The 8 Best Sleeping Bag Liners of 2023

We independently research, test, review, and recommend the best products—learn more about our process. If you buy something through our links, we may earn a commission.

TripSavvy's Picks

We like the Sea to Summit Thermolite Reactor Sleeping Bag Liner as the best all-purpose sleeping bag liner. It’s warm enough to add at least 10 degrees to your sleeping bag or to use on its own in warmer weather, comfortable to sleep in for most shapes and sizes, lightweight to carry, and generally the best bang for your buck. The Vumos Sleeping Bag Liner is our top budget pick.

Sleeping bag liners are among the best nice-to-haves in your camping or traveling kit. They’re excellent inside a sleeping bag in the winter to bulk up the bag’s warmth rating and keep it clean, so you don’t have to wash and wear it down as fast. You can also sleep inside one in lieu of a down bag on warm summer nights. They’re great to take along when traveling if you’re sleeping on trains or want a hygienic barrier between yourself and hostel sheets. The best sleeping bag liner depends entirely on what you’ll be using it for, but we’ve delved deep to narrow down the best sleeping bag liners for every situation.

Best Overall

Sea to Summit Thermolite Reactor Insulated Sleeping Bag Liner

Sea to Summit Reactor Insulated Sleeping Bag Liner

Amazon

What We Like
  • Affordable compared to other top models

  • Excellent warmth-to-weight ratio

  • Stuffs down small for travel

  • Drawcord hood, stretchy material, and tall enough for people up to 6-feet, 5-inches

What We Don't Like
  • Probably not warm enough for extreme temps

Sea to Summit's Thermolite Reactor is our top pick for a sleeping bag liner, because it's got the best warmth-to-weight ratio on the market, thanks to proprietary hollow-core fibers that allow for better breathability and less weight. It adds a realistic 10 to 15 degrees F of warmth to your bag (though the company claims 25 degrees), which is enough to make a huge difference when using a summer sleeping bag in the cold or on its own during hot nights. It's light, at just 8.1 ounces, and stuffs down in the included stuff sack to be shorter and slightly stouter than a Nalgene water bottle.

The mummy shape will comfortably fit into a similarly shaped sleeping bag. This liner is thin and made of polyester, but it's knitted rather than woven, allowing it to be stretchy and not constrict as you toss and turn in the night. We also love Sea to Summit's attention to small bonus features, like a colored and slightly stiff hood edge so you can easily see where the top is when you're trying to get into it, a drawcord on the hood to cocoon yourself even deeper into your bag, and a zipper for easy entry.

It also comes in a long version for folks taller than 6-feet, 5-inches.

Price at time of publish: $90

Size: 82 x 35 inches | Weight: 8.1 ounces

Best Budget

Vumos Sleeping Bag Liner

Vumos Sleeping Bag Liner

Amazon

What We Like
  • Very affordable

  • Packs down small

  • Stuff sack included

  • Unzips fully and has a pillow pocket

What We Don't Like
  • Doesn’t add too much warmth

  • Cheap stitching and hardware won't last a long time

  • Not super-lightweight

The Vumos Sleeping Bag Liner will help keep your sleeping bag cleaner and may provide you with a few extra degrees of warmth without breaking the bank. It features 100 percent polyester, so it's breathable and relatively lightweight to pack. This liner has a zipper—which is a bit clunky—that runs down the side and the bottom, making it easy to get into and out of and double as one large sheet unzipped. It also has a pillow pocket, which we love for keeping your face off a questionable hotel pillow when traveling, or your dirty face off your clean pillow when camping.

It also comes with a stuff sack and can pack down to be about the size of a pair of wool socks, which is ideal. It's not as lightweight, warm, or well-made as more expensive liners, but it'll definitely do the trick if you're just looking for something for infrequent use. And if you don't like the looks of the Vumos liner, the Tough Outdoors XL Sleeping Bag Liner is another solid budget pick.

Price at time of publish: $29

Size: 85 x 33.5 inches | Weight: 11.5 ounces

Best Silk

Cocoon Silk Mummy Liner

Cocoon Silk Mummy Liner

REI

What We Like
  • Warm

  • Incredibly lightweight

  • Ripstop silk is more durable, and it's easy to hand-wash

What We Don't Like
  • More delicate than other materials, especially if you machine wash

  • Can be hard to climb into and out of with no zipper

Silk liners are the cream of the crop for a three-season liner, because they’re insulating, soft to the touch, and super-lightweight. They pack down small and don’t get tangled up at your feet (although they do tear more easily than other materials).

There are a lot of good silk liners out there, but Cocoon’s Silk Mummy Liner takes the cake for being affordable while still being lightweight (just 4.96 ounces) and featuring ripstop materials and some attractive bonus features.

The 100 percent ripstop silk will help keep you cool in the summer and warm in the fall or winter (adding about 7 to 8 degrees of warmth). It’s more durable and less prone to tearing than regular silk. This liner has a hood to keep the bag from slipping down in the night, and we love that silk is easy to hand-wash for when you’re on the trail or traveling.

Other silk options we like are the Sea to Summit Premium Silk Traveller Liner and Western Mountaineering Tioga Silk Sleeping Bag Liner.

Price at time of publish: $80

Size: 95 x 35 inches | Weight: 4.96 ounces

Best for Extreme Cold

Litume All Season Sleeping Bag Liner

Litume All Season Sleeping Bag Liner

Amazon

What We Like
  • Adds almost 30 degrees of extra warmth

  • Drawstring hood

  • Half-zip or no-zipper options available

  • Comes with a waterproof compression sack

What We Don't Like
  • Heavy for anything but car camping

From Taiwanese outdoor brand Litume, this sleeping bag liner features soft fleece and adds a whopping 20 to 27 degrees of warmth to your sleeping bag, which is hard to come by and ideal for beefing up your sleeping bag during hunting season or winter camping. We love that that’s also warm enough to use without an outer bag during warm summer months. The liner also has a drawstring hood to really wrap yourself in, and you can opt for a half zip or no zipper.

The stuff compression sack is waterproof so that you can tie it onto the outside of your backpack, and it is only about the size of a Nalgene. It does weigh just over a pound, which is heavy for something like backpacking but still lightweight, considering the amount of insulation you’re getting. We also like the Sea to Summit Thermolite Reactor Fleece Liner for extreme cold situations.

Price at time of publish: $61

Size: 90 x 56 inches | Weight: 17.6 ounces

Best for Backpacking

Cocoon Silk Mummy Liner

Cocoon Silk Mummy Liner

REI

What We Like
  • Quick-drying and moisture-wicking fabric

  • Special insect-repellent shield

  • Lightweight

  • Packs down small

What We Don't Like
  • Won’t work as a winter liner

This liner made our list again, because it’s one of the lightest sleeping bag liners available and, compared to competitors (namely, the Sea to Summit Premium Silk Traveller Liner), it also packs down smaller, folds out to be bigger, and is easier to get back into the stuff sack.

The Cocoon Silk Mummy Liner features ripstop silk, so it’s incredibly lightweight (just 4.96 ounces) but more durable than other silks. It’s excellent at regulating temperature, which is ideal if you’re moving among different altitudes or backpacking in different climates regularly, and it will add about 7 to 8 degrees to your sleeping bag. You can easily hand-wash it while you’re in the backcountry.

Price at time of publish: $80

Size: 95 x 35 inches | Weight: 4.96 ounces

Best for Warm Weather

Sea to Summit Adaptor COOLMAX Mummy Sleeping Bag Liner with Insect Shield

Sea to Summit Coolmax Liner Insect Shield

 Courtesy of Amazon

What We Like
  • Quick-drying and moisture-wicking fabric

  • Special insect-repellent shield

  • Lightweight

  • Packs down small

What We Don't Like
  • Won’t work as a winter liner

You can certainly sleep with just a liner when it's warm enough out, and Sea to Summit's Adaptor Coolmax is ideal for all types of warm conditions. 

For starters, it features proprietary COOLMAX polyester—a moisture-wicking, quick-drying fabric with the softness of cotton ideal for humid climates. Then, it's infused with an EPA-registered, odorless insect repellent shield to keep those pesky summer bugs, like mosquitoes, ticks, and flies, away. That shield stays good for 40 washes, or around six months of exposure. 

This Mummy Shape has a drawcord hood to cinch in for a little extra warmth and a 3D foot-box to offer extra room at your feet. The same liner also comes in a Traveler's Shape, which includes a square bottom and pocket for your pillow. This liner also packs small (3x5 inches) in a lightweight stuff sack.

Size: 84 x 36 inches | Weight: 8.6 ounces

Best for Traveling

Tough Outdoors Sleeping Bag Liner

Tough Outdoors Sleeping Bag Liner

Amazon

What We Like
  • Price

  • Fully unzips for easy exit and doubles as a sheet

  • Pillow pocket

  • Lifetime warranty

What We Don't Like
  • Considered heavy for backpacking

  • Not the warmest as a sleeping bag liner

Made from soft polyester, this sleeping bag liner is lightweight and breathable, and it packs to the size of a book for convenient travel. We love this liner for traveling, because it has a full zipper (side and bottom), so it’s easy to get into and out of when sleeping on a train, in a car, or at an airport if need be, but you can fully unzip and butterfly the bag open to create a full-size sheet to lay on top of if you’re worried about the sanitation of a hotel or hostel bed. It also has a pocket to slide a pillow inside (or stuff a jacket in when there isn’t a pillow around), so your body and face can lie on something you trust is clean.

If you want to use it as a cheap sleeping bag liner, it’ll add a light oomph in keeping you warm at night (realistically, adding about an extra 5 degrees). Plus, for under $25, you won’t be mad if something happens to it while you’re traveling, although it’s worth noting that Tough Outdoors offers a no-questions-asked lifetime warranty.

Price at time of publish: $22

Size: 86.5 x 31.5 inches | Weight: 13.7 ounces

Best Merino Liner

Cocoon Merino Wool Mummy Liner

Cocoon Merino Wool Mummy Liner

REI

What We Like
  • Great thermoregulation

  • Wicks moisture away from the body

  • Soft wool

  • Fits tall people

What We Don't Like
  • Heavy

Merino wool liners are great for their ability to temperature regulate and their natural odor-absorbing, moisture-absorbing properties. But while most merino liners will run you well over $100, this option from Cocoon is well priced and well made.

The Cocoon Merino Wool Mummy Liner uses merino wool to offer breathability, moisture-wicking, and warmth retention. Air circulates in the natural hollow of the wool fibers, which helps moisture pull away to keep you cool and dry at night. This liner will add about 10 degrees of warmth inside your sleeping bag or keep you warm enough (thanks to that moisture pull) on a hot summer night when you just want a cover.

We especially love merino for outdoor pursuits, because it naturally resists odors—invaluable on your fifth day without a shower. And Cocoon’s wool is soft to the touch and not scratchy. The only real bummer of merino wool is the weight: This liner is 17.5 ounces, so you probably won’t be backpacking with it.

Price at time of publish: $100

Size: 86 x 32 inches | Weight: 17.5 ounces

What to Look for in a Sleeping Bag Liner

Material

Silk sleeping bag liners are generally the nicest but also the most delicate. Silk is super-breathable in warm weather but also insulates in the cold and doesn’t get tangled up in your clothes or around your feet. It’s also easy to wash, especially by hand, which makes it an excellent choice for travelers looking for a liner to use in hostel beds. However, silk can be prone to tears. Taking extra care in packing and washing or drying your silk liner can help extend its life.

Synthetic materials are lightweight to carry, good at retaining heat, and moisture-wicking, and breathable. Cotton is very breathable but also bulkier, so it’s not suitable for backpacking. It doesn’t wick moisture away, so if you’re sleeping somewhere humid or sweat a lot at night, it will not only hold your moisture in the layer but also potentially make you colder.

Fleece liners definitely add warmth, but if you move around a lot at night, the fleece can easily get tangled in your limbs. Some people love the feel of fleece, while others hate it. Merino wool liners, like most merino wool outdoor gear, are a great choice, because the material is lightweight, breathable, moisture-wicking, and odor-absorbing.

Heat Rating

Most bag liners add between 5 and 20 degrees F of warmth to your sleeping bag or hiking quilt.

Sleeping bag liners have temperature ratings to indicate how warm they’ll keep you, most often in the form of a plus symbol (+) followed by a number to indicate how many degrees it will add to your sleeping bag, unlike sleeping bags with specific temperature ratings.

Alternatively, liners sometimes use the older R-value system, which measures the liner’s ability to resist heat flow through it. Therefore, something with a higher R-value will insulate you better and keep you warmer.

Shape

A rectangle-shaped liner will give you more room in the bag; a mummy shape will keep you warmer as there is less air around your body, but some people have issues with the bottom taper getting tangled around their feet at night. If you’re tall, a taper mummy liner is often more comfortable.

Consider the shape and size of your bag. If you have a mummy-shaped sleeping bag that fits close to your height, you’ll likely want a mummy-shaped liner. A shorter rectangle can be comfortable if your bag is too big for you. If you have a rectangle sleeping bag or sleeping quilt, you can choose either a rectangle- or mummy-shaped liner. 

Breathability

As with most outdoor gear, breathable is always better, because it allows air to flow through to ensure you won’t overheat at night, which is especially important, since sweating inside a bag can make you colder as the moisture cools on your skin. However, you want a balance among breathable, moisture-wicking, and heat-retaining.

Weight

Some liners weigh more than others. Choosing a lightweight liner is definitely important if you’re backpacking, bikepacking, or traveling, but if you’re car camping, weight and packability aren’t that crucial.

Zipper

Whether you want a bag with a zipper is part personal preference, part situation. A bag without a zipper is harder to get into and out of, and you can’t unzip it if you’re too hot. However, going without a zipper can reduce the weight and bulk of the liner for backpacking or traveling, and some people find it more comfortable to be fully cocooned without the hardware.

Frequently Asked Questions
  • When and why should you use a sleeping bag liner?

    Sleeping bag liners are ideal for keeping you warmer while you camp. Specifically, adding a liner can help increase your sleeping bag's warmth, which is ideal if you usually camp somewhere warm or low-elevation with a sleeping bag rated for 32 degrees F or above, but you're going to take some trips to the high alpine or the desert in the fall and winter, where it can get below freezing at night. Instead of buying a new sleeping bag with a lower temperature rating, you can add a liner to insulate it another 5 to 20 degrees. Sleeping bag liners are also a great choice when you're backpacking, since the dirt and oils from your body can rub off onto your sleeping bag and make it less effective (in addition to gross and stinky). The liner acts like a sheet on your bed, allowing you to just wash that instead of the bulkier, technical outer bag. That also helps lengthen the lifespan of your sleeping bag.

  • Are sleeping bag liners also good for warm weather?

    Yes, you can also use a sleeping bag liner instead of a sleeping bag when you only need one thin layer over your body at night instead of a down bag.

  • How do you care for and wash a sleeping bag liner?

    Most sleeping bag liners are machine washable at home on gentle, including most silk liners. However, they will last longer if you hand-wash them (especially silk), and like all outdoor gear, they should be hung to dry and not put in the machine.

Why Trust TripSavvy

Rachael Schultz is a fitness and outdoor product journalist based in Carbondale, Colorado. Growing up in and around cities on the East Coast, she wasn't taught how to backpack or ski as a kid, which means that as she moved West, and her passion for the outdoors grew in adulthood, so did her research skills around what exactly one needed to buy to get outside. Now an avid mountain biker, skier, hiker, and camper, she's endlessly fascinated by, and knowledgeable about, the nuances among materials, performance, and convenience of outdoor gear. She's lucky enough to get to test everything from women's ski bibs to ultralight backpacking gear to camping cocktail kits. Rachael is passionate about making the outdoors just as accessible to those who haven't spent much time under the stars as those who grew up enjoying it, and that includes having the right gear to stay safe, happy, and motivated to head out again as soon as possible.

Was this page helpful?
Continue to 5 of 8 below.