I spent a lot of time last year thinking about mountaineering boots and socks. What I’ve decided (as far as socks) is that a mostly wool (say greater than 50%) acrylic blend is warmest for me. This isn’t anything ground breaking. What is funny though is that you can pay a lot or a little and it doesn’t seem to necessarily change how warm a sock will be.
I bought some relatively thin 45% Merino wool blends for about $4 a pair from an Eddie Bauer Outlet. These socks tend to be twice the thickness of a thin synthetic liner sock but offer significantly more warmth for little additional weight. Similarly the standard Smartwool men’s hiking midweight crew is a great value and offers less bulk than a full on winter mountaineering sock, even when layered with a liner.
A surprising find was a pair of North Face ‘Multisport’ quarter height wool blend training socks. They look quite similar to the EB First Ascent ‘Mountain Training Sock’ and offerings by Darn Tough VT or Icebreaker, and have been my go to sock for running on cold wet snowy days. Perhaps not quite as surprising, but the socks that were the overall winners for Alaska & winter in general, were the Patagonia Ultra Heavyweight Mountaineering Socks. They are indeed what they claim to be. Ben even wore my backup pair after summiting Denali on day four.
As far as the Thorlo & Smartwool ‘mountaineering socks’ I found the over calf length a bit too long compared to Patagonia. I think they’re both quite warm, with a slight nod to the Thorlo in terms of warmth, but ultimately they were both too bulky and the fit wasn’t as good as Patagonia’s heavyweight wool mountaineer. YMMV.
As far as liners, I found little variation, but did notice that at higher altitudes I had to make sure there wasn’t any constriction from the top elastic band. Initially I thought tall knee height ski liners were the best option, keeping my legs warmer, but then I realized they tended to squeeze my calves causing painful constrictive brusing, so I stuck with the standard height Patagonia lightweight synthetic hiking liner socks and had no problems. If you do have tall ski boots you’ll obviously need taller socks, just be mindful of swelling especially while sleeping in the cold at night.
This mini review is just my personal take on it. I bought all these socks out of pocket with my own funds and now I own two drawerfuls of socks.