greatest down fill power is 1,000, while most sleeping bags are closer to 500. In general, the greater the fill power, the higher the price of the sleeping bag. The lower the fill power, the heavier it must be to offer comparable amounts of warmth. While high fill powers in the 800s and 900s are ideal, don’t be put off by 550- or 600-fill—a it’s terrific way to save money on an otherwise good bag.

Down and Synthetic Fill Weight
The quantity of insulation filled into a sleeping bag is referred to as its fill weight. If it’s a close choice between two bags with the same sort of insulation (down or synthetic) and one or both lack EN or ISO ratings, you may compare fill weight to see which one will be warmer. A bag with a thin cut may have less insulation than a bag with a spacious shape, but offering comparable or even greater warmth. Fill weight is more useful in categories without EN/ISO ratings, such as down coats, although it’s useful here as well. It’s also a fantastic illustration of how much more insulation is needed for a synthetic bag to compete with down. In instance, the Nemo Forte takes 7 ounces more to reach the same temperature rating as the down-filled Disco.

Hydrophobic Down and Water-Resistant Fabrics

As down feathers become wet, they lose a lot of their capacity to insulate, thus manufacturers have made efforts to offer built-in protection in the form of hydrophobic down and water-resistant shell materials. In the case of hydrophobic down, the feathers are coated with a polymer that protects them from moisture and keeps them from clumping. In practice, this means you don’t have to be concerned about brushes getting wet inside or outside of your hiking tent—though you still don’t want to completely saturate your bag. Hydrophobic down adds a little weight, but we enjoy it a lot, particularly for trips to damp places like the Pacific Northwest or New Zealand.

Water-resistant shell materials are also used in certain sleeping bags to keep moisture at bay. We see this in bags like the Feathered Friends Hummingbird YF, which features a Pertex Quantum shell with YFuse technology and a durable water repellent (DWR) finish. The purpose of this combination is for moisture to bead up and roll off rather than soak through to the down feathers underneath. Whether you choose a bag with hydrophobic feathers, water-resistant materials, or both, bear in mind that these technologies only guard against light—think condensation in a tent or dew during an open-air bivy—and will do nothing to keep you dry and toasty in heavy rain.

Weight and Packability

Your sleeping bag, along with your hiking tent, is one of the heaviest and bulkiest things in your pack. The lightweight Sea to Summit Spark 40 weighs just 12 ounces, while the spacious and toasty Nemo Forte 20 weighs 2 pounds 14 ounces (which uses synthetic insulation rather than down). In general, employing premium fill-power down (800+), lightweight shell materials and zippers (typically half-length), and trimmer profiles saves weight. 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 sleeping bag comparison table above.

Sleeping bag (unpacking the Feathered Friends Tanager 20 CFL)

Packability is another major selling advantage of premium down. Real goose and duck down compresses in a manner that no synthetic can replicate, and it’s not even close. Due to the loft of the down and the use of thinner shell materials, higher-end down bags, such as the Feathered Friends Tanager, will be the most compressible. The least compressible alternatives will be lower fill-power and synthetic bags. Additional factors include the bag’s cut (a tapered cut will reduce cloth and filled size) and temperature rating (warmer bags have more insulation). Summer bags may use less insulation and will be more compressible as a consequence.

Backpacking sleeping bag (Therm-a-Rest Hyperion stuffed down)

Consider purchasing a compression sack to fully use your sleeping bag’s compact filled size potential (one of our favorites due to its waterproof construction is the Sea to Summit eVent Compression Dry Sack). Most sleeping bags come with merely a non-compressible stuff pouch, which does not do your sleeping bag justice in terms of how compact it can become. When using a compression sack, use caution—try to softly compress the bag so that it fits comfortably into your pack without overdoing it, and avoid storing your sleeping bag in a compression sack for lengthy periods of time, since this may permanently harm the down.

Durability and Shell Denier (D)

The denier (D) of the shell fabric, which measures its thickness, is often used to determine the durability of sleeping bags, and the greater the number, the thicker the thread. The Feathered Friends Tanager 20 is at the lightest end of the scale, with an exceedingly thin 7D x 5D fabric that you can actually see the feathers through. Most 3-season sleeping bags, on the other hand, fall anywhere between 10D and 30D. In general, sleeping bags are one form of outdoor gear for which we don’t place a high value on denier. Your bag goes from storage, to the bottom of your pack, directly into your tent. We’ve seldom punctured our sleeping bag, unless you put your dog inside your tent or carry it out by the campfire for additional warmth. But, considering their expensive cost, it’s awful if you do (we usually bring mending tape just in case), so take care with the things inside your bag and tent.

Drinking tea in mountains (Sea to Summit Spark sleeping bag)

Sleeping Bag Dimensions: Profile and Length

Apart from factors such as warmth and down fill, the cut of a sleeping bag is an essential factor to consider. The girth (i.e. circumference) at the shoulders, hips, and feet (59″/51″/38″, for example) are the three most typical locations of measurement for sleeping bags, and they indicate how spacious or tapered the bag is. The shoulder and hip dimensions are the most important for comfort, hence we included them in the comparison chart above.

Zipping the middle zipper on the Patagonia Fitz Roy sleeping bag

Several lightweight sleeping bags reduce weight by having a tapered cut that uses less fabric and down. If you toss and turn during sleep or just like extra space, a larger bag might be considered (the spoon-shaped Nemo Disco 15 is a great example). The disadvantages of these bags are that they may feel draftier, may not hold heat as effectively, and frequently weigh more since more fabric and insulation are needed to occupy the bigger surface area. The good news is that many manufacturers make the same bag in varying widths. The Western Mountaineering Alpinlite is the wider version of the UltraLite, for example, and the Feathered Friends Swallow and Swift expand on the dimensions of our top-ranked Hummingbird.

Most sleeping bags are available in two or three lengths to accommodate men and women of varied heights. The usual size for men’s bags is typically 72 inches long, while the tall size is 78 inches long. If the bag does not have a women’s version, a short 66-inch variant is usually available. 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.

Women’s-Specific Sleeping Bags

Some backpacking backpacks have a separate women’s version with a distinct name, while others just have a “short” version of the same bag. What can you anticipate from a women’s bag? They normally have a somewhat different cut than men’s or unisex versions, with shoulders that are narrower and hips that are roomier. Also, the bags will have a bit more insulation (typically in specific places) and are often sold with a comfort rating rather than a lower limit. The men’s REI Co-op Magma 15 has a comfort rating of 28 degrees, while the women’s version has a rating of 17 degrees (their lowest limitations are 16 degrees and 3 degrees, respectively). All in all, we know women that buy women’s bags and others that buy men’s or unisex bags when they fit. The changes are minor, and it comes down to personal preference.

Women's specific backpacking sleeping bags

Maximizing Your Bag’s Warmth

After the purchase of your bag, there are a few things to consider in order to optimize warmth. The R-value of your sleeping pad, which measures how effectively it insulates you from the ground, is perhaps the most crucial aspect. R-values vary from 1.0 (almost no insulation) to around 9.5 (winter-ready warmth), with the typical 3-season traveler looking for something in the 3 to 4 range or more. Secondly, reducing drafts may help a lot—on a chilly night, make sure your zipper is completely closed and snug the draft collar and hood close to your neck and face. A warm hat may help keep a lot of heat in, and some wool baselayers can assist provide some warmth as well (we advise against cotton). Lastly, make sure you obtain the proper size bag, which we discuss in the “Dimensions” section above.

Backpacking Sleeping Quilts

Sleeping blankets are not the same as sleeping bags, but they are worth noting for individuals who run hot or prefer a lighter choice. A sleeping quilt (we recommend the Enlightened Equipment Enigma above, but you can find all of our recommendations in our buyer’s guide to the best ultralight sleeping bags and quilts) is a minimalist backcountry sleep system popular among ultralighters and thru-hikers, distinguished by an open back (read: no zipper) and an emphasis on weight savings. Quilts include enclosed or cinchable footboxes, attach to your sleeping pad through provided straps, and cinch around the neck to give wrap-around, draft-free cover.

The choice between a sleeping bag and a quilt boils down to personal taste. Quilts are popular among travelers (including one of our editors) because they are lightweight, concentrate insulation on the top of the body (your sleeping pad should take care of the underbelly), and breathe effectively on warm evenings. But, not everyone is happy with the trade-offs: you must pack sufficient head covers (a hat will do), the quilt/sleeping pad arrangement isn’t always ideal and might allow in breezes, and you may feel especially exposed on chilly nights. All in all, most recreational backpackers will prefer the coziness and simplicity of a lightweight mummy bag, but quilts are a viable option and especially great for warm nights.