Outdoorsy types tend to spend a lot of time and money on the perfect warm boots for winter weather, but there’s another key bit of kit for keeping your feet cosy in the cold – great thermal socks. The right pair of thermal socks can be the difference between an enjoyable alfresco adventure and a cold, miserable experience on a mountain hike or a ski trip. Not sure where to start? Here’s what to look for when shopping for the best thermal socks, whether you’re hitting the slopes or embarking on a frosty hike this winter season.
Wool, particularly Merino wool, is a top choice of material for warm socks as it’s naturally insulating, moisture-wicking, and odour-resistant, keeping your feet warm and dry even in freezing conditions. Merino wool also regulates temperature well, so your feet won’t overheat if you’re getting active. You’ll also find socks that combine wool with synthetic fibres like nylon or spandex for durability and stretch on the market. Bamboo is another wonder material as it’s super comfortable, breathable, naturally antibacterial and doesn’t itch.
Next, consider fit and padding. Skiing socks should be snug, offering a tight fit to avoid bunching inside your boots, which can cause blisters. Ski socks usually feature padded shins, to protect your legs against hard ski boots. Hiking socks should have extra cushioning in the heel and toe for added comfort over long distances and both types of socks should be high enough to cover your ankle and fit well inside your boots, but not be so thick that they cramp your toes.
Lastly, breathability is crucial. Your feet will sweat when you’re active, even in the cold, so socks with good ventilation zones or moisture-wicking fabrics can prevent that damp, cold feeling.
Investing in a few high-quality pairs of socks will make sure your feet stay warm, dry, and comfortable—so you can focus on the next adventure, not your frozen toes.
How we tested
We tried out each of these pairs of socks over a few miles of hiking in the Lake District and looked for good comfort, cushioning where it counts and decent breathability. We also washed each pair to see how they held up to regular use.
The best thermal socks for 2024 are:
Sealskinz northwold solo thermal ski sock
A lovely ski-style sock you can also wear for hiking, working outdoors in wellies or for just keeping toes toasty at home. Sealskinz northwold is thin enough to fit nicely in hiking boots but cushioned enough to wear for snow sports or in rubber boots, and the wool and nylon blend is the perfect balance of warmth, comfort and moisture-wicking – we found these socks were surprisingly breathable on test. Padding in the footbed is brilliant for spending long days outdoors in bulky footwear. The ‘multi’ colourway looks pleasingly retro, too.
Buy now £30.00, Sealskinz.com
Mountain Warehouse polar womens Merino technical knee length ski socks
A great option for under £15, these comfy-as-anything socks from Mountain Warehouse are warm and cosy on the toes thanks to a Merino wool mix and look rather lovely too, with a patterned snowflake design. Although they’re aimed at skiing there isn’t loads of cushioning built into the polar socks, so we’d stick to wearing these knee length socks for winter walking or popping in your snow boots or your wellies, when their warm make-up comes in very handy.
Buy now £14.99, Mountainwarehouse.com
Sealskinz uphillsport Valta alpine
Is this the perfect ski sock? Sealskinz’s unisex Valta is inspired by the mountain of the same name in Finland and is ready for the cold. This sturdy sock is knee-length and has good padding where it counts. The fabric blends Merino wool for warmth and fast drying with polyamide for stretch, resulting in a comfy fit that can handle subzero conditions. The standout feature is the seamless toe, which avoids any blisters when you’re skiing all day. These socks are on the pricy side, but if you ski regularly a few pairs are well worth the investment.
Buy now £36.99, Sockshop.co.uk
BAM technical bamboo ski sock
Bamboo is a bit of a wonder material for socks, as it’s deliciously comfortable against the skin and is naturally antibacterial, and BAM makes the best bamboo socks, base layers and snug knits in the business. These terry-lined ski socks combine bamboo with breathable mesh, offer compression support and are created with an invisible toe seam, so there’s no rubbing or bunching in boots. These socks have some cushioning but are better for casual use rather than hardcore hiking or skiing. These bamboo beauties are a bit of a bargain, too.
Buy now £12.00, Bambooclothing.co.uk
Falke SK1 comfort women skiing knee-high socks
The clue is in the name – these knee-high socks are deliciously comfortable. Stretchy enough to hug your leg and stay put all day long, they sit well inside tight ski boots, with lots of cushioning on the shin to protect you even if you’re out in the elements all day. The Merino wool and silk mix of the SK1 is breathable and odour-resistant. We tested out the female-specific SK1 sock, which is ideal if you have small or narrow feet. The men’s SK1 will suit male skiers or women with bigger feet.
Buy now £29.39, Amazon.co.uk
66 North primaloft ski socks
You’ll usually find primaloft synthetic insulation stuffed into your favourite padded jacket for some welcome warmth, but it’s a great material for thermal socks, too. Icelandic brand 66 North uses it to craft yarn for these sumptuously soft ski socks, which are brilliant all-rounders for casual wear all winter long. If you do end up with holes in your new socks, 66 North also offers lifetime repairs. We like the simple, sporty white look and 66 North branding on this design, but it might not suit everyone, and the white could look dirty easily, so black is probably the more sensible choice.
Buy now £40.00, 66north.com
Darn Tough vanna grizzle womens hiking socks
A sock to last you a lifetime of adventure? Darn Tough’s designs all come with a lifetime guarantee, and if you end up working them so hard they get holes in, the brand will replace them for you for free. There also are myriad styles and colourways to choose from, most of which are far cheerier than your average plain hiking sock. We love these vanna bear and moose socks, inspired by retro sweaters and with Merino wool added in for warmth. This midweight sock works well for hiking in autumn and milder winter weather.
Buy now £30.00, Darntough.uk
Smartwool ski zero cushion rainbow trails
Swoop down the pistes armed with the perfect combo of tough performance and fun looks in these jazzy rainbow socks from Smartwool. Thin and flexible, so they sit well in tight ski or snowboard boots, but with 55 per cent Merino wool for plenty of warmth, these socks are great for serious snow sports fans who don’t like boring kit. This model is a ‘zero cushion’ sock with no added panelling but ‘targeted cushion’ and ‘full cushion’ versions are also available from Smartwool, so you can pick the level of cushioning that feels the most comfortable for you.
Buy now £28.00, Smartwool.co.uk
The verdict: Thermal socks
We reckon Sealskinz make the best all-rounder thermal socks, with the Sealskinz northwold socks, but the uphillsport Valta alpine socks are up there for the best ski socks, too. Darn Tough’s vanna grizzle are perfect for hikers (and look great) while BAM and Falke focus on comfort.
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