Layering socks: how two pairs prevent blisters and keep your feet warm

A thin liner under a hiking sock takes the rubbing off your skin. When to wear two pairs, how to layer for cold weather, and which socks to choose.

Wearing two pairs of socks, a thin liner under a thicker hiking sock, cuts the risk of blisters on long days. The liner moves with your foot and the outer sock moves with your boot, so the rubbing happens between the two socks instead of against your skin.

You don't need two pairs for every walk. They help most on long days, with a heavy pack, in new boots and if you're prone to blisters. In cold weather they add a little warmth, but only if your boots have room for them.

In this guide

• How layering socks prevents blisters
• When to wear two pairs of socks
• Layering socks for cold weather
• Sock materials: wool, merino blends and synthetic
• Thickness, cushioning and height
• Mesh zones, seams and reinforcement
• Getting the fit right
• Our socks and what each is for

How layering socks prevents blisters

Blisters come from friction and moisture. Your foot moves a little inside your boot with every step, and over a long day that rubbing, on skin softened by sweat, wears through.

A liner sock is thin and close fitting, so it stays put on your foot. The hiking sock over it grips the inside of your boot. When your foot moves, the two socks slide against each other and your skin is left alone. The liner also draws sweat away from your skin into the outer sock, which helps keep your feet drier.

It reduces the risk rather than removing it. Boots that fit and socks that don't bunch matter just as much.

When to wear two pairs of socks

Two pairs are worth it for:

• long days and multi-day walks, when small rubs build up
• a heavy pack, which presses your feet harder into your boots
• new or stiff boots that haven't softened yet
• feet that blister easily

One good pair is fine for short walks in boots that fit well. And if your boots are already snug, a second pair will make them tight. That squeezes your feet and can cause the pressure points you were trying to avoid.

If you plan to walk in two pairs, wear both when you try boots on. See how to fit walking boots.

Layering socks for cold weather

For winter walking, the usual combination is a thin liner under a thick wool hiking sock. The liner keeps sweat moving off your skin, and the wool sock does the insulating. Wool stays warm when damp, which matters in boots that will get damp from sweat over a cold day.

Layering only keeps you warm if there's room for it. Warmth comes from trapped air, so a boot squeezed tight over two thick socks presses the air out and cuts blood flow to your toes, and your feet end up colder. If your boots are snug, one thick sock is warmer than a thin and a thick one crammed in.

Carry a dry spare pair on cold days. Changing into dry socks at lunch does more for cold feet than adding another layer.

Sock materials: wool, merino blends and synthetic

Wool is warm, cushions well, stays warm when damp and resists smell, so it's the usual choice for hiking socks. Lambswool, the soft wool from a sheep's first shearing, is what we use in our thicker hiking socks.

Merino blends mix fine merino wool with synthetic fibres. They're lighter and thinner than lambswool, dry a little faster, and still resist smell. Ours use Coolmax fibres to move moisture and Thermolite fibres for warmth.

Synthetic socks, mostly polyamide (nylon) and polyester, dry fastest and wear well, which suits running, cycling and warm weather. They resist smell less well than wool.

All our hiking socks add polyamide at the heel, toe and sole, where socks wear through first. Avoid cotton: it holds sweat against your skin, which softens it and makes blisters more likely.

For wool socks, wash cool and skip fabric conditioner. See how to wash merino wool clothing.

Thickness, cushioning and height

Thick or thin? Thicker socks add warmth and cushioning for long days, rough ground and heavy packs. Thinner socks are cooler and suit lighter shoes and warm weather. Match the sock to the boot: a boot fitted with a thin sock will be tight with a thick one.

Cushioning sits where your foot takes the most pressure, at the heel and the toe. Running and cycling socks keep it to a minimum so you can feel the ground or the pedals.

Height should come above the top of your footwear. Crew and mid-calf socks suit walking boots and stop the cuff rubbing; ankle socks suit running shoes.

Mesh zones, seams and reinforcement

Ventilated mesh zones are panels knitted more openly, usually across the top of the foot, so heat and sweat escape where your foot gets hottest. You'll find them on running and cycling socks.

Seamless toes remove the ridge across the end of a sock, which is a common spot for rubbing on long descents.

Reinforcement with tougher fibre at the heel, toe and sole makes socks last longer where they take the most wear.

Getting the fit right

A sock should be snug with no spare fabric. Too big and it bunches and folds, which causes friction and hot spots. Too small and it pulls your toes down and thins out over your heel. The heel of the sock should sit in your heel, not above it.

Fit your boots with the socks you'll walk in. See how to choose walking boots for the rest.

Our socks and what each is for

For a two-sock system: Mesa and Esker liners. Thin and close fitting, made to go under Liskam, Ushbar or Talus. Mesa is Coolmax, highly wicking, in a pack of two. Esker is a merino blend with Coolmax and Thermolite, for warm, dry feet on longer hikes and multi-day trips.

For lighter days, spring to autumn: Liskam. A lightweight merino blend with cushioning at the heel and toe. Crew length, for boots, approach shoes or gravel shoes. Liskam.

For big days in the hills: Ushbar. Mid-weight lambswool for year-round walking, long crew length for boots and shoes. Ushbar.

For cold days and mountain boots: Talus. Heavyweight lambswool for four-season hillwalking and cool-weather mountaineering, mid-calf height for walking, mountaineering and ski boots. Talus.

For running: Scape, ankle-length polyamide with mesh panels for hot, fast runs, or Repeat, a cushioned merino blend for longer trail runs.

For cycling: Stage, crew-length polyamide with mesh panels for road and gravel, or Divide, a mid-calf merino blend for gravel and bikepacking.

See all socks.

Related guides

• Best hiking socks for comfort and durability: our hiking socks matched to the walks you do
• How to choose walking boots: fitting boots around your socks
• Merino or synthetic base layer: the same fibres, next to your skin

Next up in our series The Complete Guide to Outdoor Clothing: Dexterity is the focus as we explore how gloves and mittens protect your extremities, we think you will find it very handy.

1. The Complete Guide to Outdoor Clothing: Layering Systems That Work
2. Base Layer Guide: Merino Wool vs Synthetic Materials
3. Mid Layers Guide: Fleece and Natural Fibres
4. Insulated Jackets: Down vs Synthetic Complete Guide
5. Waterproof Jackets: Your Complete Guide to Staying Dry
6. Outdoor Trousers, Shorts and Leggings: Your Complete Guide
7. Hiking Socks Guide: Materials, Cushioning, and Fit
8. Keeping Your Hands Warm: The Complete Guide to Outdoor Gloves