The Best Men’s Base Layers of 2024

A case can be made that base layers are the most important and underappreciated piece of a layering kit. Because it’s the layer that sits on your skin, it’s also the first line of discomfort should it prove itchy, scratchy, or not wick moisture well. Therefore, the perfect base layer goes unnoticed, while a subpar one is obsessed over and complained about. Every layer below will serve you well, in a low-key fashion, through the winter thanks to heavy vetting from Outside’s group of crack testers.

The Winners at a Glance

• Editor’s Choice: Rab Conduit Crew
• Nathan Dash Long Sleeve Tee
• Beyond Bask L1 Long John
• Smartwool Intraknit Thermal Merino Base Layer Crew

The Reviews: The Top Men’s Baselayers of 2024

Editor’s Choice: Rab Conduit Crew ($75)

Weight: 6.9 oz
Sizes: S-XXL
Key Material: Recycled polyester
Best For: Versatile layer for all outdoor winter adventures

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In spite of the widely different range of tester expectations, sports, and geography—the Conduit was a unanimous tester favorite thanks to its extreme comfort and wide usable temperature range. After months spent skiing at Sugarbush and mountain biking around Burlington, Vt., tester Greg Durso’s notes on the Conduit were simple. “Rab just seems to have the best materials,” he said. Testers unanimously agreed that there must be some form of alchemy in the 92-percent recycled polyester eight-percent elastane weave that manifested in a lightly gridded fleece backer. It received top marks all along the temperature range—it was called “comfortable” by testers in temps around the tens in sideways snow in central Oregon under some layers all the way up to a 40-degree overcast long-run on its own in the Ashland, OR watershed. Even though it was on the heavy side for the top end of our temperature range at 6.9-oz, the micro-channeled gridded moved excess heat with aplomb. “It was great at wicking moisture,” noted Brett Hornig after taking it on a double digit length run in 45-degree temps with a pack.

Bottom Line: For one layer that you can rely on all season long, look here

Nathan Dash Long Sleeve Tee ($55)

Weight: 6.9 oz
Sizes: S – XXL
Key Material: TriDry, lightweight combination of nylon, polyester, and elastane
Best For: Ski touring, winter trail running

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“This shirt is actually great,” gushed Hornig after taking the Dash Long Sleeve Tee out on an unseasonably hot 50-degree trail run. Nathan’s “TriDry” knit—which is a lovely amalgam of nylon, polyester, and elastane fibers—wicked moisture with such efficiency that skimo nerds, trail runners, and pow-hungry resort skiers all noted how dry their skin felt during their highest intensity activities while wearing the Dash. It was also comfortable as hell next-to-skin. “More comfortable against the body than most ‘natural’ fibers,” Hornig said after a trail run in Ashland, Oregon’s watershed. It was a winner very off-piste as well—receiving top marks both as a pajama top and a swing piece to wear to the bar after a cold evening run. ”Super soft fabric and a great fit,” Hornig said.

Bottom Line: The layer for high-output activities in warmer temperatures

Beyond Bask L1 Long John ($70)

Weight: 5.8 oz.
Sizes: S-XXL
Key Material: Polartec Power Grid
Best For: Warmth and comfort during winter ski adventures

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One tester wore these bottoms while taking adaptive ski instructor training outdoors during an inclement stretch at Mt. Bachelor for over 50 hours over eight days. The impressiveness of this fact is threefold: 1) the bottoms were not horrifyingly stinky on day eight 2) they moved well enough to not get on the tester’s nerves during a grueling outdoor work week 3) they remained comfortable throughout all 50 plus hours. Credit the top comfort marks to the the 3.5-ounce Polartec Power Grid Fleece which was lightweight to keep moisture moving from the tester’s undercarriage. It also stretched enough that it could accommodate a tight athletic fit that never bunched through long days. The flat-seam contoured construction furthered the lack of pinch points on these long johns making them the preferred bottom of this testing block. A note on fit: they are quite tight so think of sizing up if you are in between sizes.

Bottom Line: An excellent option for long days or multi-day tours

Sponsor Content
Arms of Andes Alpaca Wool Hoodie ($145)

Lightweight and made with 100 percent royal alpaca wool, this hoodie from Arms of Andes is an essential in every layering system. Whether you’re hiking in the springtime or snowshoeing on a cold winter day, alpaca wool has the perfect balance of warmth and breathability for year-round wear. With the soft, itch-free feel of alpaca wool against your skin, you’ll never go back to Merino again. Plus, the half-zip design, fitted hood, and soft felt-resistant fabric look good on and feel even better.

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Smartwool Intraknit Thermal Merino Base Layer Crew ($130)

Weight: 7.3 oz
Sizes: S-XXL
Key Material: Merino wool blend
Best For: Ski touring and other high-output endeavors

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Smartwool made the (ahem) smartest 3-D knit baselayer we have ever tested in the Intraknit. The premium wool company used the technology to seamlessly weave in mesh in high heat spots like under the armpits and an extra amount of stretchy elastane in high movement areas to areas like the creases of our arms to make a piece that moved and breathed like a living organism. Testers remained in amazement of this franken-movement throughout varied athletic needs—in everything from multi hour trail runs to 50-minute high intensity freezing ski tours at night. It also happened to be damned comfortable. The 53-percent merino wool, 45-percent polyester, two-percent elastane received top marks in next-to-skin suppleness after a high intensity trail run with over 1,000 feet of elevation gain and 45-degree temps. “Very soft and stretchy material. Comfortable against the body and not scratchy,” Hornig wrote.

Bottom Line: Best for staying comfortable when you’ll be moving your body—a lot

How to Buy Men’s Baselayers

Comfort is paramount when purchasing base layers. Every body and every skin type is different so dialing in the materials that feel the best on your skin is the most important part of the base layer buying journey. The most advanced, wildly fancy micron, merino wool material can make someone with a wool intolerance miserable.

Once you have landed on a material that works for your skin, start looking into moisture movement. If you sweat a ton, as many of the testers for this category do, look into lightweight synthetic base layers as they have an excellent track record for moving moisture efficiently. If you do not sweat much then you can get away with thicker next-to-skin layers.

How We Test

• Number of Products: 38
• Number of Testers: 5
• States Tested In: 5
• Temperature Range: -3 to 55 F

While the communication process varied from remarkably detailed notes on google documents (Hornig) to handwritten notes over giggles and beers (Durso), the testing process itself was uniformly all business. Our team put in hundreds of miles run, ridden, and skied in conditions ranging from sub zero mid mountain whiteouts to mild seaside runs.

Meet the Testers

Category lead Joe Jackson has been testing base layers for Outside for a decade. On top of his usual regular ski tours, winter trail runs, and mandatory sleep-in-layers testing he worked weekends as an adaptive ski instructor on Mt. Ashland where he got to know each layer intimately during his seven hour shifts in the elements. Ultra Running Coach, Trails and Tarmac owner, running shoe reviewer, and podcaster Brett Hornig put down well over 100 running miles testing layers in wintery conditions. Greg Durso, Program Director for The Kelly Brush Foundation is one of the hardest charging, most prolific, adaptive ski and mountain bike athletes on the East Coast.