A comprehensive guide to the best ultralight backpacking sleeping bags.
Tested and written by Appalachian Trail and Pacific Crest thru-hikers.
Lightweight: Nothing over 3 lbs.
Unless you are doing some alpine backpacking in sub zero temperatures, your bag should be able to provide adequate insulation without tipping the scale.
Sleeping bags are one of the “Big 3” backpacking gear items (tent and backpack being the other two) and are, therefore, one of your biggest opportunities to save weight. Most gear items weigh under a pound meaning different models and brands of that item might only differ by an ounce or two (a headlamp, for example). Sleeping bag models, on the other hand, can vary by several pounds. AKA - be mindful of this before getting a 5 lb. bag. As you can imagine, lightweight and high-quality bags are a premium gear item... and the price can reflect this.
Compressible: Get rid of the bulk.
This will vary a lot depending on your warmth and insulation needs. ie - a summer bag will compress smaller than a winter bag. By far, the number one thing that will account for the size of your bag (while packed) is the insulation fill. The fabric and design elements being the second and third. Down and synthetic fillings both have pros and cons (we'll get there in a sec), but down filled sleeping bags pack down to the smallest sizes.
Compression straps and stuff sacks can significantly cut down on the volume your bag occupies in your pack. Ideally, you want it compressed as compact as possible while on the trail.
Adequate Warmth: Build in the "20 degree rule of comfort".
Try to think of the degree ratings as only accurate for survival situations. Example: if you see “Awesome Model 20”, that means you will be able to survive in the sleeping bag if the temperature drops to 20 degrees Fahrenheit. Note this survival rating is a much lower threshold than what is actually comfortable to sleep in.
For me, I add about 20 degrees to the manufacturer's claim for a comfortable night's sleep. So, to continue with this same 20-degree bag example, I’d probably only feel comfortable sleeping in it in 40-degree weather (20 + 20 = 40), without an additional liner or warm clothes. Therefore, keep in mind how cold your nights will be, whether you are a hot or cold sleeper, what clothes you like to sleep in and whether you will be in a tent or not.
Temperature Ratings: Know how they're rated.
Temperature ratings on sleeping bags should be considered as a guideline only, as seasonal marked sleeping bags will differ depending on what region or country you are in. Examples: Summer (32° and higher), Winter (10° and lower), and 3-Season (10° to 32°).
Look for sleeping bags tested according to EN Standards and marked EN13537, which means the sleeping bag has undergone a "thermal manikin" test (which is a human model designed for scientific testing), not just independently tested by the manufacturer. Think of it as measuring the insulation, like the walls of a house.
The tests are conducted on the basis that a person is using a sleeping pad, is cocooned into a tent and is wearing one layer of thermal underwear. A "standard" man is aged 25, 1.73m in height and weighs 73kg, whilst a "standard" female is aged 25, 1.6m tall and weighs 60kg. Keep in mind that a man normally sleeps "hotter" than a female and that everyone is a different shape and size, with different levels of "self" insulation.
There are 4 standard temperature ratings to keep you warm:
Upper Limit - when a male can sleep without sweating, with hood and zippers open and his arms outside of the bag.
Comfort - this is when a female can comfortably sleep in a relaxed position.
Lower Limit - the temperature a male can sleep uninterrupted for 8 hours in a curled position.
Extreme - this is the minimum temperature for a female for 6 hours without the risk of death from hypothermia - albeit a touch of frostbite is still a possibility.
Sleeping bags with an EN Standards tag will affect the price of the sleeping bag, because the process is expensive. Always bear in mind that no amount of testing will be 100% accurate for you as an individual, as we all feel the cold differently. You can always take a layer of clothing off or unzip your bag if you get too hot, or simply add another layer of thermals and completely duck inside your sleeping bag if you happen to be on the cold side.
Spacious Interior: No boa constrictors.
After a long day of hiking, I really don’t want to be confined to a tight cocoon in my tent. Many ultralight sleeping bags cut weight by making them narrow. This is a tough balancing act - space versus overall weight and bulk. A snug sleeping bag will be warmer, as it minimizes the air space around your body, but you don't want to feel like you are in a straight jacket. Spacious sleeping bags give you freedom of movement, which is a dire necessity for restless souls, but they also require more precious body heat to fill.
There are 3 key measurements to take into consideration:
Length - opt for the shortest length that will fit your frame (to save weight), but ensure that your feet are comfy without being squished when you have the hood done up, as this will compress the insulation, which is what you don't want. Having a bit of extra room at the bottom of your sleeping bag gives you the option of having somewhere to stash some clothes and/or your boots. The regular male sleeping bags come in 2 standard lengths - up to 6ft and up to 6ft 6in. Female sleeping bags are usually up to 5ft 4ins and 5ft 10ins. When in doubt, get the extra length.
Shoulder girth - most of the male sleeping bags have a shoulder width of between 60 and 64 inches with narrow ones coming in at 58 inches. Female ones are slightly narrower ranging from 56 to 60 inches. An inch can make a huge difference on the snug level. The best way to determine the size you need is to test-drive a few different sized sleeping bags.
Hip measurement - most men's sleeping bag will measure in around 58 inches, whilst the women's tend to be a bit higher around 60 inches. Again, take a couple of sleeping bags for a test-drive.
Easy Entry and Exit: Go zipperless if possible (more on that below) or long have long-dual sided zippers.
You will get in and out of your sleeping bag a lot, potentially several times at night. Think for a second about where you typically sleep at night on the trail… in a small tent, possibly next to your partner, in the dark. Fumbling around with a snaggy zipper is the last thing you want.
Long length zippers, preferably opening on both sides so you can utilize both hands to read your kindle book or a map of the next day's hike, are the best to go for. They also offer more flexibility for ventilation. But, some sleeping bags have short zipper lengths to cut down on weight. If having your body fixed and constricted all the time doesn't bother you, then a short zipper could be an ultralight option.
Steer clear of metal zippers, as you need a zipper to be durable and reliable without the weight. Nylon and plastic zippers are the best for their quality, length and ability to adapt to various weather conditions, while slider zippers have special characteristics.
Nylon (coil) zippers have teeth made of coiled mono filament giving them super horizontal strength, which allows them to be longer than an average zipper. They are lightweight and fire resistant, with great durability and are easy to repair.
Plastic zippers (aka vislon) are commonly used in military equipment. The teeth of a vislon zipper are made out of a specific type of plastic that is molded onto a zipper tape giving it durability as well as making it waterproof.
Slider zippers have the popular features of "double pulls" and a "non-locking" function enabling sleeping bags to be opened from both inside and outside, also giving quick and easy access to get in or out of the sleeping bags.
Down vs Synthetic Insulation: One of the biggest backpacking debates.
Down feathers are lighter, warmer and pack smaller than synthetic insulation options. Down has an Achilles heel though - it loses loft and insulation ability when it gets wet. Losing insulation is a scary thought for winter backpacking. Down is more durable than synthetic fillings, but super expensive.
Most down filled sleeping bags have been treated with durable water repellent (DWR) in the factory process, which is fluoropolymer based and named "hydrophobic" down. This prevents the down filling from becoming a soggy mass with no ability to retain heat. It is also known as "dry down". This treatment makes it water resistant not water proof, so don't expose your sleeping bag to a torrential thunderstorm or drop it into a stream. DWR will wear off over time and will require reapplying.
A synthetic insulated sleeping bag dries faster than down, it is nonallergenic and is less expensive to buy. On the minus side, synthetic filling will give you less warmth for its weight, it is bulkier to carry and each time you compress it, the insulating power is reduced.
Technology has taken over from the old polyester fill for sleeping bags of the synthetic ilk and today there are 4 common primary fillers other than down.
Synthetic options on the market include:
PolarGuard and 3D PolarGuard Delta - PolarGuard was the original version with 3D PolarGuard Delta the perfected product that will give the same insulation ability, but with reduced bulkiness and weight. Commonly used in high quality three-season sleeping bags, it is easy to take care of, when wet it will not lose its insulation properties and you can wash it in cold water in a washing machine.
Quallofil - on the heavy and bulky side, you won't see it in the lightweight or high-end priced sleeping bags.
Hollofil & Hollofil II - only used in bargain basement sleeping bags as it lacks insulating ability, is heavy and quite bulky.
Thermolite - another cheapie sleeping bag filling with no insulation to keep you warm.
I keep my sleeping bag well protected in a waterproof stuff sack, inside a waterproof pack lined backpack, and I have never had a truly wet sleeping bag. If you can afford it and will keep it protected, I vote to go for down insulation along with protective storage.
Fill Power: ‘Fill-power’ is a measurement of the density of down fill and accounts for the overall warmth-to-weight ratio. This typically ranges from 600 to 950. The higher the number, the more ‘quality’ the feather insulation is. It is calculated on how many cubic inches 1 ounce of down can fill a testing device. And, of course, the higher the fill of power down, the more expensive it is. Generally an 850 fill power or higher is in the top quality bracket with warmth-to-weight ratio. Keep in mind that a 700-fill-power down sleeping bag rated +20°F will be lighter than a 600-fill-power down bag rated +20°F. A 3-season sleeping bag normally has a rating of at least 600, but if you are planning on being in sub-zero weather you should be considering 900 to 1000-fill-power.
Mummy vs Quilt: Mummy bags are the traditional cocoon-like sleeping bags with an added head wrap that will only leave your smiling face exposed. Because of the additional head coverage, mummy bags can be warmer, but they can be constricting and don’t allow for a wide range of sleeping positions. They are often secured with draw cords or zippers.
Quilts are like big insulated blankets. Some are completely rectangular and have no zippers at all. Others are sort of a half-breed, with a foot box to tuck your feet into and some straps or clips to close the open wall of the blanket. Quilts generally allow more movement. They also provide a lot of flexibility if you want to just have half of the bag on your body on warmer night.
Storage: Do NOT keep you sleeping bag stored at home in its' compression stuff sack. Over time, this can significantly decrease the loft of the fill and turn your sleeping bag into a flat blanket. Less loft = less insulation. Most bags come with a storage sack. They are often mesh and large, about the size of a garbage bag. The whole idea is to keep your sleeping bag in a fluffy state as much as possible, only compressing it down when on the trail.
Zipperless: More and more ultralight sleeping bags are going zipperless - after all, they are a breeze to open and close. Zippers can add weight and have the potential to wear out over time. If you do get one with a zipper, make sure it has a draft tube. This is a mini insulated flap to cover the, otherwise, exposed zipper seam.
Pad Loops and Sleeve: Connecting your sleeping bag to your sleeping pad, the pad loops are sewn-in straps whereby you can secure your sleeping bag and prevent it from slipping off the pad. A pad sleeve is used as an insulated sleeping pad when the design of the sleeping bag has eliminated the bottom insulation to reduce overall pack weight, making it compress smaller than a conventional sleeping bag.
What is a draft collar? A draft collar also known as face mufflers, a head gasket or neck baffles and it is the insulated collar around the hood of a sleeping bag to guard against cold weather. It is referring to the insulated baffles in the sleeping bag that sit around your head and neck to prevent heat from escaping or the cold leeching in. The draw cords are differentiated, so that you can feel in the dark which one does what, loosens or tightens your hood.
Do I Need 2 Sleeping Bags (Summer and Winter)? If money is no issue, by all means feel free to splurge. For the rest of us though, I think two is totally unnecessary. When in doubt, err on the warm side and get a full-on winter bag. A winter bag can be compatible in summer, but a summer bag just won’t cut it in winter. If the thick winter sleeping bag is too hot on summer nights, unzip it or just sleep on top of it in your bag liner.
Weight: 1 lb 10 oz
Warmth Rating: 20ºF / -6.67ºC, Fill: 950+ Goose Down
Price: $399.00 on featherfriends.com
Maximum comfort without compromising on weight, if the Flicker 20 UL Quilt sleeping bag is left unzipped, it will act as a large quilt and will accommodate 2 adults at a pinch. It is a full center-zip mummy sleeping bag that can be partially zipped. It's footbox can be cinched tight via a bottom drawcord, but you will lose approximately 6" of length. The crossover zipper design gives heat retention of a draft tube without weight or bulk, and the draft collar has 2 easily accessible drawcords. The continuous baffles let you position the down where you want it and the small webbing loops make it suitable to be used as a hammock under-quilt. You get to choose the color and the length. With its Pertex Endurance fabric, think 10 denier water-resistant and breathable fabric, the sleeping bag is lighter and has become a favorite of thru-hikers.
Weight: 1 lb 13 oz
Warmth Rating: 20°F / -7°C, Fill: 16 oz / 453 g Down
An efficient mummy sleeping bag that will keep you cozy in different climates, the UltraLite features a full down collar to help seal in the heat around your neck without adding excess bulk. High lofting down (16oz.) pumps the bag to 5" and it has a full-length YKK zipper. It comes in 3 different sizes ranging from 5'6", 6' and 6'6" with a shoulder girth of 59" or 60" in regard to the 6'6" sleeping bag.
Weight: 1 lb 14 oz
Warmth Rating: 22°F / -12°C, Fill: 850 g Goose Down
Price: $349.00 on rei.com
Giving you the best warmth-to-weight ratio, the Co-op Magma 10 sleeping bag has lightweight construction, water-resistant goose down and generous knee and foot space with a fitted silhouette. Cozy and super soft with its Downproof Pertex shell, its variable baffle spacing delivers high thermal efficiency. The zipper cover and internal anti-snag strip make for easy zipping and the contoured hood keeps you warm, with enough space for a low-profile pillow. There are 2 hood drawcords to allow for internal adjustment and an insulated yoke that fills the neck and shoulder gap, all of which help prevent heat loss. Coming in 3 sizes you can choose from "fitted" with a narrow profile for those on the skinny side who need more warmth, a "regular" that has a wider cut providing wriggle room and a "relaxed" version which is super roomy for those that prioritize comfort above all else.
Weight: 1lb 15 oz
Warmth Rating: 17°F / -8°C, Fill: 700 g Duck Down
Price: $299.00 on rei.com
Another sleeping bag under the label of REI Co-op is the Igneo 17 mummy sleeping bag with water-repellent down plus breathable fabric panels to create a sleeping bag perfect for wet conditions. Suitable for 3-season use, it offers superior loft and warmth with a Ripstop nylon shell of DWR finish. With a contoured and slightly angular hood, the headspace is nice and warm - like a less contricting mummy design. Complete with full-length draft tube to keep you warm.
Weight: 1 lb 4 oz
Warmth Rating: 20°F / -6.67°C, Fill: 850 g DownTek Treated
Price: $285.00 on enlightenedequipment.com
A handmade creation from Winona, Minnesota, this is an ultralight masterpiece. The Revelation is high on functionality, low in weight and super versatile. In the cold you can cinch down the sides with a pad attachment system and when it's warm, you just open up the zippered footbox and use it as a blanket. Able to adapt to any climate, the U shaped baffles keep the down where you want it all night long and the snap and drawstring neck closer fit securely around your shoulders, so there is no draft. There is a 20' zipper and drawstring to open and close the footbox as required and the pad attachment system using elastic straps and clips will keep it securely on your pad. They offer nearly endless combinations of fill, length, width and warmth rating so you select your desired specs.
Weight: 1 lb 8 oz
Warmth Rating: 25°F / -4°C, Fill: 850+ loft Ultra-Dry Down (90/10 European goose down)
Price: $469.00 on amazon.com
With a shell of 10D UL nylon treated with DWR and a soft liner with a high density weave, this sleeping bag has a transverse baffle construction and a contoured hood with a draw-cord that you can tighten to actually cover most of your head, if you want to really keep the heat in. Coming in 3 different weights, it is a no frills, top of the range option, if you are looking for weight versus warmth. It has a one directional 1/3 length zip with a toggle at the head to allow you to totally cocoon yourself and that is it. This sleeping bag will only give you the essential elements. Great for ultralight hiking and alpine climbing, it will take up little space in your bag once it is put into its compression sack, that you can compress further with the use of 4 toggles.
Weight: 1 lb 10 oz
Warmth Rating: 15°F / -9.4°C, Fill: 850 fill Power Down
Price: $315.00 on katabaticgear.com
This sleeping bag will really keep the cold out. Blanket in style, it has the option of a down overfill to give you a densely stuffed sleeping bag, if that is what you like. Overfill will pack the down more tightly into the sleeping bag reducing the chance of cold spots being created if the down shifts as you wriggle inside the bag. It will also increase the warmth of the sleeping bag by about 5-10°F, but the baffle height will remain the same as a sleeping bag that is not overfilled. With a zippered foot box, you will be able to completely open the sleeping bag into a blanket. So, so awesome. Its has an attachment system, down filled collar and draft guard covering the footbox. It comes in a variety of sizes from small, regular, long, regular wide and long wide.
Weight: 1 lb 4 oz
Warmth Rating: 20°F / -6.67 °C, Fill: 900+ European white Goose Down
Price: $339.00 on zpacks.com
Coming in 3 sizes of slim, standard and broad, the Solo Quilt is the lightest no-frills sleeping bag with either a three quarter length zipper or a full zip version and a draft tube. The enclosed foot box will keep your feet from popping out and you can either clip the sides of the quilt at the center to your sleeping pad with an extra strap (this weighs 4oz/11g) or tuck them under you. With its goose down filling in narrow relatively short chambers, there is less chance of the down being pulled to the sides as you move during the night. There is no hood, so you will need to go a size up if you want to pull it up around your ears. Ensure you invest in a goose down hood or a thick woolly hat to keep your head warm as an alternative to the ear muff solution. An elastic cord can be tightened around your neck to keep out any chilly drafts. The liner and the shell are treated with DWR and the sleeping bag can be hand washed in warm water. There is a hang loop at the foot so it can easily hang in a closet when not in use.
Weight: 2 lbs 2 oz
Warmth Rating: 20°F / -6°C, Fill: 650 fill power DownTek
Price: $269.95 on moosejaw.com
No zippers for gram counters and perfect for those that don't wish to wake a sleeping partner, this superlight technical down fill sleeping bag features a cocoon like build. Complete with a simple clip and loop system, instead of the high-maintenance zippers. Think zero noise as you climb in and out, unless you fall over your boots in the process. Coming in regular and long sizes, it has a relatively huge internal cavity for space. The full-length anti-draft collar wraps around the whole body which helps keep out that darn cold. Integrated diagonal baffles are in the structured sidewalls and a vaulted foot box creates heaps of wriggle room for your maybe big feet. You can un-cinch the hood with one hand and there are fabric loops on the interior for sleeping bag liners. It has a superlight shell fabric with high tear strength and water repellent finish.
Weight: 1 lb 7 oz
Warmth Rating: 30°F / -1°C, Fill: 850 Power Down
Price: $369.95 on moosejaw.com
One of the lightest quilt style hoodless sleeping bags on the market created from top-end fabrics, this sleeping bag has no extras, but it does promise you a warm and draft-free sleep. It has a strap and neck closure system, which makes it comfy in cold weather but easily discarded in warmer temperatures, when you can use it like a blanket or comforter. Great for side sleepers or restless bodies, you can tightly couple it with a sleeping pad by a simple draw-cord strap system in cool weather. It’s designed to be used with a sleeping pad to provide insulation against the ground and it works best with a thin self-inflating sleeping pad. The exterior is made of 10D Mylon Ripstop with DWR to prevent moisture compromising the down fill and the interior is lined with comfy and soft 10 Nylon Ripstop Mini-ripstop. There is not much in the way of colors to choose from and the cost may be an issue for some folks. Easy to get in and out of, the Siren Down Ultralight Quilt gives you the option of poking a leg out or folding down the top if you get too hot. It can also be utilized as a hammock.
Weight: 2 lbs 1 oz
Warmth Rating: 27°F / -3°C, Fill: 700FP PFC-Free Dridown
Price: $249.95 on amazon.com
Coming in a regular and a long size, the Backcountry Bed is an award-winning sleeping bag with a contoured shape and a zipperless design for more comfort. Light in weight and thermally efficient, it has an oversized integrated comforter to give you all the comforts of a snug bed, just like home. There are insulated hand and arm pockets and a stretch cord closure system to seal out the drafts. The self-sealing foot vents enable fast and easy ventilation. The sleeping pad sleeve will keep your pad where it is meant to be under you, to improve your overall comfort during the night.
Weight: 2 lbs 12.1 oz
Warmth Rating: 20°F / -6°C, Fill: Thermal.Q™ 100 g/m²
Price: $240.00 on amazon.com
Engineered to be the lightest and the warmest synthetic sleeping bag on the market, the HyperLamina Flame eliminates cold spots caused by traditional stitching and puts the warmth where you need it most, around your core and your feet. A mummy-cut sleeping bag with face gasket and single center half zip, the ThermalQ insulation compresses well and maintains an excellent loft. An ergonomic draft collar prevents the escape of warm air from inside the sleeping bag and the comfortable footbox gives you a natural foot position to ensure that you are comfy and toasty. The performance mummy cut does give you a snug fit by reducing girth, weight and bulk, whilst maximizing thermal efficiency. It comes in 2 sizes: regular and long.
Weight: 1 lb 4.7 oz to 1 lb 8.5 oz
Warmth Rating: 40°F / 4.4°, Fill: 800+ Goose Down
Price: $289.00 - $309.00 on amazon.com
Favored by ultralight backpackers as a mummy bag for less extreme temperatures. Its silky fabric makes it perfect for warm weather as well. A sleeping bag for 3 seasons, the cult status Atom by Marmot features a fold-down 2nd zipper for ventilation with easy access. The goose down is treated with Dow Defender to help block out any water in wet conditions. The main zipper has an anti-snag slider and the stretch tricot baffles keep the down from shifting during the night. There is an internal stash pocket to safely keep your goodies in and the multi-baffle hood with a drawcord limits any heat loss. The footbox is a bit tight, but also that much more snug in the notoriously cold feet extremities. The sleeping bag is complete with 2 hang loops for storing or airing out the bag, when not in use.
By Chris Cage
Chris launched Greenbelly Meals in 2014 after thru-hiking the Appalachian Trail for 6 months. Since then, Greenbelly has been written up by everyone from Backpacker Magazine and Bicycling Magazine to Fast Company and Science Alert. He recently wrote How to Hike the Appalachian Trail and currently works from his laptop all over the globe.
650-calorie fuel in a ready-to-eat package.