Best Ultralight Sleeping Bags of 2024

A fastpacking trip could begin where a snowmelt river runs out into a warm, sunlit meadow, but we fastpackers move quickly, so evening may find us well above treeline, where it’s chilly, even in the summer. So when it comes to finding the best ultralight sleeping bag, we want one that is easy to pack and carry but keeps us warm at night.

An ideal ultralight sleeping bag or quilt for fastpacking will compress down small enough to fit in a fastpack and be light enough that most people can comfortably run with it. Sleeping in throughout a wide range of temperatures will also be comfortable because, as most fastpackers and ultralight backpackers know, the wilds are capricious.

This year, we researched dozens of the best ultralight sleeping bags and quilts, tested 15, and chose eight for this list. The sleeping bags that made the cut are all light, warm, durable, comfortable, and packable. Our testers took the bags out on summer fastpacks throughout the San Juans of Colorado, shoulder-season trips through the deserts of the Colorado Plateau, and countless trips through the Wasatch of Utah.

Below are our favorite fastpacking sleeping bags of 2023. For more background information, see our buying advice, testing methodology, and frequently asked questions below the picks.

Make sure to check out our best fastpacking packs, best ultralight tents, and best ultralight sleeping pads guides as well!

Best Ultralight Sleeping Bags

• Best Ultralight Sleeping Bag with a Hood: Feathered Friends Swallow UL 20/30 Sleeping Bag – 20 Degree
• Best Ultralight Sleeping Bag with a Hood – Runner-Up: Montbell Seamless Down Hugger 800 #2
• Best Ultralight Sleeping Bag without a Hood: Feathered Friends Flicker UL Quilt Sleeping Bag – 20 Degree
• Best Ultralight Sleeping Bag without a Hood – Runner-Up: Zpacks 20F Full Zip Sleeping Bag
• Lightest Ultralight Sleeping Bag: Feathered Friends Tanager 20 CFL Sleeping Bag
• Best Ultralight Quilt: Katabatic Gear Alsek 22F Quilt
• Best Ultralight Quilt – Runner-Up: Enlightened Equipment Convert Sleeping Quilt – 20 Degree
• Best Budget Ultralight Quilt: Outdoor Vitals StormLoft Down TopQuilt 15

Best Ultralight Sleeping Bag with a Hood: Feathered Friends Swallow UL 20/30 Sleeping Bag – 20 Degree ($649)

Pros:

• Comfortable
• Extremely warm
• Dimensions fit all testers well

Cons:

• Expensive
• Minimal draft collar

The Feathered Friends Swallow UL 20/30 Sleeping Bag – 20 Degree is the warmest sleeping bag we tested that is still light enough at 27 ounces to qualify as a fastpacking sleeping bag. It is constructed from light, durable, downproof fabrics and crammed full of 16.8 ounces of 950-plus fill down.

We slept in this bag on several fastpacking trips in temperatures between 22 and 45 degrees Fahrenheit. Even down to 22 degrees Fahrenheit, we didn’t even feel like we were approaching the lower limit for this bag. It’s warm. One downside to this bag is that there’s no real draft collar, so to keep the cold out, you have to cinch the opening fairly snugly around your face. We’d prefer a draft collar to leave the opening uncinched, which we think would be more comfortable.

Several of our female testers were happy with the 60-inch shoulder width of this sleeping bag. We believe the Swallow UL 20/30 is a truly unisex sleeping bag, fitting a range of bodies better than other wider and narrower bags. It’s also just insanely warm. You won’t be disappointed if you can afford the high price tag.

This sleeping bag also comes in a 30-degree option if traveling in warmer climates.

Type: Hooded Mummy Bag | Advertised Weight: 27 ounces (766 grams) in size regular | Actual Weight: 26.95 ounces (764 grams) | Fill Weight: 16.8 ounces (476 grams) of 950-plus fill | Temperature Rating: 20 degrees Fahrenheit | Packed Size: 7 x 12.5 inches (17.8 x 31.75 centimeters), 9 liters

Shop the Feathered Friends Swallow UL 20/30 Sleeping Bag - 20 Degree

Best Ultralight Sleeping Bag with a Hood — Runner-Up: Montbell Seamless Down Hugger 800 #2 ($429)

Pros:

• Lightweight
• Reasonable price

Cons:

• Not as lofty as other options

The Montbell Seamless Down Hugger 800 #2 has been a go-to option for multiple members of the iRunFar testing team for several years, mainly due to its warmth-to-weight ratio. This 25-degree Fahrenheit bag has a unique baffle-less design that uses a combination of 800-fill down and synthetic fibers and weighs only 22.7 ounces. Instead of using baffles to hold the down in place, Montbell uses threads of yard to create something resembling a spiderweb inside the bag to trap the down in certain locations. This allows it to loft well while preventing it from moving around in the bag and reducing the number of seams. Since seams are one of the prime spots for heat loss, this makes the bag warmer. This bag seems to be a viable option well below its temperature rating. especially if you wear a layer or two underneath. The 10-denier Ballistic Airlight nylon taffeta shell doesn’t feel scary-light, and it’s held up to multiple summers and shoulder seasons of use without any sign of wear. We also didn’t notice any leaking of down.

The draft collar, as does the hood, cinches down tight to seal in warmth. There’s also a draft tube along the zipper to prevent heat loss. The tapered shape of the bag makes it thermally efficient, but it still provides enough room to stretch the legs out after a big day. While both of our testers for this bag were women in the mid-five-foot range, Montbell claims that this bag will accommodate a six-foot human. A long version is also available for taller people or those wanting a little extra space.

While this sleeping bag doesn’t loft quite as much as the Feathered Friends Swallow UL 20/30 Sleeping Bag – 20 Degree, it’s still very warm. And at a significantly lower price, it’s an excellent option for those looking for something that will keep them warm on nearly any summer mountain, shoulder-season, or winter desert trip.

Type: Hooded Mummy Bag | Advertised Weight: 23.9 ounces (677 grams) in size regular | Actual Weight: 22.7 ounces (644 grams) | Temperature Rating: 25 degrees Fahrenheit | Packed Size: 5.9 x 11.8 inches (15 x 30 centimeters), 4.7 liters

Shop the Montbell Seamless Down Hugger 800 #2

Best Ultralight Sleeping Bag without a Hood: Feathered Friends Flicker UL Quilt Sleeping Bag – 20 Degree ($529)

Pros:

• Very light
• Conservative temperature rating
• Comfortable
• Tapered mummy shape is thermally efficient
• It opens into a blanket

Cons:

• Expensive

Our testers agree that the Feathered Friends Flicker UL Quilt Sleeping Bag – 20 Degree can be used comfortably throughout a wider range of temperatures than any other sleeping bag on this list, prompting us to name it the best hoodless sleeping bag for fastpacking.

As this sleeping bag is hoodless, it is designed to be used with a hooded jacket or warm hat. Its full-length zipper and drawstring footbox closure provide ample venting options. This bag can even be opened up into a blanket for warmer nights. It is also astonishingly light and packable, stuffed full of 14.7 ounces of 950-plus fill down and weighing only 25.8 ounces in a size regular on our scale.

We found this sleeping bag warmest and most comfortable if we kept the zipper underneath the body. In this orientation, we could unzip the bag to just below the hip, effectively using it as a quilt. This was comfortable and warm between about 27 and 45 degrees Fahrenheit.

Below about 25 degrees Fahrenheit, we’d recommend zipping up the sleeping bag all the way but keeping the zipper under the body because, even though it has a draft tube, zippers tend to be a cold spot in most bags. This zipper’s low profile makes it virtually imperceptible when laying on it.

When fully zipped, the shape is mummy-like for thermal efficiency, snugging around the legs. The Enlightened Equipment Convert Sleeping Quilt – 20 Degree, reviewed below, by contrast, is more egg-shaped, a probable reason it wasn’t as warm as this sleeping bag.

We really only had one gripe about this sleeping bag. The neck cinch features two shock cord drawstrings — one on each side — that are adjusted by cinching a small cord lock. Unfortunately, these cord locks are insufficient for holding the neck opening closed, and even small movements uncinch the opening. We added an additional cord lock to each shock cord to remediate this issue.

The Feathered Friends Flicker UL Quilt Sleeping Bag – 20 Degree has truly outstanding versatility, making it our recommendation for anyone wanting only one sleeping bag. It’s cozy well into the teens, super light for its warmness, vents easily, and can be draped blanket-style for warmer nights.

You can get this sleeping bag in 20-, 30-, and 40-degree Fahrenheit options, so there’s something for any type of fastpacker.

Be sure to read our in-depth Feathered Friends Flicker UL Quilt Sleeping Bag – 20 Degree review, too!

Type: Hoodless Sleeping Bag/Quilt | Advertised Weight: 25.2 ounces (715 grams) in size regular | Actual Weight: 25.8 ounces (731 grams) | Fill Weight: 14.7 ounces (417 grams) of 950-plus fill | Temperature Rating: 20 degrees Fahrenheit | Packed Size: 7 x 13 inches (17.8 x 33 centimeters), 8 liters

Shop the Feathered Friends Flicker UL Quilt Sleeping Bag - 20 Degree

Best Ultralight Sleeping Bag without a Hood – Runner-Up: Zpacks 20F Full Zip Sleeping Bag ($519)

Pros:

• Very light
• Durable #5 coil zipper

Cons:

• Expensive for no differential cut
• 7-denier shell material less downproof than others we tested

The Zpacks 20F Full Zip Sleeping Bag is a high-end quilt/sleeping bag hybrid that would be virtually perfect if it had a differential cut.

Weighing only 21.4 ounces in size regular, this is the second lightest bag on our list, right behind the Feathered Friends Tanager CFL 20 Sleeping Bag, reviewed below. It is constructed from premium materials, including 13.7 ounces of 900 fill DownTek goose down and 0.51 ounce/square yard, 7-denier liner, and shell fabrics. The fabrics are thin and light, allowing the down to loft fully. The shell is also so thin it’s scary but is constructed with a tiny ripstop woven throughout, providing some peace of mind. Unfortunately, this material has proven to be the least downproof on any bag we tested, with little feathers leaking through here and there.

The bag has a long, two-way zipper, so you can open it nearly all the way on warm nights and zip it closed during the chillier times of the year. The neck opening cinches closed with a very thin shock cord, stretchy enough not to feel constrictive around the neck. And the collar clasp is a plastic wafer clip instead of the snap most companies use, a move we can get behind because it’s secure and easy to use.

So now you might be wondering what on earth could be wrong with this sleeping bag. In our opinion, it’s a little overpriced for what it is, especially when compared to the Feathered Friends Flicker UL Quilt Sleeping Bag – 20 Degree, reviewed above. The Feathered Friends bag has more high-quality down — 14.7 ounces of 950-plus fill versus Zpacks’s 13.7 ounces of 900 fill — and is constructed with a differential cut while being only $10 more expensive.

The lack of the differential cut was why we weren’t completely happy with this option. In short, bags with a differential cut are constructed with the shell cut a couple of inches wider than the liner and are capable of lofting fully even when elbows, knees, and shoulders are pressing into the liner. We expect premium quilts with high price points to come with this feature. But, if they added a differential cut to the Zpacks 20F Full Zip Sleeping Bag, the price could be justified, and it would really start to compete with our top picks.

Type: Hoodless Sleeping Bag | Advertised Weight: 21 ounces (595 grams) in size standard/medium | Actual Weight: 21.4 ounces (606 grams) | Fill Weight: 13.7 ounces (388 grams) 900 fill water-repellent down | Temperature Rating: 20 degrees Fahrenheit | Packed Size: 6 x 12 inches (15 x 30 centimeters) 7.1 liters

Shop the Zpacks 20F Full Zip Sleeping Bag

Lightest Ultralight Sleeping Bag: Feathered Friends Tanager 20 CFL Sleeping Bag ($469)

Pros:

• Crazy light
• Excellent warmth-to-weight ratio
• Tapered mummy shape is thermally efficient
• Tiny packed size

Cons:

• Pulling a sleeping bag on like a sock isn’t for everyone
• Minimal venting options

One of our testers has used the Feathered Friends Tanager 20 CFL Sleeping Bag as his go-to fastpacking sleeping bag for over a year, primarily because of its impressive warmth-to-weight ratio. For only 20.2 ounces in the 74-inch length, you get a bag stuffed with 13.3 ounces of 950-plus fill down that can take you to 20 degrees Fahrenheit or lower comfortably. As a bonus, this is the lightest sleeping bag we’ve included in this buyer’s guide.

Feathered Friends gave this bag a 5- x 7-denier nylon shell to save weight. This shell is scary light in appearance and feel but has held up to stuffing, unstuffing, and the unavoidable claws of a dog just fine. It’s also far more downproof than any other seven-denier shell material we’ve come across.

Being a zipperless, tube-style sleeping bag, it is not for everyone. The claustrophobic among us might shudder at the idea of sliding a sleeping bag on like a sock. The 62-inch shoulder girth was comfortable and thermally efficient for our slim to average male testers but a little wide for our smaller female testers — unless they were layering with additional clothing, in which case this bag worked well.

This bag has a pretty extreme taper, so the leg area is narrow. We found this somewhat uncomfortable after long days when our joints felt tight and our legs wanted to bend and stretch. On the other hand, we were grateful for the efficient cut of this bag during colder nights because the down wrapped warmly around our legs.

The upper end of this bag’s comfort zone is probably about 45 degrees Fahrenheit when we just leave the neck opening completely uncinched. One of our testers slept this way three nights in a row during a fastpacking trip through the mountains and deserts of central Arizona. If you want a bag to be comfortable throughout a greater range of temperatures, look at a sleeping bag with better venting options, such as the Feathered Friends Flicker UL Quilt Sleeping Bag – 20 Degree, which is about as warm but will also be comfortable in warmer temperatures in blanket mode.

In our experience, the lower end of this bag’s comfort is about 14F when wearing base layers and a down hood and sleeping on an insulated pad. Given that this bag is the lightest on our list, this is very impressive.

Type: Hoodless Zipperless Sleeping Bag | Advertised Weight: 19.7 ounces (558 grams) in size regular | Actual Weight: 20.2 ounces (573 grams) | Fill Weight: 13.3 (377 grams) ounces of 950-plus fill | Temperature Rating: 20 degrees Fahrenheit | Packed Size: 5.5 x 11 inches (14 x 28 centimeters), 6 liters

Shop the Feathered Friends Tanager 20 CFL Sleeping Bag

Best Ultralight Quilt: Katabatic Gear Alsek 22F Quilt ($430)

Pros:

• Very light
• Comfortable
• Tapered mummy shape is thermally efficient
• Adjustable shoulder girth
• Small packed size

Cons:

• Fiddling with sleeping pad attachment straps isn’t for everyone

The Katabatic Gear Alsek 22F Quilt is an amazingly light and warm quilt with well-thought-out features. It weighs a total of 23.7 ounces in a size regular and is packed with 14.1 ounces of 900 fill goose down. It also has the most secure sleeping pad attachment system we’ve seen on any quilt.

While an older version of this quilt was a little too narrow for one of our testers, Katabatic Gear has revamped this version with wider dimensions to increase comfort and reduce the possibility of drafts. Narrower quilts, by default, are more prone to drafts. This quilt used to have a shoulder circumference of 52 inches and has been widened to 54 inches. This may not sound like a lot, but it’s enough to make a difference for our 5-foot, 11-inch and 155-pound tester.

Several sleeping bags in our list suffer from inherent inflexibility due to their shape and size, often fitting certain bodies and not others. Because this one has an adjustable girth, we found it to fit a wider array of bodies better than any other sleeping bag on this list, from very narrow-shouldered to very broad-shouldered people. Indeed, it can be narrowed to only 54 inches and widened to an effective width of around 66 inches while still sealing in body heat.

While all zipperless quilts are prone to being drafty, this one reduces the risk with several unique design features. This quilt’s differential cut gives it a permanent tube shape rather than a blanket shape, so it always looks like it wants to hug you. The elastic-hemmed edges seem biased to snug under the body rather than spill out over the edges of your pad. And the pad attachment system utilizes a static cord, so it doesn’t stretch when you toss and turn at night. We had no issues with drafts when using this bag.

We have nothing but good things to say about the updated version of this quilt. It is warm and comfortable throughout a vast range of temperatures and can be adjusted both for climate control and to fit different body sizes.

Type: Quilt | Advertised Weight: 22.2 ounces (629 grams) in size regular | Actual Weight: 23.7 ounces (671 grams) | Fill Weight: 14.1 ounces (400 grams) of 900 fill | Temperature Rating: 22 degrees Fahrenheit | Packed Size: 6.5 x 11.5 inches (16.5 x 29.2 centimeters), 6.5 liters

Shop the Katabatic Gear Alsek 22F Quilt

Best Ultralight Quilt – Runner-Up: Enlightened Equipment Convert Sleeping Quilt – 20 Degree ($400)

Pros:

• Inexpensive
• Warm
• Comfortable

Cons:

• Egg shape is less thermally efficient

The Enlightened Equipment Convert Sleeping Quilt – 20 Degree is a very comfortable, reasonably priced, and versatile quilt. The stock model is constructed with a 10-denier shell and liner. The size regular/regular is stuffed full of 17.9-ounce, 850-fill water-repellent goose down and weighs 27.2 ounces. This same quilt also comes in a 950-fill option and can be purchased with temperature ratings from 0 degrees to 50-degrees Fahrenheit. We chose the 20-degree rating and down quality that would most closely compare to the other quilts on our list.

This is one of only two sleeping bags on this list with a drawstring footbox closure — the Feathered Friends Flicker 20 Quilt Sleeping Bag – 20 Degree, reviewed above, being the other. These quilts can be fully opened into blankets for warmer nights or cinched and zipped closed for colder nights. On warmer nights, you can unzip this quilt completely and just drape it over your body, allowing cool air around your feet or body.

The foot cinch doesn’t close as securely as the cinch on the Feathered Friends Flicker UL Quilt Sleeping Bag – 20 Degree and is the possible culprit for the cold feet one of our testers experienced during one 20-degree Fahrenheit night in the Wasatch Mountains in early May. Because the fully open bag is more or less rectangular, it transforms into an egg-shaped, rather than mummy-shaped, tube when zipped. This leaves a lot of room around the legs. A few of our testers enjoyed the extra space, but others wished the bag was more mummy-shaped to provide more thermal efficiency.

The sleeping pad attachment straps are stretchy, which we found less effective than the static cord attachments on the Katabatic Gear Alsek 22F Quilt. On the other hand, the wafer clips are easier to use than the little cord lock system on the Katabatic Gear quilt.

The shell and liner materials are worrying, in appearance at least — they don’t have ripstop. While they feel thicker than the seven-denier fabrics on the Zpacks 20F Full Zip Sleeping Bag or the Feathered Friends Tanager CFL 20 Sleeping Bag and could theoretically be more downproof, they probably won’t deal as well with dog claws or general abuse. If a tear begins, it will only get bigger over time. Only time will tell if this is a real issue, but our testers preferred the look and feel of some of the fabrics on other bags that got our highest ratings.

Lastly, this quilt is not constructed with a differential cut but is acceptable because of the reasonable price.

All in all, this sleeping bag is a solid choice for those wanting a sleeping bag/quilt hybrid that will perform well between 20 and 60 degrees Fahrenheit. If you want versatility and don’t want to spend extra money on the premium features of our higher-rated bags, definitely check it out.

Type: Hoodless Sleeping Bag/Quilt | Advertised Weight: 26.5 ounces (750 grams) in size regular/regular | Actual Weight: 27.2 ounces (772 grams) | Fill Weight: 17.9 ounces (507 grams) 850 fill water-repellent down | Temperature Rating: 20 degrees Fahrenheit | Packed Size: 6.5 x 12 inches (16.5 x 30.5 centimeters) 8.3 liters

Shop the Enlightened Equipment Convert Sleeping Quilt - 20 Degree

Best Budget Ultralight Quilt: Outdoor Vitals StormLoft Down TopQuilt 15 ($315)

Pros:

• Inexpensive
• Warm

Cons:

• Ineffective sleeping pad attachment straps and flimsy clips

The Outdoor Vitals StormLoft Down TopQuilt 15 made our list primarily because of its reasonable price tag of $315. This quilt is moderately light at 24.5 ounces, is constructed from decent materials, including 10-denier shell and liner fabrics, and is stuffed with 15 ounces of 800-fill water-repellent duck down. This is an excellent option if you’re just starting fastpacking and want a quilt that provides great value for the cost.

We chose this quilt with a temperature rating of 15 degrees Fahrenheit but were skeptical that this rating was realistic. With 15 ounces of water-resistant 800-fill duck down inside, this quilt is not quite as warm as other bags with similar amounts of a higher grade of down. For example, the Feathered Friends Flicker UL Quilt Sleeping Bag – 20 Degree has 14.7 ounces of 950-plus-fill down and is much loftier and warmer. That’s all right with us, though, as this quilt has an incredible price tag!

This quilt’s legs and footbox appear loftier than the torso area, which isn’t necessarily bad because it’s easier to add an extra layer to your upper body than your legs if need be. One of our testers got chilly in the high desert when temperatures plunged unexpectedly to the high 30s after a storm passed, but she warmed up after putting on her down puffy jacket. Other testers found the quilt plenty warm to about 35 degrees while wearing only base layers and a warm hat.

The quilt’s stretchy pad attachment straps don’t slide through the wafer clips easily, making them nearly impossible to adjust. Trying to adjust the straps, one of our testers broke a clip, rendering the quilt more susceptible to drafts during one cold night in the San Juans of Colorado. Fortunately, she could simply tuck the edge under her body and slept all night comfortably.

That said, don’t think twice about the shortcomings of this quilt if you can’t spend a ton of money on a premium quilt — it’s good enough for most situations. And sometimes — dare we say usually — good enough is all anyone ever needs. And given that the price of entry into fastpacking gear can be steep, we highly recommend this quilt to fastpacking-curious people.

Type: Quilt | Advertised Weight: 23 ounces (652 grams) in size regular | Actual Weight: 24.5 ounces (695 grams) with pad attachment straps | Fill Weight: 16.2 ounces (460 grams) of 800-fill water-repellent down | Temperature Rating: 15 degrees Fahrenheit | Packed Size: 7 x 12 inches (17.8 x 30.5 centimeters) 9.6 liters

Shop the Outdoor Vitals StormLoft Down TopQuilt 15

Comparing the Best Ultralight Sleeping Bags

SLEEPING BAG	PRICE	WEIGHT	TEMP RATING	PACKED SIZE
Feathered Friends Swallow UL 20/30 Sleeping Bag – 20 Degree	$629	27 ounces	20 degrees	7 x 12.5 inches
Montbell Seamless Down Hugger 800 #2	$429	22.7 ounces	25 degrees	5.9 x 11.8 inches
Feathered Friends Flicker UL Quilt Sleeping Bag – 20 Degree	$529	25.8 ounces	20 degrees	7 x 13 inches
Zpacks 20F Full Zip Sleeping Bag	$519	21.4 ounces	20 degrees	6 x 12 inches
Feathered Friends Tanager 20 CFL Sleeping Bag	$489	20.2 ounces	20 degrees	5.5 x 11 inches
Katabatic Gear Alsek 22F Quilt	$430	23.7 ounces	22 degrees	6.5 x 11.5 inches
Enlightened Equipment Convert Sleeping Quilt – 20 Degree	$400	27.2 ounces	20 degrees	6.5 x 12 inches
Outdoor Vitals StormLoft Down TopQuilt 15	$335	24.5 ounces	15 degrees	7 x 12 inches

Buyer’s Guide: How to Choose an Ultralight Sleeping Bag or Quilt

Types of Sleeping Bags

There are three primary types of ultralight sleeping bags, with some variation and crossover between the categories. In this list of some of the best ultralight sleeping bags, we’ve reviewed hoodless sleeping bags, like the Feathered Friends Flicker UL Quilt Sleeping Bag – 20 Degree, hooded sleeping bags, such as the Feathered Friends Swallow UL 20/30 Sleeping Bag – 20 Degree, and quilts, including the Katabatic Gear Alsek 22F Quilt. You’ll want to choose one of these based on your sleeping style, how you plan to use the rest of your gear in conjunction with your sleep system, and the types of trips you want to do.

We hesitate to say there is a best ultralight sleeping bag for back sleepers and one for side sleepers. Instead, we’ll just explain how each style is intended to work.

Hooded or Mummy Sleeping Bags

In general, hooded bags like the Montbell Seamless Down Hugger 800 #2  are meant to move with you as you toss and turn because your head remains in the hood. Regarding warmth, the main benefit of hooded bags is that they provide insulation for your head, meaning you don’t have to wear a beanie or hooded jacket inside.

The issue with this is if you want to use your hooded jacket or beanie as a part of your sleep system to save weight, you will face some redundancy issues. Some of our testers also like that hooded bags keep your pillow right where you want it.

Hoodless Sleeping Bags

Hoodless sleeping bags can either move with you or stay stationary because there is no fixed hood. These bags shine in part because they work with whatever layers you may want to bring along. If you plan to pack a hooded jacket on every trip, you can wear it inside your Feathered Friends Tanager 20  CFL Sleeping Bag, for example, effectively tacking a hood onto it. Fastpacking necessitates the implementation of multiple-use items for efficiency and weight savings, which is why many of us here at iRunFar like hoodless bags.

Quilt-Style Sleeping Bags

When listing the best ultralight sleeping bags, mentioning quilts such as the Katabatic Gear Alsek 22F Quilt is important. This style of sleep system is meant to remain fixed to a sleeping pad, with your body spinning rotisserie-style inside them. Like hoodless sleeping bags, they also work with hooded jackets to reduce gear redundancy.

But, in our opinion, the real benefits of quilts are threefold: First, they keep weight low by making a sleeping bag “bottomless,” effectively leaving out fabric and down that would normally wrap underneath the body. Second, they increase comfort by making the width of the bag adjustable. Third, they ensure that the top of the bag — the area where condensation and frost will land — never ends up underneath the body where the moisture would get pushed through the fabric into the down.

The main downside of a quilt is its susceptibility to drafts. Futzing with straps and cords can also be annoying, especially after a long day when all you want to do is sleep.

 Weight

We put a cap of 29 ounces for sleeping bags in this guide because fastpacking sleeping bags need to be light. In general, lighter sleeping bags will compress small enough to fit in a 25-liter pack and make running more enjoyable. The lightest bag on our list is the Feathered Friends Tanager 20  CFL Sleeping Bag, which weighs 20.2 ounces.

Choosing the best ultralight sleeping bag can’t just be light. It has to be warm, too.

Warmth

After narrowing our list to only bags under 29 ounces, we identified the ones with enough fill to theoretically be warm at or below about 25F on an insulated sleeping pad. In most cases, we were choosing 20-degree bags with between 12 and 16 ounces of fill depending on the grade, but some other claimed temperature ratings made it into the list. So, before even looking at cost or features, we had compiled a list of theoretically light and warm sleeping bags.

For the most part, that left us with pretty expensive bags such as the insanely warm Feathered Friends Swallow UL 20/30 Sleeping Bag – 20 Degree. Lighter bags, by default, use the highest quality down, which is one of the reasons they are more costly than heavier bags. Exceptions to this rule are the budget options we found, such as the Hammock Gear Economy Burrow — which we hope to test next year — and the Outdoor Vitals StormLoft Down TopQuilt 15, which got our budget award. This quilt uses mid-grade down and ultralight shell materials with minimal features and the simplest design. It’s also pretty warm.

Insulation Material

The two main types of insulation materials in sleeping bags are down and synthetic. Down comes from either ducks or geese. Synthetic insulation, such as Climashield Apex, is continuous filament insulation, meaning it is manufactured in large sheets and requires no quilting for construction. People choose synthetic-fill sleeping bags for exceptionally wet climates because they keep you warm even when damp. Some sleeping bags, such as the Katabatic Gear Alsek 22F Quilt, have different insulation material options.

A greater amount of synthetic insulation is generally required to achieve the same warmth as a high-grade down fill, so we didn’t test any synthetic sleeping bags. Synthetic insulation also doesn’t pack down quite as small as down and doesn’t spring back from compression as well, meaning it has a shorter lifespan.

Down Fill Power or Loft

Fill power measures the poofiness or lofting ability of goose or duck down, one of the main insulation materials in sleeping bags. Lofting can be thought of as the capability of down clusters to trap air. The higher the grade of down, the loftier it will be, and the more air — and thus body heat — it will trap.

Fill power is measured by placing 30 grams, or about one ounce of down, in a plexiglass cylinder and then placing a weight on top of it. Higher grades of down will compress less under the weight than lower grades.

To move this into a real-world example, this means that a sleeping bag with 15 ounces of 800-fill down will be less lofty and, therefore, less warm than a sleeping bag with 15 ounces of 950-plus-fill down. To reach the same loft and warmth as that 950-plus-fill sleeping bag, the one with 800 fill would need several more ounces of down, making it heavier.

The only downside to high-loft down is its high price tag. A bag like the Feathered Friends Tanager 20 CFL Sleeping Bag has 13.3 ounces of 950-plus-fill down.

When shopping for a sleeping bag, we recommend looking for a sleeping bag with as high a loft rating as your wallet can afford, as this means you’ll be getting a warmer sleeping experience at a lower weight.

Responsible Down Standard (RDS) Certification

Textile Exchange states, “The Responsible Down Standard (RDS) aims to ensure that down and feathers come from animals that have not been subjected to any unnecessary harm.” Every sleeping bag on this list uses RDS-certified down, and we wouldn’t have chosen any of them if they didn’t. The Katabatic Gear Alsek 22F Quilt comes with both goose-down and duck-down options.

Versatility

Versatility in fastpacking gear allows you to use single items in multiple conditions. The Feathered Friends Flicker UL Quilt Sleeping Bag – 20 Degree is probably the most versatile bag on this list because it is light and warm and can open at the foot or be used as a blanket in warmer weather. This can be nice if you only want to own one bag and know your trips will take you through mountains and deserts in all seasons.

Tube-style bags, like the Feathered Friends Tanager 20 CFL Sleeping Bag, can be less versatile than hoodless zippered bags or quilts because they have fewer venting options.

Durability

Many of this guide’s best ultralight sleeping bags are made with ultralight shell materials that sometimes appear scarily thin. The 7-denier shell on the Feathered Friends Tanager 20  CFL Sleeping Bag is an example of a shell material that should be treated with care. That said, not all shell materials are created equal, and it’s possible that the 7-denier shell on the Tanager could outlast 10-denier or 15-denier materials on some cheaper bags.

One of our testers has been using the Tanager very regularly for over a year, and it hasn’t abraded or leaked any down. On several occasions, a dog walked across it, leaving no evidence of her passing.

A different bag that did not make it into this list wasn’t so lucky, with the dog’s claws going right through the 10-denier material like butter. This bag’s main issue was a lack of ripstop within the fabric. Ripstop is a woven fabric with a grid of stronger reinforcement fibers to make it more resistant to ripping. Choose a sleeping bag fabric with a ripstop, no matter the denier.

Sleeping bag durability refers not just to the shell material but also to the quality of the down. Higher grades of down, such as the 950-plus fill found on the Feathered Friends sleeping bags, will generally continue lofting longer than the 800 fill found on the Outdoor Vitals StormLoft Down TopQuilt 15.

Zippers are another point of failure on a sleeping bag, as sand can work its way into the coil and either jam or wear down the sliders. In general, a larger coil will last longer than a smaller coil. We’d recommend sleeping bags with #5 coil zippers, like the  Zpacks 20F Full Zip Sleeping Bag, over bags with #3 zippers, such as the Enlightened Equipment Convert Sleeping Quilt – 20 Degree for this reason.

Packed Size

Every sleeping bag on this list is constructed with an ultralight shell, liner materials, and high-quality down for excellent packability. The smallest-packing sleeping bag on our list is the Feathered Friends Tanager 20 CFL Sleeping Bag, with a packed size of 5.5 x 11 inches. This bag takes up very little space, fitting easily inside even a tiny fastpacking pack such as the Pa’lante Packs Joey — read our Pa’Lante Packs Joey review.

Why You Should Trust Us

The iRunFar team has been fastpacking for over a decade, and we have watched this adventure niche grow. What started as two separate endeavors — ultralight backpacking and adventure running — have now merged into one, fastpacking.

For many of us, a good night’s rest is critical for making the next day’s miles possible. We frequently have no idea where we’ll end up for the night — parked on the edge of a snowfield at 13,000 feet or cowboy camping below the cold, cloudless firmament — so we want to haul along a sleeping bag that will perform wherever we lay down.

While a couple of fastpacking-appropriate sleeping bags have been in the iRunFar team’s personal rotation for a few years, this year, we set out to research dozens and test 15 of what we thought could be the best sleeping bags for three-season fastpacking and ultralight backpacking. We rated the bags on their warmth, shape, comfort, and weight, looking carefully at the quality and quantity of the down in each.

We tested sleeping bags on adventures in Silverton, Colorado, the Wasatch Mountains of northern Utah, the Mazatzal Mountains of central Arizona, and various locations throughout the canyon country of the Colorado Plateau. A team of fastpackers with a huge diversity of body types put these ultralight sleeping bags to the test in a range of temperatures and environmental conditions to help you decide what bag will work best for you.

Please note that product models are routinely discontinued in the outdoor equipment world, while new ones frequently come to market. At the same time, we here at iRunFar often keep using our top picks in our daily running … they’re our top picks, after all! Sometimes, that continued use results in uncovering product failures. With all this — product discontinuations, product introductions, and product failures — in mind, we routinely update our buyer’s guides based on past and ongoing testing and research by our authors and editorial team. While these updates can appear to be us pushing the newest product, it’s anything but that. When we update any buyer’s guide, most products will likely remain the same. That matches our goal: to get you in the best gear you’ll use for a long time.

Frequently Asked Questions about Ultralight Sleeping Bags and Quilts

What fill power is best for a fastpacking sleeping bag?

This is one of the very few areas where there’s a pretty simple answer that doesn’t require much nuance. Higher fill-power sleeping bags, like the Feathered Friends Swallow UL 20/30 Sleeping Bag – 20 Degree, are lighter, will be warmer for the weight, and will last longer than lower fill-power sleeping bags. The only downside is the cost.

In our opinion, however, this is one area where we’d recommend plunking down some cash. A good sleeping bag filled with quality down will easily last 20 years if you take care of it. The Feathered Friends sleeping bags use the highest grade down of any on our list.

How should my sleeping bag or quilt fit?

Fit is somewhat subjective so we won’t give you any absolutes here. But keep in mind when shopping for a fastpacking sleeping bag that narrower bags will generally be more thermally efficient, meaning they’ll be warmer for the weight than wider sleeping bags. Wider sleeping bags create a lot of air space between your body and the bag, which can sometimes be difficult to warm up.

If you know, you just can’t stand narrowness and would prefer wider bags for comfort, look at quilts because the shoulder circumference is adjustable. The shoulder girth of the Katabatic Gear Alsek 22F Quilt can be widened to a measurement of around 66 inches and also narrowed to 54 inches. Additionally, you can buy most sleeping bags on this list in different widths and lengths.

Do I need water-resistant down?

Some of the sleeping bags on our list, including the Outdoor Vitals StormLoft Down TopQuilt 15, have hydrophobic or water-repellent down. This means the down clusters have been treated with a durable water-repellent (DWR) chemical coating. Third-party tests show that this treatment indeed increases the down’s water resistance. What’s unclear is how long this treatment will last or if it affects the long-term lofting ability of down.

Some major brands, such as Western Mountaineering and Feathered Friends, still haven’t used treated down. But if you want extra peace of mind during fastpacking adventures in a wet climate, choosing a bag with hydrophobic down probably couldn’t hurt.

These are expensive! Do I really need to spend $400 or more on a sleeping bag?

The four most expensive items in a fastpacking kit are your fastpack, sleeping pad, tent, and sleeping bag. Excellent budget options are available in every category except sleeping bags. You can find $150 packs, $50 pads, and $100 tarps, but sleeping bags are different. The cheapest bag on our list is still $335!

But because a high-quality sleeping bag can last 20 years, we recommend saving for a good one. With this in mind, we chose our top pick, the Feathered Friends Flicker UL Quilt Sleeping Bag – 20 Degree. At $529, it’s expensive, no doubt, but if you take care of it, it will continue performing well for you in virtually any fastpacking scenario for at least two decades. Think about it: if a $500 sleeping bag makes it 20 years, that’s only $25 a year.

Should my sleeping bag be constructed with a differential cut?

Most high-end sleeping bags and quilts are constructed with a differential cut, meaning the inside is smaller than the outside of the bag. This makes it more difficult for a jutting elbow or a knee to compress the insulation and thus prevents cold spots. Constructing a bag with a differential cut is a little more time-consuming than just sewing two pieces of equally-sized fabric together, so these bags are usually more expensive.

That said, we don’t think it’s mandatory for a sleeping bag to have a differential cut. Lack thereof saves money, making bags like the Outdoor Vitals StormLoft Down TopQuilt 15 available to more people. And in our experience, the bags in this list without a differential cut are still very warm.

Should I get a down or synthetic sleeping bag?

High-quality down sleeping bags are warmer for the weight than similarly rated synthetic sleeping bags, prompting us to choose them for most fastpacking trips. Down insulation also compresses smaller than synthetic insulation and bounces back from compression better than synthetic, giving it a longer lifespan. The main benefit of synthetic sleeping bags is that they remain warm even when wet. Some sleeping bags, such as the Outdoor Vitals StormLoft Down TopQuilt 15, have down that’s been treated with a water-repellent coating that helps keep them warmer when damp. People who try to avoid using animal products may also prefer to opt for a synthetic sleeping bag.

What is the difference between a sleeping bag and a quilt? Should I get a sleeping bag or a quilt?

The main difference is that sleeping bags fully encapsulate you, whereas quilts are open underneath your body. Choose a sleeping bag like the Feathered Friends Tanager 20  CFL Sleeping Bag if you want it to move with you when you toss and turn. Choose a quilt like the Katabatic Gear Alsek 22F Quilt if you want it to remain fixed to your sleeping pad as your body spins inside of it.

Quilts save weight by losing the zipper and the material that would normally be underneath the body. They also are adjustable in width, widening for comfort and snugging in close for thermal efficiency. This adjustability also means that a single quilt could fit a range of body shapes and sizes.

One downside of quilts is that they can suffer from drafts. The cordage or webbing used to affix them to your sleeping pad can be a pain to fiddle with, especially when you’re tired and cold.

For those reasons, we recommend sleeping bags for those who don’t want to put much thought into setting up their sleep system. You just get in it and pass out. Quilts have a bit of a learning curve.

I sleep cold at night. Which sleeping bag should I get?

Instead of looking at temperature ratings, note how much down is in each sleeping bag you’re trying to choose between. For example, the Feathered Friends Swallow UL 20/30 Sleeping Bag – 20 Degree has 16.8 ounces of 950-plus fill rated at 20F. The Outdoor Vitals StormLoft Down TopQuilt 15 has a lower claimed rating — 15 degrees Fahrenheit — but has less down and a lower grade of down. In this case, the Swallow will be a far warmer bag than the StormLoft. Our testing proved this, with all testers agreeing that the Swallow was the warmest bag we tried.

I sleep hot at night, so which sleeping bag should I get? Are quilts for hot sleepers?

Most sleeping bags on our list can be ordered in different temperature ratings. Our top pick, the Feathered Friends Flicker UL Quilt Sleeping Bag – 20 Degree, can also be ordered in 30- or 40-degree ratings for those who sleep hot.

If you sleep hot at night, we would recommend getting a sleeping bag or quilt with a full-length zipper and a drawstring footbox, such as the Feathered Friends Flicker UL Quilt Sleeping Bag – 20 Degree or the Enlightened Equipment Convert Sleeping Quilt – 20 Degree. These bags provide more venting options than any others on our list. You can uncinch the drawstring and poke your feet out or unzip the entire thing and drape it over you like a blanket if you get too hot.

Some quilts are better for hot sleepers than others. The Katabatic Gear Alsek 22F Quilt doesn’t vent as well as the Feathered Friends Flicker UL Quilt Sleeping Bag – 20 Degree because it doesn’t unzip all the way or open at the feet.

My feet get cold at night, so which sleeping bag would be best for me?

Many people struggle with cold feet at night, even if they bring a second set of warm socks for sleeping. Cold feet can ruin an excellent night of camping in a hurry. If you can maintain a warm core but still have numb feet, the best ultralight sleeping bag for you probably isn’t a quilt or sleeping bag with a zipper down to the feet, like the Enlightened Equipment Convert Sleeping Quilt – 20 Degree. You’ll probably want to aim for a bag like Feathered Friends Swallow UL 20/30 Sleeping Bag – 20 Degree that completely protects your feet from the elements.

How should I take care of my sleeping bag? How do I wash my sleeping bag?

Sleep in base layers or a sleeping bag liner to prevent skin oils from soaking into the sleeping bag and degrading the down.

Don’t leave your sleeping bag compressed longer than you need to. Too much compression can reduce the lofting ability of down.

Store your sleeping bag hanging or in a large, breathable storage bag where it can loft as much as possible. If you plan to hang your sleeping bag, do so in a closet with a door that closes. Cats love to climb sleeping bags, as one of our testers has tragically discovered.

Wash your sleeping bag by hand or in a front-loading washer on a gentle cycle. Use soap made for washing down-filled items, such as Nikwax Down Wash Direct. Rinse at least twice to make sure all the soap is gone. Set the drier to low and tumble it with three tennis balls to break up clumping down clusters.

With proper care, a high-end sleeping bag like the Feathered Friends Flicker UL Quilt Sleeping Bag – 20 Degree can last very long. Investing in the best ultralight sleeping bag that your budget allows for can make it worth it.

I ripped a hole in my sleeping bag. What do I do?

We recommend carrying stick-on patches on your fastpacking trips to field-repair sleeping bag holes. A single sheet of Tear Aid Type A should be plenty. First, cut the patch to cover the tear completely and round the corners so it won’t peel. Then, clean any dirt away from the tear with water or alcohol and let it dry completely. Peel the backing from the patch and press it firmly over the tear.

A Tear Aid patch could last a long time but may not make it through several laundry cycles. If the tear is large, contact the manufacturer to see if they will sew a more permanent patch over the tear before laundering.

A sleeping bag like the Outdoor Vitals StormLoft Down TopQuilt 15, with its 10-denier liner and shell, will be more resistant to tears and scuffs than some extremely ultralight bags.

Why didn’t you test my favorite fastpacking sleeping bag?

We’d love to test everything out there, and in fact, we have a huge list of sleeping bags we hope to test in the future. If your favorite sleeping bag or quilt didn’t make it in our buyer’s guide, let us know about it in the comments and why you chose it over all the other options on the market! For now, we’ll stand behind our choices for the best ultralight sleeping bag, the Feathered Friends Flicker UL Quilt Sleeping Bag – 20 Degree.

Call for Comments

• Do you prefer sleeping bags or quilts?
• How low have you pushed a 20-degree sleeping bag?
• What’s your favorite layering system for sleeping?

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