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Smartwool PhD Pro Light Crew Review

A hiking sock that performs well through all seasons for any distance
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smartwool phd pro light crew hiking socks review
Credit: REI Co-op
Price:  $28 List
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Manufacturer:   Smartwool
By Amber King ⋅ Senior Review Editor  ⋅  Aug 26, 2019
  • Comfort - 25% 9.0
  • Wicking and Breathability - 25% 8.0
  • Warmth - 20% 8.0
  • Durability - 20% 8.0
  • Drying Speed - 10% 5.0

Our Verdict

Rivaling our top performers, the Smartwool PhD Pro Light Crew offers immense comfort. Whether your sights are set on multiple week thru-backpacking adventures or a day hike, it is a great option. It features a merino wool-synthetic blend with powerful wicking power and optimized design that thermoregulates over a wide range of temperatures. It has a medium level of cushioning underfoot (even though it's called a lightweight sock) with vents placed strategically on the top of the foot and throughout the shaft. After hiking, trail running, and biking 60+ miles through rain, sleet, and hot weather, it still looks like it just came out of the package! Of all the Smartwool sock options tested, it seems to be the most durable we've encountered. We are not a fan of the massive price tag, but it is one of the best hiking socks that we've ever tested.
Great thermoregulation
Incredibly comfortable
Slow to dry

Our Analysis and Test Results

Performance Comparison

smartwool phd pro light crew hiking socks review - the smartwool phd pro is one of the best out there. it's highly...
The Smartwool PhD Pro is one of the best out there. It's highly breathable, comfortable, and thoughtfully constructed. A good option for day and overnight hikes.
Credit: Amber King


Whether you're seeking a sock that'll provide comfort on a long thru-hike or a day-hike, the Smartwool PhD Pro Light Crew is a wonderful candidate. The cushioning underfoot is plush and plentiful as it spans from heel to toe. It offers enough response that will keep your feet happy, even on days where your milage hits double digits.

smartwool phd pro light crew hiking socks review - a look at the thoughtful and plush cushioning underfoot that offers...
A look at the thoughtful and plush cushioning underfoot that offers protection, even on the most technical trails.
Credit: Amber King

What's more, is the fit is specific and thoughtful. Around the arch is a band of compressive elastic which keeps the sock in place and prevents slippage. The enhanced toe box is streamlined to fit both a man or woman's foot with additional cushioning on the top and sides of the toes. The elastic at the top of the sock is thick and provides a good fit that doesn't slide down while on the trail. Overall, we deem this a comfortable sock that rivals any model we have tested.

Wicking & Breathability

Like any good hiking sock, this one wicks away moisture efficiently and effectively. Some men and women are blessed with a sweatier foot than most which can pose problems on long hikes. We are happy to report that this sock balances ample cushioning with breathability, and offers immense wicking power.

smartwool phd pro light crew hiking socks review - we wore it while running on a hot day in the mountains. the result...
We wore it while running on a hot day in the mountains. The result? Perfection!
Credit: Amber King

Thoughtfully constructed, Smartwool uses less material at the top of the foot and along the shaft of the sock to provide ventilation, even on the hottest days. While we would probably choose a lower cut sock (with less cushioning) for super hot days in the desert, it does just fine on warm summer days. The merino-wool fibers feature big loops that grab moisture from the foot and wick it away to these points of ventilation. The material is tightly packed, increasing the surface area for awesome wicking power.


If you're looking for a great option for colder days on the trail, it delivers. We hiked the whole day in this sock, then wore it to bed on a colder summer evening (40 degrees Fahrenheit) in the mountains. Even though the sock was a little damp from stepping in puddles and getting caught in a rainstorm, our feet stayed comfortable and dry. Even when sleeping (when activity declined), we stayed warm.

While we haven't had the chance to test this new option from Smartwool in winter conditions, we would expect that it would perform well even in colder conditions. This assumption comes from the immense cushioning underfoot and the quality of the materials that this company has.


So far, so good! We've put about 60 miles on these babies and haven't noticed any signs of wear, compaction, or tear! During these 60 miles, we ran through puddles, hiked for 10+ mile distances, and carried weighed down packs for overnight missions. There are no reported issues from online reports (that we have found) either.

smartwool phd pro light crew hiking socks review - a look at the durability after logging over 60 miles on this sock.
A look at the durability after logging over 60 miles on this sock.
Credit: Amber King

Drying Speed

During our drying speed tests, we looked to see which socks dried the fastest both on the trail and in a controlled scenario. Unfortunately, on the trail, we noticed that, while this sock does keep our feet dry, it retains water in the fabric and doesn't dry quickly. When validating this observation with our drying speed tests, we learned that it took about 90 minutes to dry, absorbing about 92% of its original weight when wet. In comparison to other socks out there, this is a slower drying sock, but expected because of it thicker cushioning underfoot.

smartwool phd pro light crew hiking socks review - hiking steep trails? long backpacking trips? this sock will perform...
Hiking steep trails? Long backpacking trips? This sock will perform well through all conditions.
Credit: Amber King


This is an expensive sock! While it does offer impeccable performance with a seemingly durable design, the price tag is a little hard to swallow. There are higher performing contenders out there, with a better money-back guarantee and a lower price. However, if you're a huge lover of Smartwool, and the price doesn't matter as much, this is one of the best hiking socks we've seen from them yet.


The Smartwool PhD Pro Light Crew is a merino wool-synthetic blend sock designed to take on all sorts of backcountry adventures. It offers a medium amount of cushioning underfoot that is suited for both day hikes and gargantuan thru-hiking adventures. It features a durable design that offers a wonderful balance of warmth and breathability. Our biggest caveats? It dries slowly and the price tag is high.

Amber King

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