Which sleeping bag liner should I choose?

To get the most out of your sleep system set-up, we’ve compiled the ultimate guide to sleeping liners—why to use one, how to pick one and how to care for it.

Why use a sleeping bag liner?

cleanliness

You use a sleeping bag liner for the same reasons you put sheets on your bed—hygiene. You probably don’t sleep directly on your mattress or down quilt because they’re a whole lot harder to get clean than a set of sheets.

Out in the wild—in the grimy world of hiking and action-packed adventures—this problem can be tenfold as you bring a day’s worth (who knows, maybe several weeks’ worth) of sweat, dirt and B.O. into your sleeping bag. A sleeping liner is a much-needed barrier that can significantly raise your hygiene standards on the trail. After all, it’s much easier to clean a liner than it is to wash a down sleeping bag or synthetic sleeping bag.

protect your sleeping bag

Using a sleeping liner will increase the life of your sleeping bag. The build-up of oils from your skin can migrate into the down or synthetic fill of your sleeping bag—preventing it from fully lofting and keeping you warm. And who wants to pay for a high-quality sleeping bag only to halve its performance?

The sand that you bring into a sleeping bag can also work its way through the lightweight face fabric. Once these small grains make their way into the insulation, they can act like sandpaper and damage the down or synthetic fill.

comfort

Even lightweight hikers often make room in their packs for a sleeping liner simply because it improves their chances of getting comfy and cozy on the trail. We focus a lot on comfort when it comes to our sleep systems—because it’s the thing that helps you doze off in unforgiving terrain. And in high-stakes situations—like mountaineering, climbing, white-water rafting or paragliding trips—you need your wits about you. You need your sleep.

Comfort is relative, of course—it could be the smooth feel of a silk liner or the legroom a rectangular fit provides (we even have an extra-wide, if that’s your bag). Either way, consider what’s comfortable for you and make it a priority.

add warmth to your sleeping bag

A sleeping liner can add a few degrees warmth to your down or synthetic sleeping bag. Our THERMOLITE® Reactor Liner can add up to 14°F and even a thin Cotton Liner traps an extra layer of air to help insulate.

OUR WARMEST SLEEPING LINER ISN’T A LINER

Our Spark Ultralight 0 Down Sleeping Bag has a comfort level of 50°F and the regular weighs only 7.9 oz. Pop this in your bag to radically boost your sleeping temperature—or use it on its own in warmer weather.

use in sketchy hostels, huts or couch surfing

A big bonus of a sleeping bag liner is that it can serve as a handy travel sheet. Protect yourself from dodgy looking hostel bunk beds or generously offered (but slightly grubby) couches. In summer, a sleeping bag liner can even be used as a standalone sleeping bag.

choosing the right sleeping liner

end use

If you’re trying to extend the warmth of your sleeping bag, a THERMOLITE® Reactor™ Series liner is going to add the most degrees to your bag. THERMOLITE® is a hollow core fiber that traps air so when it’s knitted into fabric, it holds heat in the actual fiber as well as the looped structure of the knit. For this reason, it gives greater warmth-for-weight compared to most liners out there.

If you’re priority is cleanliness, any of our liners will fit the bill—you’ll just have to factor in which weight, packed-size, shape and fabric is right for you.

weight and packed size

Think about what you realistically can carry on your next trip and choose the best option within that weight and size range.

If pack space and weight is at a premium for your next trip, an ultralight and compact Silk Liner (4.8 oz for the tapered mummy version) could fit the bill. Willing to take on a few more grams for a toasty warm sleep? Then 8.7 oz for a Reactor™ Liner is totally worth it.

fit and construction

Our travel liners come in a Standard or Long Rectangular fit, Double, Mummy, Mummy with Hood and Traveller (with pillow insert). Our technical liners are a tapered mummy shape. The best rule of thumb is to choose a liner shape that best fits the shape of your sleeping bag. Or if you’re more swayed by handy construction features—we have liners that come with hoods, pillow inserts and comfort stretch panels.

how to wash your sleeping bag liner

Easily. All our sleeping liners are machine washable and require only your standard laundry detergent. If you’re using a top-loader washing machine, place the liner in a pillowcase or laundry bag first to stop any cords being caught up in the impeller.

Steer clear of fabric softeners when cleaning your liner as they can affect the wicking properties of the material.

To dry your liner, it’s best to hang it on a washing line to air dry. Using a dryer could expose it to excessive heat, which can damage the fabric.

which liner is best for me?

add warmth to your sleeping bag: reactor series

If your sleeping bag needs a thermal boost for a particular trip, check out our THERMOLITE® Reactor Series. You can even use a Reactor as a stand-alone summer ‘sleeping bag’.

Our THERMOLITE® Reactor Fleece Liner is pure toasty luxury—offering both warmth and an incredibly soft next-to-skin feel.

ULTRALIGHT + COMPACT: SILK LINERS

Silk Liners wick moisture and are quick to dry. The Mummy shape is suited for backpacking and the Traveller is a great addition to hostel living. Our Premium Silk Liners have Comfort Stretch Panels along the length of the seam, which helps the liner move with you as you turn.

LIGHT + COMPACT: SILK + COTTON LINERS

Silk + Cotton Liners are great for the same uses as pure silk liners—but their less-shiny surface makes them slightly more grippy. A solid choice for restless sleepers who might get tangled in a pure silk liner.

FOR HOT, HUMID ENVIRONMENTS: COOLMAX® LINERS

COOLMAX® Liners wick moisture and dry quickly. They’re also really stretchy—so if you’ve ever felt constricted in a liner, this is the answer. Available in both a Mummy shape and a rectangular Traveller version with a pillow insert.

VALUE FOR MONEY: EXPANDER LINERS

If packed volume and weight is less of a concern, the Expander Liner is a luxurious addition to your sleep system. The jersey knit construction stretches to almost twice their normal width they don’t have side seams to contend with (with the exception of the Mummy shape). These premium liners also feature an anti-microbial treatment that won’t wash out of the liner, keeping it odor-free.