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Smartwool PhD Ski Medium Review

If you're seeking a ski sock for the season, this is the most reliable with the best overall performance.
Editors' Choice Award
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Price:  $27 List | $26.95 at REI
Compare prices at 2 resellers
Pros:  Warm, comfortable, durable, reliable
Cons:  No lifetime guarantee
Manufacturer:   SmartWool
By Amber King ⋅ Senior Review Editor  ⋅  Mar 7, 2019
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RANKED
#1 of 7
  • Comfort & Construction - 20% 9
  • Warmth - 20% 9
  • Drying Speed & Wicking Ability - 20% 8
  • Fit - 20% 8
  • Durability - 20% 9

Our Verdict

Setting the standard for quality and performance across the board, the Smartwool Ph.D. Medium is our go-to for wear in all things winter. This longtime favorite just keeps winning our Editors' Choice Award for its unbeatable performance and thoughtful engineering. The plush merino wool blend doesn't just offer exceptional comfort, but it's 'close to the skin' fit promotes enhanced thermoregulation to keep you warm, whatever the weather, on the slopes. We've been testing this sock for over five years, wearing it while ski mountaineering, resort skiing, backcountry splitboarding, camping, and even on frigid mountain bike rips. In all cases, it's kept us warm, dry, and comfortable. Some other sock options one-up the Smartwool Ph.D. in some metrics, but none demonstrate the unbeatable performance and dependability of this all-around ski and snowboard sock.

Our experts also tested the women's version of this sock. The major differences are narrower dimensions in the foot width and calf circumference.

If you were to choose one sock for the whole season (and those to come), the Smartwool PhD is our recommendation. The Icebreaker Ski+ Light did prove to dry a little faster than the Smartwool but isn't nearly as durable. The Darn Tough Over-The-Calf Padded Light, our Top Pick for Wicking Ability outperformed both of these competitors in its wicking ability and durability, but it just isn't as warm nor as comfortable as the PhD.


Compare to Similar Products

 
Awards Editors' Choice Award Editors' Choice Award Top Pick Award  Best Buy Award 
Price $26.95 at REI
Compare at 2 sellers
$26.95 at Amazon$24.95 at Backcountry
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$21.26 at Amazon
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$10.00 at Amazon
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Pros Warm, comfortable, durable, reliableDurable, comfortable, warmSuper durable, great fit, super wicking ability, lifetime guaranteeQuick to dry, comfortable, lighter padded constructionPriced right, warm when dry, comfortable, lightweight
Cons No lifetime guaranteeLacks lifetime guarantee, expensiveNot very warm, no additional paddingLacks durabilityCold when wet, durability is so-so
Bottom Line If you're seeking a ski sock for the season, this is the most reliable with the best overall performance.An industry standard that should be part of everybody's winter wardrobe.A lightweight sock that will keep your feet dry even on the warmest days of winter.A quick to dry well-rounded ski sock that can perform in all conditions, wet and dry.The best valued sock in this review for skiing or snowboarding.
Rating Categories Smartwool PhD Ski Medium PhD Ski Medium Over-the-Calf Padded Light Icebreaker Ski+ Light Fox River Telluride Medium
Comfort & Construction (20%)
10
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9
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9
10
0
7
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8
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8
Warmth (20%)
10
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9
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9
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6
10
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8
10
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7
Drying Speed & Wicking Ability (20%)
10
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8
10
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8
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10
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9
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6
Fit (20%)
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Durability (20%)
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Specs Smartwool PhD Ski... PhD Ski Medium Over-the-Calf... Icebreaker Ski+... Fox River...
Material 65% Merino Wool, 33% Nylon, 2% Elastane, Imported Yarn 62% merino wool, 36% nylon, 2% elastane 60% Merino Wool, 36% Nylon, 4% Lycra Spandex 57% Merino Wool, 40% Nylon, 3% Lycra 53% acrylic, 27% nylon, 18% Merino/wool blend, 2% spandex
Level of Cushioning Medium (feels lightweight) Medium (feels lightweight) Ultralightweight Lightweight Lightweight
Weight of both socks 3.15 oz 2.95 oz 2.85 oz 3.15 oz 2.80 oz
Left/Right specific? No No No Yes No
Overall height 13 inches 13 inches 14 inches 14.25 inches 13 inches
Padded area Shin, underfoot, ankle Shin, underfoot, ankle Shin Shin, calf, foot, ankle Shin, heel, ankle
Warranty or Guarantee Head to Heels Guarentee upon arrival w/ 2 year Guarentee Head to Heels Guarentee upon arrival w/ 2 year Guarentee Unconditional Lifetime Guarentee Lifetime Guarentee One year warranty

Our Analysis and Test Results

Featuring "indestructawool" technology, this Editors' Choice winner isn't just durable but warm and comfortable to wear all day long. Whether you're a professional athlete or taking your first turns on the slopes, this is our top recommendation and go-to if you're looking for a comfortable sock that will last you the rest of the season and those to come.

Performance Comparison


Shredding lines in the Northwest feels better with a bomber sock like the Smartwool PhD Medium that offers warmth  breathability  and comfort of all-day wear.
Shredding lines in the Northwest feels better with a bomber sock like the Smartwool PhD Medium that offers warmth, breathability, and comfort of all-day wear.

Comfort & Construction


We are absolutely delighted by the amount of cushioning and comfort offered in the construction of this midweight (that feels like a lightweight) ski and snowboard sock. Constructed of 65% Merino Wool, 33% Nylon, and 2% Elastane, not only does it stretch and stay in place, but provides great overall thermoregulation. Its construction specifically features the most padding of any sock tested. Though, Smartwool has done an amazing job at retaining a thin construction with plush materials.


Loaded with a soft underfoot padding, both recreational and elite skiers and snowboarders boasted of the comfort they felt all day on the mountain. The padding at the toes, underfoot, and heel provide an extra layer of insulation while the padding at the shin provides a little protection for "shin bang" for skiers. The Achilles is also protected with an additional strip of fabric - all specific to potential pressure points for boots that don't fit the way they should.

A look at the internal construction that offers strategic padding.
A look at the internal construction that offers strategic padding.
The shin padding is comfy and stretchy providing a precise fit.
The shin padding is comfy and stretchy providing a precise fit.

While skiing, the compression panels at around the arch, top of the foot, and ankle provide amazing thermoregulation and keep the sock in place. Smartwool created a unique latticework of padding that weaves above the thin compression paneling on the top of the foot. During skiing, it is nice because while there is ventilation with a little padding to make the experience a little more comfortable.


Overall, this is the the most comfortable contender tested. The Icebreaker Ski+ Light is another super comfortable option for your feet. It's also a great alternative if you prefer a padded underfoot with thinner construction.

Warmth


This is one toasty sock! If you like slipping your foot into something that insulates and provides warmth all day, then you've gotta check out the Smartwool PhD Medium. The compression paneling does a great job venting moisture so the sock doesn't hold moisture after you've begun to sweat. This is surprising given it's thicker and more insulative construction. The higher proportion of wool used in its construct aids in making it one of the warmest options out there.


Our testers have been skiing with this sock for over five years. We've subjected it to uphill escapades that have involved climbing over 2,000 vertical feet and skiing down different slopes. Through these testing periods, our feet haven't ever gotten cold. The merino wool, while thick, provides amazing insulation. When sweating, the material can quickly wick the moisture from the skin and transport it to the other side of the sock. This allows for better overall warmth management on the slopes.

We enjoy great overall warmth on both bluebird days and cold cloudy ones with cold temps.
We enjoy great overall warmth on both bluebird days and cold cloudy ones with cold temps.

In addition to backcountry split-boarding and skiing, we've also tested this sock extensively on the resort slopes. Our testers have worn it day after day while tackling temps that have dipped into the double negatives. Cold days sitting on the chairlift sometimes necessitate some boot warmers, but with the Smartwool we are confident to say those days were fewer and farther. Overall, this sock is warmer than any other contender and does a great job with moisture management. The biggest reason it's our Editors' Choice Award winner.

Drying Speed & Wicking Ability


Breathability comes in the form of its ability to wick away moisture and transport it away from the skin of the foot. In the case of this product, it does a pretty good job at this. This, once again, is attributed to its strategically placed compression paneling that offers additional sites of moisture transport. In the areas of higher padding where moisture would otherwise have a harder time moving (due to thickness), the integrated nylon aids in wicking it away from the surface of the foot, providing more warmth overall. In terms of drying, it does dry quickly for a ski sock…allowing you to use it for a couple of days on end…but it's not the fastest to dry out there.


The integrated merino wool does an amazing job at moving water vapor from the skin to the surface before it condenses into a cold sweat. The only time that we noticed our socks getting a little bit damp was when the sun came out and warmed the air.

The material is tightly knit that fits closely to the skin that wicks away moisture efficiently.
The material is tightly knit that fits closely to the skin that wicks away moisture efficiently.

The only socks that did dry more quickly were the Icebreaker Ski+ Light and Darn Tough Over-The-Calf Padded Light. In cooler temps that you'd expect in the winter, our feet stayed dry, at the resort and in the backcountry.

We tested this sock while playing in the Alaskan range. Here we got to truly test temperature and breathability.
We tested this sock while playing in the Alaskan range. Here we got to truly test temperature and breathability.

Fit


This sock truly 'fits like a glove'. Integrating Elastane into the construction, it bounces back and fits nicely inside a pair of tighter ski and snowboard boots. While the padding does provide additional comfort, it's not so lofty that it gets in the way fit. The length of the sock rises midway up the calf. While this sock is quite stretchy with a super specific fit that doesn't move while it's on, many of our testers commented that it almost felt like a compression sock.


Designed to fit tightly against the skin to amplify wicking ability, this sock feels tight. Many of our testers liked this fit attribute, but some complained of it almost being too tight. That said if you've got calves that are pretty big, the body of the sock may not fit. If that might be you, be sure to try them on at a store, or order them with a solid return policy. If you think this might be you, check out the Icebreaker Ski+ Light or Darn Tough Over-The-Calf Padded Light instead. Both offer a little more volume in the calf. Alternatively, if your calves are pretty normal or even more petite, you'll probably love the fit of this sock.

A look at the overall fit of the Smartwool PhD Medium.
A look at the overall fit of the Smartwool PhD Medium.

Not only does it fit tightly and precisely, but the Merino wool materials are soft and luxurious. The hem band at the top stays up and doesn't slide down so you can slide down slopes all day long. Overall, we love the fit of this sock. It doesn't compromise on ski or snowboard fit.

If you like the sounds of this sock, but prefer a lightweight option, check out the Smartwool PhD Light Ski Sock instead.

Durability


Testing this sock for over five years, we are happy to report that it is simply bomber. While the merino wool does pill and shrinks slightly after the first wash, we haven't had any real issues, even after years of use.


Our main testers have used this in a rotation with another sock, and it's still going strong after this time period. As a result, we deem it one of the most durable options tested. While it doesn't come with a lifetime no questions asked guarantee like the Darn Tough, it does come with a 2-year satisfaction guarantee.

While we observe minor pilling  we've tested this sock for many years. In these years its proven to retain its warmth and bounce back  providing great overall durability.
While we observe minor pilling, we've tested this sock for many years. In these years its proven to retain its warmth and bounce back, providing great overall durability.

Best Applications


With awesome performance all over the board, this sock is best suited for skiers and snowboarders of all abilities. It excels in cold environments where you require all-day comfort, wicking ability, and warmth. The additional padding doesn't compromise fit for a skier with a tight boot, and the materials have proven to last for many years. If you prefer a thinner sock option, Smartwool PhD offers this sock in a light and ultralightweight, which might cater to those who prefer super thin socks.

If you're looking for a sock that you can wear all day at the resort or while exploring the glaciers of Alaska  this is it! If you're to choose one option  and you've got the cash  this is it.
If you're looking for a sock that you can wear all day at the resort or while exploring the glaciers of Alaska, this is it! If you're to choose one option, and you've got the cash, this is it.

Value


Retailing for about $27, the price might be high but durability and performance are also high. So yes, this sock is definitely worth its price. As a high-value option, you simply can't go wrong with this all-around performer that does well in pretty much any type of cold weather environment.

Conclusion


Winning our Editors' Choice Award, this ski and snowboard sock is perfect for everybody looking to keep warm in cold temperatures. Its precise and well-engineered architecture allows for superior wicking ability while balancing wear-all-day comfort. Wear it from the slopes to the bar, and back to bed.


Amber King