Among the myriad merino wool companies out there, Minus 33 is perhaps the most aptly named. The New Hampshire-based company has specialized in merino wool since 1916, establishing a reputation for creating some of the heaviest heavyweight merino wool items around. Many of those are geared toward a hardcore snow-sports crowd, but the heavyweight items got my more-casual attention as well since I suffer from Raynaud’s syndrome. Heavyweight generally means warm. So after hearing that the Minus 33 Expedition wool socks were their “warmest sock yet,” I naturally had to buy a pair to feel it for myself.
The first thing you notice after slipping on the Minus 33 Expedition wool socks is just how thick they are. I’ve tried more socks over the years than I care to admit, and I’m continuing to test more for the sake of warm feet and readers’ education. As of this writing, Minus 33’s Expedition socks are by far the thickest — and the warmest. You can sense my enthusiasm on this initial Twitter post, and I’m pleased to report that each outing since then has yielded a similar toasty result.
Two aspects make the Minus 33 Expedition wool socks stand above the rest, though one of those might turn some people off. The first feature is the socks’ thickness. I’ve been incredibly pleased with the Woolx midweight merino socks, which are surprisingly thick in spite of being billed as “midweight.” However, the Minus 33 socks have 7% more merino wool in them (82% compared to 75%), which makes a surprising difference in both bulk and insulation.
The potential downfall of this thickness is that you need to be more mindful in terms of interior shoe or boot “wiggle room.” It also means you won’t be wearing these big boys in summer unless you’re at serious altitude. However, the material does have enough “squish” to it that the socks fit comfortably into a pair of KEEN Marshall WP hiking shoes, so it’s not like they require a boot that you’d otherwise be swimming in. And let’s face it, when you want to keep your feet warm, thickness is an expected — and welcome — feature. It also makes them slipper-like cozy.
A second differentiator with the Minus 33 Expedition wool socks are their length. Unless you buy snowboarding or skiing socks, you don’t often see full-calf coverage. That’s exactly what the Expeditions offer. This is a huge boon to keeping warm, because it extends that sense of insulation well above your upper ankle. It also serves a practical purpose of bridging the gap if you’re wearing 3/4-length leggings that don’t extend all the way down to your ankle.
In most cases this length is a great thing. I really noticed it helping out my entire leg-warmth situation, for example. However, it does take a bit of getting used to if you’re not familiar with longer-length socks, so you need to know what you’re in for. From the tip of the toe to the top of the calf area, the Minus 33 Expedition wool socks measure 20.5 inches long — about 11 inches of that from the ankle up. That’s long.
Minus 33 thought of a few other nice features with the Expeditions. Among them are nylon-reinforced heels and toes for added durability, flat-toe seams to avoid blistering on long walks, and making them fully machine washable and dryable. These nice touches make my biggest complaint all the more frustrating: they’re really tight on the calf.
You can see a bit of this tightness in the image at the top of this review. The socks stretch quite a bit without getting drafty, as you can tell by the width of the striations and lack of skintones beneath them. However, the socks left indentations in my calves after wearing them for 30 minutes, and I don’t exactly have massive bodybuilder legs. On several hikes the top of the socks actually slipped down my leg, presumably to find a point of less stretch resistance. This resulted in some bunching right above the ankle, which although it did keep that area warm, ironically reduced the heat gains that would’ve otherwise resulted from their length. Neither of these tightness-related incidents is enough to stop me from wearing the socks, but both could’ve been solved by adding a bit more girth to the calf area.
With all that said, the Minus 33 Expedition wool socks get my hearty recommendation. I can tolerate a little tightness and occasional slippage for the promise of warm feet, and that’s precisely what these socks offer. Heck, I’ve dealt with tight and slipping socks in the past that didn’t even keep my feet warm, so I take it all in stride. These probably aren’t socks for a shoulder season, and they’ll keep your feet warm enough that you should make sure your footwear is quite breathable (the KEEN Marshalls aren’t the best at that). Minus 33 said the Expeditions were their warmest sock yet. That’s probably true. They’re certainly the warmest sock I’ve ever worn.
I purchased the Minus 33 Expedition wool socks for use and review. All opinions and words are my own and honest, and the article contains no affiliate links.
Minus 33 Expedition Wool Socks
- Outstanding cushion
- Unmatched warmth and insulation
- Long length keeps calves warm too
- Machine washable and dryable
- Snug isn't the same as tight, and these are a bit tight at the top
- The socks collapsed / slipped down my calf over longer hikes