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Rated 5 out of 5 by from Great Hot or Cold... I have worn these socks on a daily basis in Danner work boots summer and winter, and inside a pair of White's Pac-Boots in extreme cold conditions for the last 5 years while working in the forest. I wear a fresh pair each day, and with weekly washing they have held up great.I keep about 6 pair on hand, and I have only had to replace them about every 18 months on average.Drying them in the dryer takes a toll on the elastic in the upper part of the socks over time.They are a lofty sock and wick moisture away from your skin in hot or cold to keep your feet comfortable, and give additional cushioning to your feet.
Date published: 2009-08-05
Rated 4 out of 5 by from So warm I forgot I had feet Great product! In terms of warmth, they hold heat all day. I spent a day on the slopes in Colorado with them and never had any issue. Usually, my feet get cold a few hours into any outdoor activity in the the winter, but with these I never noticed any creeping coldness. However, with the good comes the bad. The reason I gave them 4 stars was because they fit a bit large. While they are super warm the elastic band at the top that fits around the calf is the only part of the sock that seems to stay formed around your leg. Everything else fits loosely. Although there is this issue, the primary reason for purchasing this sock is warmth and under that criteria it passes. I would recommend this sock.
Date published: 2014-01-31
Rated 5 out of 5 by from Very good socks for hiking I bought this socks for hard tracking with backpack over 20 kg and radial excursions to peaks. It have been tested in the winter outdoor event where we pass from 1200 up to 3095 meters, temperature was from -3 to -12 celcius degree. And it was snow up to 60 cm. I have a little problems with cold legs only at night when we stay for two hours while waitings for ropes mounted. All other time my feets was dry and warm. Finally it is only socks I have no any blisters with my Salewa Bison GTX trecking boots! I planned to use them one day only but feel very comforatable for more than 3 days. Now I planning to buy two additional pairs for everyday outdoor usage.
Date published: 2012-01-15
Rated 5 out of 5 by from Must have Summit Sock! This sock coupled with a good liner (I tend to size my liners one size smaller so they don't bunch) is the perfect combination for a summit climb. Wore these on Mt Adams this past summer and my feet stayed perfectly warm in my old set of Raichle boots (didn't have enough to break in my new La Sportiva's). This is warm sock, and does a good job wicking away the moisture. Also they are bulky. So if you hike the year round in a medium to heavy hiking/backpacking sock, this sock is one-up from that. Don't try to cram you foot into a snug boot (I buy mine 1/2 size larger for this reason), it will defeat the purpose and keep your feet cold. They are spendy, but this will be the one and only pair of winter/mountaineering socks you'll ever need to own. Hike on!
Date published: 2013-11-30
Rated 4 out of 5 by from Great socks, run larger to size Bought these socks as I love merino and love Smartwool socks. I have a few light and medium weight smartwool socks and I rate them highly.  These socks are very thick, very warm and are very cushioned meaning that walking is comfortable. I use them with a part of insulated snow boots.  My only critique would be the size. I bought these to wear as a single layer sock in my boots, I usually wear a size L Smartwool sock as my shoe size is right in the middle of the range (im a 43.5 - 44 Euro size). These socks run much larger and when I wear them alone, the heal tends to ride up the back of my foot. They do work well when I use a medium weight liner sock underneath them.  If you don't want to run a liner sock, I suggest you size down. If you do use a liner sock then order in your normal size.  The overall quality is very high. 
Date published: 2014-04-26
Rated 5 out of 5 by from B.I.G. I can't fit comfortably in any of my regular footwear with this, so I mostly use it solo, as slippers. Oh, it'll fit, but the whole point of these socks is -to create air space- for insulation. If you -pack it in- then it won't function as -warm- as intended. I wear 11.5-12 in Mens shoes. I am an in between L-XL. I got these in XL and I can't fit comfortably in any of my regular shoes, from athletic (12) to boots (11.5). I do have an odd pair of size 12 boots I got because they were a good deal (and haven't parted with them), and these socks fit great in them. If you're going to use this for -warmth- in your boots, go 1/2 size up, with the boots, for proper fit and function.
Date published: 2017-01-14
Rated 5 out of 5 by from Amazing I bought my guy 3 pairs of these over a year ago for use in his work boots. He not only wore them all winter, but all summer too. Besides the fact that he loves the way they feel, even though these 3 pairs have been in heavy rotation for a year, they show very little wear.
Date published: 2013-09-23
Rated 5 out of 5 by from Worth Every Penny I use these socks on a daily basis in the fall, winter, and spring. After wearing the first pair over and over, I decided that I should get more before I wear out the first pair. I own 3 pairs to cycle through the week. They are cushy, very comfortable, and keep your feet warm and dry. After a long hike with a heavy pack, it's my legs that are hurting, not my feet. I prefer these socks over every other pair of socks I have tried, besides the SmartWool Hiking socks for the summer. A+
Date published: 2014-01-27
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Questions & Answers

Does this come in size Small? What are women with small shoe sizes supposed to wear? =/

Asked by: OptOutside
Unfortunately, we don't have this sock available in size small. We do offer the similar REI Co-op Merino Wool Expedition Socks in size small.
Answered by: REIservice
Date published: 2017-01-20

I wear between 6.5 and 7 women's you think i'm better off with Small or Medium? Thanks! -E

Asked by: Eileen
​We suggest size small for you.
Answered by: REIservice
Date published: 2018-01-30

Any idea how many miles these socks maintain their cushion properties? Mine are still looking good and show no wear or tear after 1000+ miles - but I wonder if one should be replacing them earlier? I sense the "padding" is less...

Asked by: Andy Schmidt
Smartwool does not offer a guide as to how many miles you can wear the socks before you should replace them. If they are comfortable to you right now, I suggest you continue wearing them as long as they are comfortable.
Answered by: REIservice
Date published: 2017-01-28

Hi!  Just got these & wondering on care? Can I wash in washing machine & what temps? Dryer too? It has 2 pictures that I don't know what they mean. 

Asked by: Lars5
These socks can be machine washed in warm water on the gentle cycle. Do not use any bleach, do not iron and do not dry clean. They can be tumble dried with low heat or hung to dry.
Answered by: REIservice
Date published: 2017-09-16
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