Published Aug 31, 2022 1:00 PM
Sleeping bag liners are an effective way to add a little extra warmth to any camping trip. If you need a few extra degrees of warmth but don’t want to buy a new sleeping bag, adding a liner is a more affordable and packable option.
Like any piece of outdoor gear, sleeping bag liners are made from a variety of materials, from wool to nylon. The materials, general design, and temperature rating will tell you a lot about whether it is the right option for your needs. The best sleeping bag liners are the ones that you can use often and are durable enough to last for years.
Why It Made the Cut: The Big Agnes Wool Sleeping Bag Liner is a versatile wool liner that can be utilized in various temperatures and conditions.
- Weight: 16 oz
- Materials: 87% New Zealand Merino wool, 13% nylon
- Increases Warmth Up To: 5-10°F
- Made from mostly natural materials
- Snaps open and closed on the side
- Mummy style liner
- Hooks on hood and foot to attach to sleeping bag
- Same design is also available in cotton and fleece, but those fabrics do not perform as well and are much heavier
The Big Agnes Wool Sleeping Bag Liner is our top pick for the best sleeping bag liner of 2022. While the same design is available in both cotton and fleece, the wool material is what sells this option. Wool has natural thermal properties, making it a more versatile and comfortable fabric to use in cold and warm weather.
While it isn’t the warmest option on the list, it still adds about 5 to 10°F to your sleeping bag. The mummy-style design is quite snug, but if you use a mummy sleeping bag, it will fit quite well. The hooks on the hood and the foot keep you from getting twisted up in the liner due to the fact that they attach to sleeping bag liner loops (if your sleeping bag has those).
I honestly couldn’t find too many cons to this sleeping bag liner. The wool version is more expensive than the cotton or fleece materials, but the performance and durability make it worth it. It is comfortable and versatile, and with the proper care, will last for years of use.
Best for Warmth
Why It Made the Cut: The Sea To Summit Reactor Extreme can increase the warmth of your bag up to 25°F while still being extremely packable.
- Weight: 14 oz
- Materials: 110g/m² Thermolite fabric
- Increases Warmth Up To: 25°F
- Machine washable
- Good value for the price
- Mummy style with a hood
- Incredibly soft fabric
- Great for cold weather
- Too warm and heavy for some climates and weather
The Sea to Summit Reactor Extreme Sleeping Bag Liner is an excellent way to extend the stretch of your sleeping bag temperature rating. Sea to Summit has various sleeping bag liner options, so if you do not need one this warm, you can likely find something else from the brand that fits your specific temperature needs.
Despite increasing your bag’s temperature by around 25°F, it is still extraordinarily packable and lightweight. The feel of the material will surprise you as it is somewhat thin, but so warm at the same time. Even though use may feel limited to cold climates, with a higher temperature rating, it can also act as a stand-alone sleeping bag on warmer summer nights.
It is perfect for most cold-weather sleeping bags with a mummy-style design. The hood has drawstrings, helping you trap the warmth and increasing the performance of the insulation. Even better, it’s easy to care for and clean—it’s machine-washable and requires no special detergents.
Best for Backpacking
Why It Made the Cut: The Nemo Tracer Sleeping Bag Liner is packable, lightweight, and comfortable, all while utilizing conscious design and materials.
- Weight: 8.3 oz
- Materials: 100% recycled Thermolite EcoMade fabric (polyester)
- Increases Warmth Up To: 5 to 10°F, possibly
- Available in four shapes and two lengths
- Backed by a lifetime warranty
- Antimicrobial finish to reduce odor
- Lightweight and packable
- Made from recycled materials
- Made from synthetic fibers
- Increased warmth rating is not listed
The Nemo Tracer Sleeping Bag Liner is any backpacker’s ideal version of a liner. It is lightweight and super easy to pack and rolls up small. The synthetic material construction makes it a durable option, and with the antimicrobial finish, it doesn’t hold onto odors hardly at all (even on long treks). Although it is made from synthetics, they are, at the very least, 100% recycled fibers.
The Pologeine Odor Control Technology inhibits odor-causing bacteria from attaching to the fibers and extends the time between washing. It’s also a more environmentally sound option as it reduces the number of microplastics it sheds while being washed.
Made of a breathable and thin material, it still seems to add around 5 to 10°F of warmth. Unfortunately, that temperature increase isn’t listed on the brand’s packaging or website, so this is only my guess after using it. I also love that it comes in both a regular and long size and four shape options.
Why It Made The Cut: The Cocoon Mummy Liner is an ultralight and effective sleeping bag liner made from 100% silk materials.
- Weight: 4.4 oz
- Materials: Silk
- Increases Warmth Up To: 9.5°F
- Easy to care for materials
- Breathable yet insulating
- Adaptable to changing temperatures
- Can feel too snug to some users
The Cocoon Mummy Liner is an ultralight sleeping bag liner that delivers excellent comfort and warmth when needed. The extremely lightweight fabric is easy to pack down, and despite the thin material, is very durable.
Silk is a unique breathable fabric and light with adequate insulating properties. Compared to other liner materials, silk is the most similar to a standard sheet you might use at home, bringing a bit of comfort to the trail.
This ultralight sleeping bag liner still adds around 9.5°F but can fluctuate a degree or two in either direction. While it may not be the warmest liner on our list, it is a very comfy and versatile one. The only issue I could see someone having is if they are tall or have a larger build. The liner is a mummy style and can be pretty snug, so getting in and out of the bag might pose an issue for larger individuals.
Why It Made The Cut: The Appalachian Gear Company All-Paca Sleeping Bag Liner is made from ethically sourced, fair-trade alpaca yarn from Peru and then entirely created in North Carolina.
- Weight: 16 oz
- Materials: 100% Alpaca fiber fabric
- Increases Warmth Up To: 15 to 18°F
- Entirely traceable product production
- Soft and comfortable fabric
- Durable and long lasting
- Versatile for travel, camping, or a throw at home
The Appalachian Gear Company is a front runner in textile sustainability within the outdoor industry. The brand’s impeccable transparency with customers and completely traceable supply chain for all of its products build trust and show its commitment to creating quality sustainable outdoor products.
Appalachian Gear’s unique choice to use Alpaca fibers sets it apart from the wool competitors and doesn’t compromise product quality or performance. The All-Paca Sleeping Bag Liner is comparable to wool liners on the market in terms of warmth, but it blows them out of the water in feel and comfort.
While we chose this liner as the most sustainable option, it was honestly a top contender for the best overall. Some may turn away at a price, but quite honestly, it is worth the hype, and it is worth the price. You can tell that the brand is an expert in textiles and has worked hard to craft a sleeping bag liner that can truly stand up to repeated outdoor use.
Why It Made the Cut: If price is your biggest concern, the Teton Sports Sleeping Bag liner is worth considering with a lightweight design at a reasonable price.
- Weight: 12 oz
- Materials: Cotton or polyester
- Increases Warmth Up To: 10°F
- Available in both cotton and polyester
- Resonable price
- Easy to care for and wash
- Packable and lightweight
- Material isn’t very soft
- Sizes run small and can limit movement
The Teton Sports Sleeping Bag Liner is ideal for campers on a budget. There is an option for cotton or polyester materials, and the cotton tends to be somewhat softer and more pleasant to use. Available in two sizes (XL or Mammoth), the liners are still small for what most people may expect.
Depending on what you expect from a sleeping bag liner, having the sides sewn shut can either be a pro or a con. It can help improve heat retention but it limits the versatility and ease of use when getting in and out of your bag.
Overall, this is a decent liner for the price. The materials seem relatively durable, and either option is easy to wash. The pack size and weight are not the smallest, but it is decent for the temperature rating.
Things to Consider Before Buying Sleeping Bag Liners
Before you start shopping, it can help to know what exactly you’re looking to buy. Aside from price and color, there are far more specific criteria that the product should meet to ensure it is the best sleeping bag liner for your outdoor recreation needs.
The apparent intended use is as a liner for your sleeping bag. Within that, there are several variations of use, and some people use them as small travel bag for stays in hostels or hotels instead of within their sleeping bags.
When looking for a liner specifically for camping and backpacking, the intended use becomes more narrow. Ask yourself a few simple questions to identify your needs:
- How much warmth does the liner need to add?
- Will you use the liner as a stand-alone bag?
- Is it lightweight enough for backpacking, or is it only for basecamps or car camping?
- Are there any materials that you don’t like or any that you’re most comfortable with while sleeping?
Knowing how you plan to use the liner, your personal preferences, and the frequency of use helps you identify the best sleeping bag liner for you. Once you answer the questions above, you can move on to other considerations like durability, portability, and budget.
Because a sleeping bag liner comes into direct contact with your body, the materials need to be comfortable enough to sleep. Some materials will be lighter than others, and personal preferences of material textures can also influence buying decisions.
Common materials used for sleeping bag liners include:
- Cotton: A very affordable fabric, cotton is relatively warm and soft. The major downside to cotton is that it can be heavy and it doesn’t insulate when wet. If you have a waterproof sleeping bag, this shouldn’t be much of an issue. Cotton is an excellent option if you only plan to use the liner for things like car camping or in an RV, but there are much lighter fabrics for backpacking.
- Wool: For sleeping bag liners, you will mostly find wool from sheep. However, Alpaca wool is also an excellent choice that shares many of the same qualities as more traditional wool fabrics like Merino wool. Alpaca and Merino wool have very fine fibers, making them soft to the touch, and they do not hold odors like synthetic materials do. The primary benefit of any wool fabric outdoors is that it still insulates when wet. Depending on the type of wool and the thickness of the fabric, it can be lightweight.
- Silk: A lightweight and ideal insulator, silk is a very common fabric used for sleeping bag liners. The biggest selling point for silk is that it has one of the best warmth-to-weight ratios, making it ideal for ultralight liners. Silk is also a durable material that is easy to maintain. What I like most about silk is that while it is good at insulating in cold weather, it is also still breathable enough to be used during warm weather.
- Synthetics: While I’m partial to natural fibers, many sleeping bags are made from synthetic materials, like fleece, polyester, nylon, or CoolMax and Thermolite. These materials are relatively affordable and perform decently well in the field. Synthetics do not insulate as well as wool when wet but dry much quicker than materials like cotton. If a product is labeled as insulated, that generally means it is made from a synthetic blend.
Materials like cotton and synthetics tend to be a cheaper option than silk or wool, but they are not as good at insulating. Opting for natural materials whenever possible is the most sustainable option since synthetic fabrics are almost exclusively made from petroleum and can shed microplastics.
The weight and portability of a liner often come down to the materials themselves. Liners made from silk are almost always the lightest option, but the temperature rating also has an impact.
In most cases, the thicker the material, the warmer it will be. Some very bulky fleece liners out there add a decent amount of warmth, but when compared to liners made from wool or silk, they’re far less portable for the amount of insulation they provide.
Some liners are also easier to roll up and pack into a backpack or can even be stuffed into the same bag as your sleeping bag. How you pack your bag and what you use the liner for influences the portability needed but looking at the weight and dimensions of the packed liner can help.
Design and Features
The best design for a sleeping bag liner is the one that matches the sleeping bag. If you have a mummy bag, finding a similarly shaped liner is ideal so you have additional warmth throughout the entire bag, including the hood.
Rectangular liners are far more common for general travel purposes than travel sheets. If you have a rectangular sleeping bag, these allow for more movement while sleeping. Travel sheets are also a great option when going from hostel to hostel or sleeping in a budget hotel with questionable cleanliness.
Most liners do not have many features, but some may utilize a zipper, a hood cinch, or pockets. If these qualities are important to you, they are worth noting and looking for as you shop.
Are silk sleeping bag liners good?
Yes, silk liners are excellent sleeping bag liners and provide excellent insulation. Silk is a lightweight material, making it ideal for backpacking or travel. The materials are easy to care for and can add anywhere from 5-15°F depending on that specific bag’s design and construction. The main downside of a silk sleeping bag liner is that the cost will likely be higher than materials like fleece or cotton.
What should sleeping bag liners be made of?
Sleeping bag liners should be made from a comfortable, lightweight material that provides adequate warmth for your needs. Many liners are made from synthetic fabrics like polyester, specifically a type of fleece like Thermolite or Primaloft. Natural fibers—including cotton, silk, wool, or alpaca wool—are also a good option for sleeping bag liners.
What is the point of a sleeping bag liner?
The point of a sleeping bag liner may be different for some users, but generally, it’s used to add extra insulation and warmth to a sleeping bag. Other reasons you may use a sleeping bag liner could be to help keep the bag clean or to provide a higher level of comfort. An uncommon but not unheard of use for sleeping bag liners is to act as a protective lining over a sleeping pad.
Are sleeping bag liners worth it?
Yes, sleeping bag liners are worth it. However, they tend to be highly underrated by most backpackers. A sleeping bag liner can expand the versatility of your sleeping bag, increasing the bag’s temperature up to 25°F, depending on the material. Finding one that fits your needs is essential, and not all liners are as warm or lightweight. A compact and portable liner is ideal, but it is only worth it if it matches the environmental temperatures and your heat retention needs.
What do you put under a sleeping bag?
The best thing to put under a sleeping bag is a sleeping pad. The best sleeping pad is the one that fits your specific needs for portability, weight, and comfort. While sleeping pads can make sleeping outside more comfortable, their primary purpose is to add a layer of insulation between you and the ground. Without a sleeping pad, camping can be pretty cold, even during warm weather.
Finding the best sleeping bag liner for your next trip can provide a better night’s sleep by keeping you warm and comfortable no matter the weather. Adding a liner to your sleeping bag is an excellent way to make your sleep system more versatile. Even if you didn’t find the perfect liner on our list, use the buying considerations to narrow down your top picks as you shop.
How We Made Our Picks
Much like choosing the best sleeping bags, finding the right sleeping bag liner depends a lot on how you plan to use it. Sleeping bag liners add more warmth and comfort to a camping trip but can also be used for other travel needs. The fabric’s weight, packability, materials, and feel can all influence your selection process. While we considered all those things, a few important factors helped us select the best sleeping bag liners for 2022.
- Durability: Are the materials long-lasting and designed for outdoor use? Does the company offer repairs or have a lifetime warranty? What type of care and maintenance does the liner require?
- Versatility: Can the liner be used for camping and travel? Is it lightweight while still providing a decent temperature increase? Can you use it as a stand-alone summer bag, or will it only work for cold weather? Are the materials comfortable enough to use year-round?
- Product Transparency: Does the company provide a clear line of communication to the customer about product production? Are sustainability claims clear and truthful? When customers ask questions about products, are they provided with an answer?
- Customer Satisfaction: What do other people say about the product and the company? Do people report more positive experiences than negative ones?
Other things, such as personal experience, gear testing, verified customer reviews, and company-specific research/communication, also influenced our picks.