Best Sleeping Bag Liner of 2021

A good sleeping bag liner can extend your sleeping bag's lifespan by years. In this post, you'll find expert advice on how to choose the best sleeping bag liner for your needs plus a selection of our top picks for 2021.

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Sleeping Bag Liners: Providing Added Warmth To Your Sleeping System

Looking for the best sleeping bag liner?

You’re in the right place! In this guide, we will be covering the following:

    • What is a sleeping bag liner?
    • Why you need one
    • What you should consider when buying
    • Sleeping bag liner reviews of the 5 best sleeping bag liners in 2021
    • Our unbiased recommendation on the #1 sleeping bag liner

The greatest challenge campers face on outdoor expeditions is getting a comfortable, good night’s sleep. 

While it’s almost impossible to get the same quality of sleep as in your bed at home, there are a few hacks hikers have come up with to stay warm and comfy throughout the nights in your tent. The best of them is, without any doubt, the sleeping bag liner. 

This lightweight addition to your camping kit can make a world of difference. Not only will it give your sleep setup a comfort boost, it will also contribute a few degrees of warmth to your sleeping bag and increase its lifespan by a good few years at a minimum.

In this article, we’ll explain what a sleeping bag liner is and delve into more detail on why you should consider buying one. We’ll also share a few of our favorite liners on the market in 2021 to help you choose the perfect model for your needs.

Whether you’re looking for a merino wool sleeping bag liner, a cozy fleece sleeping bag liner, a lightweight summer liner, or the warmest sleeping bag liner out there, our list has you covered!

Editors Choice

Cocoon Silk MummyLiner

Cocoon Silk MummyLiner (Natural, 95-Inch x 35/22-Inch)

The greatest attribute of Cocoon’s Silk Mummy Sleeping Bag Liner is its versatility. The MummyLiner’s silk fabric will serve you well whether you’re camping in cool or high temps, feels great against the skin, and is more durable than other silk-based competitors to boot.

Believe it or not, this silk mummy liner can add an impressive 9.5°F to your sleep setup. Given the MummyLiner’s incredible breathability, however, it also helps to keep you cool and sweat-free.

Since this product is made of silk, it’s lightweight and easy to pack into its stuff sack. Indeed, you’ll only add 4 ounces in weight to your backpack, making it the best backpacking sleeping bag liner for the gram-counting backpacker. Although it feels elegant and delicate, this MummyLiner is hard-wearing and will last you a lifetime with proper care.

Cocoon’s mummy bag liner strikes a great balance between value and quality. People who want a well-made silk liner at a reasonable price should place this one somewhere very near the top of their shortlist.

Runner Up

Sea to Summit Premium Silk

Sea to Summit Premium Silk Travel Liner (Pacific Blue, Mummy (82 x 36in))

The Sea to Summit Premium Silk is a lightweight, comfortable, moisture-wicking, quick-drying liner that combines a snug fit with materials that are far more trailworthy than those used in its competitors.

The type of silk used in the Sea to Summit Silk is AA Grade ripstop silk, one of the strongest in the industry. The manufacturers also included polyester and lycra side panels to make the liner even more flexible, which makes it a great pick for people out there who tend to move around a lot at night.

What we love most about this product is that it is available in a wide variety of sizes, shapes, and colors. So, no matter what you’re looking for, you should be able to find the perfect model for your needs.

Benefits & Features Of Sleeping Bag Liners

Why Use A Sleeping Bag Liner?

The primary reason to use a liner is to prevent sweat, body oils, and dirt from accumulating in your sleeping bag. Not only does this help to keep your expensive bag clean, it also significantly increases its lifespan. 

Using a liner also makes it much easier to do your post-trip laundry. Instead of the lengthy rigmarole of washing your sleeping bag, you can just pop your liner in the machine and your chores will be complete (those related to your bedtime setup, at least!).

man sitting outside tent in the snow in sleeping bag intext
Adding a liner is possibly the most cost-effective way of “upping” your sleeping bags cold weather rating

The second most obvious reason for including a liner in your pack is to keep you warm when camping in cold conditions. The extra warmth they provide can dramatically cut your risks of a chilly night and you’ll have a far easier time falling asleep. 

Many hiking, backpacking, and camping enthusiasts also use a liner because they add a little layer of protection between you and the shell material of your sleeping bag, thus improving next-to-skin comfort levels. 

RELATED: Best Backpacking Pillows

Another nice benefit liners offer is that they are easy to air out after you wake up. This will save you precious moments in the morning so you spend more time enjoying your surroundings. 

The last reason you should use a bag liner is to take advantage of the antimicrobial properties that some manufacturers add. Think of these liners as a natural form of bug repellant. With the added layer of your liner, you’ll dramatically reduce your risk of getting bitten by dangerous ticks and mosquitos. 

Indeed, many savvy budget travelers buy the best sleeping bag liners to protect themselves from bedbugs in hostels. Bugs should be a concern for all outdoor campers, and using a liner is an easy way to protect yourself.

The bottom line? This handy little accessory is one that can entirely transform your camping experience – and at relatively little extra cost in terms of both pack weight and $.

Set Your Priorities Before Shopping For Liners

Before we get into the advantages and disadvantages of different fabrics, it’s important to come up with your own list of priorities. 

Do you do your camping in warm weather and need a fabric that offers enhanced breathability? Or are you more of a cold-weather camper and looking for a bag liner to provide an extra 10, 15, or 25 degrees of warmth? Maybe you want a product that can handle both extremes? Knowing your personal needs, in short, will help you choose the ideal option. 

What’s The Best Fabric?

Firstly, here’s a simple rule all new campers must heed: cotton is c**p. We can’t stress this enough. While a cotton sleeping bag liner is likely to be more affordable, it will also take forever to dry when wet, doesn’t wick moisture nearly as well as other materials, and offers a poor warmth-to-weight ratio. 

Silk liners are the most lauded in the industry. Silk products are far easier to compress into stuff sacks, very lightweight, and feel pleasant to the touch. Liners made out of silk also have the best antimicrobial and antiparasitic properties and perform equally as well in hot and cool conditions. 

While they might not offer the same degree of warmth as some fleece or wool liners, silk products remain the most high-performing and durable in the industry. 

A step up from silk in the warmth department is a fleece sleeping bag liner. Most liners made out of this material can add at least 10°F to your sleeping bag. In contrast to silk, however, fleece sleeping bag liners tend to be heavier and more difficult to pack. They are also nowhere near as breathable as silk, so bear this in mind if you plan on camping in warmer locations.

sleep system sleeping pad bag in hammock
Photo by jchapiewsky / CC BY-SA 2.0

For the ultimate warmth at night, it’s worth taking a look into insulated liners. Many of the companies that make these liners say they can increase your sleeping bag temperature by as much as 25°F. 

Insulated liners are also able to dry off quickly thanks to their microfiber materials. Because of all the additional insulating material, however, these liners can be a bit tricky to pack and weigh more than other types of liners.

Lastly, people traveling to hot and humid areas should look into synthetic products. These liners were designed to repel moisture and offer enhanced breathability to help keep you cool when temps are high. Since most synthetic liners focus on moisture management rather than insulation, however, they aren’t the best option for hikers going into colder regions.

Sleeping Bag Liner Design

Sleeping bag liners are thin sheets of fabric that can either be placed inside your sleeping bag or used on their own. Almost every sleeping bag liner today is machine washable. 

The most common of sleeping bag liner shapes is the mummy design with a hood on top. Mummy designs are common because they best fit into most sleeping bags and provide extra protection and cushioning for your head. Most of these liners also have strings attached to them so you can tie the hood around your head for a snug fit and extra warmth. 

After mummy-shape designs, the most common camping bag liners are in a rectangular shape without a hood. It’s possible to place these rectangular liners in your sleeping bags as well, but campers typically buy this style for standalone use in warm weather.

RELATED: Best Winter Sleeping Bags

There’s no standardized opening for sleeping bag liners. Some have openings on the side with Velcro or zippers, but most have an opening on the top which you have to crawl or jump into. Because the side and bottom seams are sowed on liners with only a head opening, these products tend to provide better insulation.

Lastly, for those who prefer to double-up with their partner, then you have the option of buying two separate liners or using a double sleeping bag liner.

The Best Sleeping Bag Liners Reviewed

Sea to Summit Premium Silk

Sea to Summit Premium Silk Travel Liner (Pacific Blue, Mummy (82 x 36in))

Let’s begin with the number one selling point of this luxury item: it’s made out of AA Grade ripstop silk. In case you didn’t know, ripstop refers to a special kind of weaving technique that reinforces numerous threads to make fabrics more durable and resistant to tears and punctures. Although it’s strong, this silk fabric feels very soft against the skin.

In addition to high-quality silk, the manufacturers have included a few layers of polyester and lycra (aka spandex) seams on the sides. These fabrics help the liner stretch even further, which makes it ideal for those prone to tossing and turning in their sleep. 

This product is available in several different styles. Whether you want a longer rectangular shape, one with pillow inserts, or a mummy-shaped model, Sea to Summit have you covered!

The regular-sized rectangular model measures 73 inches high by 36 inches wide and weighs only 4.6 ounces, making it light enough for backpacking and big enough for larger sleepers. 

Not only do Sea to Summit liners come in a wide variety of sizes, they are also available in different colors. The four colors you can choose from include two shades of blue, green, and dark pink.

Due to its use of premium silk, this liner is a little on the pricey side. However, if you’re looking for a high-performing, rugged option that’s suitable for year-round use, you’ll be hard pressed to find a better option than this.

  • PROs

    • Fine AA grade ripstop silk is very durable.
    • Stretch panels on seams to help restless sleepers.
    • Wide variety of colors and designs to choose from.
  • CONs

    • Pricey
    • One of the shortest heights on our list

Bottom-Line: A high-performing, high-quality silk liner that’s as durable as they come and geared towards serious campers looking to make a once-in-a-lifetime purchase.

ALPS Mountaineering Microfiber Mummy

ALPS Mountaineering Brushed Polyester Mummy Sleeping Bag Liner

The ALPS Mountaineering Microfiber Mummy is a low-cost but extra-cozy fleece liner that’s ideal for buyers who don’t mind carrying a few extra ounces in weight in return for a lot of extra degrees in warmth. 

This product measures 86 inches in length and 32 inches in width and weighs 11 ounces. ALPS Mountaineering also makes a version in polyester-cotton.

As with most fleece liners, the ALPS MMM is a little on the heavy side and is also less packable. However, it makes up for these shortcomings with a friendly ticket price and a very user-friendly, well-thought-out design. While ALPS don’t state how much warmth this product adds to sleeping bags, our estimate is 10-15 degrees fahrenheit. 

Some of the endearing features found in this product include a Velcro strap on the top that you can use to open and close this product, two drawstrings that let you tighten the hood around your head, and double-stitched seams to prevent tears. 

A minor setback of this ALPS product is that it doesn’t have any special stretchy material. There is a good deal of room, but if you’re bigger and tend to roll around a lot at night then this might cause a few comfort issues.

  • PROs

    • Comfortable microfiber fabric provides good insulation 
    • Very long – great for tall campers
    • Limited lifetime warranty
  • CONs

    • A bit heavy and bulky
    • Not much “give” or stretch in the material

Bottom-Line: While it’s not as luxurious as silk, the ALPS Mountaineering Microfiber Mummy is an affordable and well-designed product that packs plenty of added warmth. 

Sea to Summit CoolMax Adaptor Insect Shield

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The Sea to Summit Coolmax is a high-quality, breathable, and brilliantly well-designed product that packs a special bonus feature that makes it an awesome choice for campers in warmer climates. 

The CoolMax Adaptor is made out of a special polyester and uses Sea to Summit’s CoolMax technology. In addition to enhanced breathability, CoolMax technology offers superior moisture-wicking capabilities to most other synthetic competitors and also dries very quickly.

But the key feature and unique selling point of the CoolMax Adaptor is that it includes a layer of odorless insect repellent that provides protection against mosquitoes, flies, and other airborne biters while you sleep. The insect repellant used in this product has been recognized by the EPA and will last at least six months or 25 cycles in a washing machine.

As for its dimensions, the Adaptor measures 82 inches long by 35 inches wide. And with the stuff sack included, it weighs just under 10 ounces. 

The materials used in this one are also nice and stretchy, so if you happen to move around a lot in your sleep, the Adaptor is a winner!

And the downsides? 

Well, this isn’t the warmest liner in our review by quite a large margin. However, given that it’s intended for use in warmer climates it’s hard to see this as an overly serious shortcoming. 

  • PROs

    • Excellent for hot and humid climates
    • Insect-repellent fabric
    • Weighs 9.3 ounces with stuff sack
    • Stretchy inserts for added mobility
  • CONs

    • Only available in one color and one size
    • Doesn’t add as much warmth as other options
    • Insect-repellent treatment wears off over time

Bottom-Line: The ideal pick for buyers who plan on doing their camping in warmer climates where plenty of bugs are likely to be on the prowl. 

Sea to Summit Reactor Thermolite

Sea to Summit Reactor Insulated Sleeping Bag Liner, Regular (83 x 35)

The Sea to Summit Reactor Thermolite is a great choice for buyers who plan on doing most of their camping in colder conditions.

In contrast to the CoolMax Adaptor, the Reactor Thermolite lining is designed to keep your sleep system toasty. Sea to Summit claim the Reactor Extreme Thermolite can increase your sleeping bag’s temperature rating by as much as 25°F. 

The reason it’s able to get this hot is thanks to the manufacturers’ trademarked Thermolite synthetic insulation, which uses your own body heat to generate added warmth while you sleep.

At 14 ounces, the Reactor Thermolite is the heaviest on our list by a good few ounces, but its 84” by 36” dimensions also make it one of the roomiest. It also packs down to a very backpack-friendly 4 x 6 inches. 

  • PROs

    • 110g/m2 Thermolite fabric can add up to 25°F to your sleep system.
    • Roomy design is great for restless sleepers.
    • Drawstrings and hood help increase already impressive insulation.
  • CONs

    • Not as breathable as others
    • The heaviest model on our list 

Bottom-Line: The best out there for people who are primarily concerned with maximizing the amount of warmth a liner brings to their sleeping bag and don’t mind adding a few extra ounces of weight to their pack.

Cocoon Silk MummyLiner

Cocoon Silk MummyLiner (Natural, 95-Inch x 35/22-Inch)

The Cocoon Silk MummyLiner is an extra-long, all-silk product that ticks the practicality and performance boxes better than any other we know of.

The MummyLiner measures a whopping 95 inches long by 35 inches wide and yet only weighs about 4 ounces. This makes it both the tallest and one of the lightest on our list. 

Bit it ain’t all about size. In fact, what really sets the MummyLiner apart is its versatility. In cooler areas, it can increase the temperature of sleeping bags by as much as 9.5°F, while in warmer conditions its outstanding breathability will ensure you stay cool and sweat-free. 

One nice feature about the Cocoon Silk MummyLiner is that it’s available in many different colors. Whether you want a plain understated color of a more flamboyant design, you should find a Cocoon to suit your fancy. 

  • PROs

    • Fine silk fabric
    • Weighs less than 5 ounces including stuff sack 
    • Can increase sleeping bag temperature by 9.5°F
    • Longest model on our list
    • Great warmth-to-weight ratio
  • CONs

    • No added fabrics to increase stretch

Bottom-Line: An ultralight sleeping bag liner that performs well in all weather conditions. What’s not to love? 

Rab Silk Sleeping Bag Liner

RAB 100% Silk Sleeping Bag Liner (Double) (Assorted)

The Rab Liner is an incredibly well-made, lightweight option that’s perfect for backpackers who are keen to cut down on pack weight without compromising on quality.

There are four sizes and styles of the Rab available for purchase, all of which have slightly different measurements to help you find the perfect fit. You can choose from the following designs: long, mummy-shaped, standard rectangular, and traveler.

As a reference point, the standard Rab liner measures 73 inches long and 36 inches wide. In the stuff sack, the Rab will only weigh 5.5 ounces. However, you’ll also notice that the standard Rab is one of the shortest on our list, so bear this in mind when comparing this to other potential purchases.

Although the product detailed above is the standard silk product, Rab also makes this product in either poly-cotton or cotton. Both of these products are significantly heavier than the silk liner. If you can stomach the added weight, however, they will save you a small handful of $.

  • PROs

    • PROs

      • Wide assortment of fabrics and sizes available
      • Fine silk is durable and versatile
      • Weighs 5.5 ounces with stuff sack
  • CONs

    • A bit on the short side 
    • Fairly pricey

Bottom-Line: A great choice for smaller campers looking for a lightweight, versatile, backpacking-friendly silk product that’s as well made as any other model out there.

Best Budget

Dimples Excel

DIMPLES EXCEL Sleeping Bag Liner 100% Cotton Travel Sheet Lightweight Portable for Single (Gray-Cotton)

If you’re looking for an affordable sleeping bag liner that performs nearly as well as its pricier competitors, look no further than the Dimples Excel.

The Dimples Excel is made out of recycled polyester satin. Although it’s not as fine as silk, it can be used in both warm and cold weather, is very breathable, and is quite stretchy. Despite using polyester, which is always a heavier option, the Dimples excel won’t break your back, adding only 8 ounces to your pack.

While it’s not as light or compact as silk sleeping bag liners, the Dimples Excel will get the job done for people who prioritize value rather than packability.

Dimples Excel

DIMPLES EXCEL Sleeping Bag Liner 100% Cotton Travel Sheet Lightweight Portable for Single (Gray-Cotton)

The Dimples Excel is a slightly heavier model that makes up for this shortcoming by providing oodles of warmth and comfort at a very reasonable price point. 

The Excel measures a respectable 86 inches long by 41 inches wide, which makes it a great option for taller campers or people who roll around a lot at night. When it’s compressed into its stuff sack, the Dimples Excel measures 6.3 inches by 2.7 inches and weighs 8.35 ounces.

The product is very thin and made out of recycled polyester satin. More experienced campers might be able to tell the difference between this synthetic fabric and silk, but the texture is quite similar and, like silk, it performs well in both hot and cool conditions.

To get in, you’ll have to open up a few Velcro straps along the side of the product. As you open them up, you can enter the 23-inch opening and simply close the Velcro straps when you’re inside. The advantage of this design is that it’s easier to get in and out. 

The downside is that you might lose a bit of insulation you would have otherwise had with a model that’s sewn together on the bottom and sides.

  • PROs

    • Very roomy size is great for restless sleepers
    • Made out of eco-friendly recycled materials.
    • Side entrance makes it easy to get in and out
  • CONs

    • Polyester material not as durable as silk
    • Velcro straps on the side could weaken insulation and irritate some sleepers 

Bottom-Line: People who are willing to sacrifice the quality of a fine silk product for the affordability of this polyester model won’t be disappointed with the Dimples Excel. One of the best sleeping bag liners out there for buyers on a budget.

Last update on 2021-07-30 / Affiliate links / Images from Amazon Product Advertising API

Brian has been an avid hiker and backpacker since he was a small kid, often being taken out into the wilderness on trips with his father. His dad knew everything about nature and the wilderness (or at least that's how it seemed to a ten year old Brian).

After high school, he went to university to read for both a BS and MS in Geology (primarily so he could spend his time outside rather than in a classroom). He's now hiked, camped, skied, backpacked or mapped on five continents (still need to bag Antartica) & 30 of the US states.