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(Photo: Brad Kaminski)
It’s easy to get all starry-eyed about a new shell or even a slick, kitted-out bib, but savvy skiers know that true comfort on the slopes starts next-to-skin. Your choice of base layer directly impacts how well you wick away sweat, dump heat, and retain warmth; in other words, the quality of your ski day.
Choosing the right first layer is no longer an easy task. Long gone are the days off waffle-knit long johns that were wetted out after a few freeze-thaw cycles. From natural fibers like merino, bamboo, and even alpaca to synthetic options infused with all the modern technologies, today’s base layers perform better than ever.
Our test crew put 53 items through the wringer last season, from snow-dusted running trails to deep backcountry powder, to bring you our highly honed list of the best base layers on the market right now.

Sizes: XS-4X
Key materials: merino wool
Comfort rating: 9/10
Breathability rating: 7/10
Warmth rating: 9/10
Pros and Cons
+ Luxe feel
+ Durable
+ Inclusive sizing
– No thumbholes
Testers all commented on the softness and the luxurious feel of this 100-percent merino wool top, with one Wyoming-based ski patroller noting that although it felt heavier than her other merino layers, it breathed exceptionally well.
This is one of Smartwool’s beefier tops, designed to be a heavyweight next-to-skin layer for cold days on the slopes, winter camping, snowmobiling, and the like. It also proved more durable than your average merino base layer, as testers wore it repeatedly without feeling the need to treat it with kid gloves. It’s also machine washable, unlike many merino garments.
Our ski patrol tester praised its overall performance, but noted that the extra-long sleeves poked out from beneath her other layers. She also wished there were thumbholes but said this crewneck would still be on the top of the pile for cold-temperature activities.

Sizes: XS-XL
Key materials: polyester/Spandex blend, NASA-developed Trizar technology
Comfort rating: 9/10
Breathability rating: 10/10
Warmth rating: 8/10
Pros and Cons
+ Incredibly breathable
+ Quick-drying and odor-free
+ Made in the U.S.A
– Inconsistent sizing
Hunting brand Forloh is a new addition to our women’s base layer test. Testers complimented the comfort and performance of this top and bottom, even winning over one who typically prefers natural fibers to synthetics. Made with a NASA-developed technology designed to keep astronauts comfortable in fluctuating temperatures, the Deep Space captures body heat and radiates it throughout the layer. As you sweat, its quick-drying material wicks moisture from the skin. “It was surprisingly soft and supple,” said our category manager, who tested it in variable conditions in Banff. “It kept me warm on a couple of super-cold mornings, but also breathed well as the day warmed up.”
Some testers found the sizing to be a little hard to figure out; one, who ordered her regular size (medium), found it a little loose and recommended sizing down if you want a traditional close-to-skin fit.

Sizes: XS-XL
Key materials: merino wool
Comfort rating: 8/10
Breathability rating: 8/10
Warmth rating: 7/10
Pros and Cons
+ Lightweight
+ Hits at boot-top
+ Excellent movability
– Runs a little short
A tried-and-true three-quarter option, Ortovox’s 100-percent merino Rock’N’Wool bottom gives you the barely-there feel you want during a hard-charging tour or in-bounds hike. They were the go-to women’s base layer for one tester who wore them all season, storm-skiing to spring touring, and appreciated the breathability, loose fit, and not having to maneuver ski socks around them. These are a lighter-weight bottom, and some testers who run cold found that they preferred a burlier base layer on the coldest days but picked these out of the pile on high-exertion outing and in temps of about 32 degrees and above. It’s worth noting that if you have long legs, the bottom cuffs might ride up a bit.

Sizes: XS-XXL
Key materials: Royal Alpaca fibers, rayon
Comfort rating: 8/10
Breathability rating: 7/10
Warmth rating: 9/10
Pros and Cons
+ Warm but not heavy
+ Odor-resistant
+ Form-fitting
– Expensive
When it comes to base layers for women made from natural fibers, merino is by far the most readily available. But times are changing: bamboo has made an appearance over the last few years, and now alpaca is making its way onto the scene.
PAKA’s base layers are made with 86 percent Royal Alpaca fibers combined with 15 percent rayon for stretch and comfort. Testers expected the Thermal Crew to be a little coarse, so they were pleasantly surprised to find otherwise. “This alpaca is super soft and very cozy,” commented a Jackson, Wyoming-based tester who wore it throughout the season in mild to moderate conditions. “I’ve tried others that are scratchy and itchy but this feels like a nice sweater.”
In addition to the top’s natural odor-resistance, testers appreciated how the ribbed construction allowed it to hug curves without being too tight or restrictive. Consider PAKA if you’re wool-sensitive, but still want a warm and comfortable natural fiber top for pretty much any winter pursuit.

Sizes: XS-XXL
Key materials: merino, nylon
Comfort rating: 9/10
Breathability rating: 7/10
Warmth rating: 8/10
Pros and Cons
+ Good everyday layer
+ Fun colors and patterns
+ Eco-friendly
– Sleeves run long
Resort skiers looking to suit up in a reasonably priced base layer set should seriously consider the Cedars Midweight top and bottom. Made from responsibly sourced and recycled merino with added nylon for comfort and durability, the Cedar set pleased testers with its performance during bread-and-butter ski days from early winter through early spring—though most agreed that it would be too warm for milder spring-skiing days or high-exertion adventures.
While the Cedar doesn’t break the base-layer mold, it’s solid across the board, with user-friendly details like thumbholes and stretchy underarm gussets on the top and a comfy, wide waistband and flatlock seams on the pants. From an eco-friendly perspective, it’s also nice knowing that the merino is sourced from farms that prioritize healthy animal stewardship.
One tester who wore it while skiing at Utah’s Alta and Snowbird in typical mid-winter temperatures was impressed by the silky-soft material and comfortable fit. “I have a tendency to get a sweaty bottom and these were not itchy at any point,” she said. While the cuffs were comfortable around her thumb, another tester found the quarter-zip’s sleeves a bit too long to fit into her glove, so keep that in mind if that’s a priority for you. The Cedars also come in a crew-neck option at the same weight for $99.

Sizes: XS-XXL
Key materials: polyester, recycled polyester, elastane
Comfort rating: 8/10
Breathability rating: 7/10
Warmth rating: 8/10
Pros and Cons
+ Warm
+ Double as base layer and jogger
+ Pockets
– Not windproof
Not your typical women’s base layer, the FutureFleece Pants are basically a cozy fleece pant with pockets. Testers were surprised that they weren’t too bulky beneath baggier ski pants, and found themselves reaching for them as après lounge companions and weekend errand-wear.
Made from a recycled polyester blend, the pants are cut with a slim fit that testers agreed was flattering. One Jackson, Wyo.-based skier liked the FutureFleece as a warm option for resort riding on the coldest days, where she paired them with a silk-weight layer. The same tester also took them out on the Nordic trails but found that they didn’t offer enough wind protection to wear solo.
If you’re packing light for a ski trip, these can pull double duty as a travel pant and a base layer. “I like that I could wear it under my ski pants but also feel comfortable wearing them to the grocery store.”

Sizes: XS-XL
Key materials: Merino wool, polypropylene
Comfort rating: 9/10
Breathability rating: 10/10
Warmth rating: 8/10
Pros and Cons
+ Two-layer construction ideal for wool-sensitive people
+ Excellent moisture management
+ Flat seams are chafe-free under other layers
– No thumb holes
Helly Hansen’s two-layer LIFA merino tech, which sandwiches an internal synthetic layer with an external merino layer, allows folks who are wool-sensitive to experience the material’s benefits. The result was a hit among our testers, who uniformly felt that LIFA’s combination of warmth and breathability made this the ultimate base layer for any winter activity where big temperature fluctuations require the need to stay warm and dry.
While testing this set in regions ranging from the Northeast to the Tetons, testers agreed that the LIFA Merino Midweight crew top and bottom provided warmth on lift rides and windy summits but also wicked moisture extremely efficiently. One tester who happened to have it on while digging out her snowed-in van was impressed with how dry she stayed throughout the physical exertion. For folks wanting even more ventilation, HH makes a zip-neck version for quickly dumping heat.

Sizes: XS-XXL
Key materials: Merino wool, nylon, spandex
Comfort rating: 9/10
Breathability rating: 9/10
Warmth rating: 8/10
Pros and Cons
+ Super stretchy and comfortable
+ Thumb slits and ponytail hole
+ Doesn’t get stinky
– Baggier fit might not be ideal as a ski base layer
Although Janji considers its Rover hoodie to be a midlayer, this incredibly stretchy and comfortable merino-blend top might be the ultimate versatile hooded long-sleeve shirt. Weighing in at 10.6 ounces, the Rover Merino Hoodie is a true midweight base layer for all winter pursuits, but where it excelled the most during our test was as a running top for a wide range of conditions. Made mostly from merino wool and nylon with a pinch of spandex for added stretch and ease of movement, the Rover pulls on and off easily and feels weightless during your runs, yet adds just the right amount of warmth on cooler mornings and dumps heat effortlessly as your motor gets going.
Testers appreciated thoughtful features including the wide and stretchy thumb slits on the sleeves, a ponytail hole on the snug hood, and a small zipper pocket on the lower hem for stashing coffee money or a house key. I found it to be a fantastic addition to my winter running kit, and I especially appreciated the fact that it literally never got stinky. It’s become my go-to fall and winter running top.

Sizes: XS-L
Key materials: Nuyarn Merino Wool Blend with Bamboo
Comfort rating: 10/10
Breathability rating: 8/10
Warmth rating: 9/10
Pros and Cons
+ Great loft and breathability
+ Super warm
+ Stretchy and comfortable
– Pricey for base layer bottom
Lé Bent waffle-knit leggings use the brand’s tried-and-tested Nuyarn construction, which means the wool fibers are spun around a bamboo filament, rather than coiled, as with traditional merino. The result is more surface area to soak up and diffuse moisture, which leads to a garment with more loft, better temperature regulation, durability, and superior breathability.
Our testers raved about these bottoms, with one Vermont skier admitting that they kept her as warm on the coldest days as her trusty pair of down-insulated crops. “A bit bulky,” she commented, “but worth it for the warmth.”
Classified as midweight, the Sentinel uses a waffle-knit design to reduce the weight without sacrificing the performance. The full-length tight is a bit of splurge for a base layer bottom, but testers argued that it’s a luxury purchase with best-in-class thermoregulation. In other words, you get what you pay for. “OBSESSED with this baselayer,” said our 5-foot, 6-inch tester. “I toured in it and never got too hot. My butt never got cold at the resort, even on the coldest and wettest days.”

Sizes: XXS-XL
Key materials: Polartec Power Grid synthetic fabric
Comfort rating: 9/10
Breathability rating: 8/10
Warmth rating: 8/10
Pros and Cons
+ Excellent warmth-to-weight ratio
+ Breathable in a range of conditions
+ Deep chest zipper, thumb loops, and stretchy underarm gussets
– Not offered in a hooded option
Given the heft of Patagonia’s beefiest base layer, we expected it to be less breathable. But while the Capilene Thermal Weight Zip Neck and Bottom is the warmest in the brand’s lineup, our testers were pleasantly surprised by how well this set was able to dump heat, wick sweat, and keep them dry and comfortable throughout a large range of conditions.
Patagonia uses Polartec Power Grid, a lofted synthetic technical fleece that layers a wicking fabric next to your skin to soak up moisture with a top layer that easily disperses it. The “grid” design creates air channels that help keep the base layers light and breathable. “This is a wonderful layer and was often my go-to this winter because I knew it could handle many different conditions and would be the most comfortable,” said one tester who wore it in temperatures down to 5 degrees on shifts as a volunteer ski patroller at Grand Targhee.
Testers also appreciated the substantial layer’s versatility, allowing them to not only bundle it beneath many layers for warmth on the coldest days but also wear it under just a light shell on the skin track or other active pursuits, where they said it performed equally well. Another tester just replaced her set after eight years of consistent wear. “The durability is impressive given the breathability,” she said.

Sizes: XXS-XL
Key materials: Polartec Power Stretch Pro
Comfort rating: 9/10
Breathability rating: 7/10
Warmth rating: 9/10
Pros and Cons
+ Warm and cozy
+ No inside leg seams
– Waistband could be wider
– Runs a little long
When warmth is of the utmost importance in your base layer, Houdini’s Power Tight has got you covered. Literally. They’re stretchy, insulating, breathable, and oh-so-cozy—so much so that testers wore them all day then slept in them on winter camping trips in Utah and Colorado.
Made from Polartec Power Stretch Pro, a dual-layer synthetic fabric with four-way stretch that wicks moisture from the skin and disperses it up and out for quick evaporation, the Power Tights were a go-to pick for our testers all winter. The next-to-skin layer feels cozy like fleece, and the outer layer is silky smooth, making it easy to pull on your shell pants. Testers loved that the Houdini Power Tights have no inside leg seams, so chafing is never an issue, but agreed that a wider waistband might be more comfortable when you’re wearing these around the clock.
Testers who skied in the Power Tights said that they’re quite warm, and advised pulling them out on colder, lift-riding ski days. But for winter camping, all agreed that these were a staple and worth every penny. “I wore them camping early spring in Moab and I was so thankful to have them.”

Sizes: XS-XL
Key materials: Merino wool
Comfort rating: 10/10
Breathability rating: 8/10
Warmth rating: 7/10
Pros and Cons
+ Well-priced base layer staple
+ Super soft next to skin
+ Built-in SPF 30 sun protection
– Runs big
Anyone shopping for a high-quality merino base layer for skiing that won’t break the bank should seriously consider REI’s lineup. Made with 100-percent ultrafine 185-gram merino wool, this layer provides warmth and next-to-skin comfort without any itchiness or chafing. Flat seams and underarm and crotch gussets to enhance your comfort and range of movement, while the super stretchy waistband is low profile beneath ski pants. (The top is available as a crew neck or a half-zip depending on your personal preference.)
Our testers wore this at resorts as well as on winter hikes and snowshoe excursions, and felt that it got the job done, albeit without any bells and whistles like thumb holes or built-in UPF protection. This would be a good choice for someone with basic long underwear needs who want a quality option that isn’t flashy or fancy,” said one Durango, CO-based tester who wore it in a range of conditions last winter. “I was surprised by how soft the material was. I didn’t notice or feel it while skiing, hiking, or cross-country skiing. After a big sweat, it dried before the chill set in.”

Sizes: XS-2XL
Key materials: Merino wool, nylon, spandex
Comfort rating: 9/10
Breathability rating: 8/10
Warmth rating: 7/10
Pros and Cons
+ Simple design
+ Built-in SPF 50 sun protection
+ Comfy, wide waistband with a hidden pocket
– Best for moderate temperatures
In addition to performing well during winter backpacking trips to and fro in temperatures ranging from 10 to 60 degrees, our testers loved that these women’s base layers looked and fit like sporty tops and leggings rather than winter long johns, and that they have UPF 50 sun protection built-in. The Woolverino midweight bottoms feature a yoga-style wide waistband with a small stash pocket and a compression-style silhouette. They are made with a blend of merino wool, nylon, and spandex so they will keep their shape even if you wear them hiking all day, sleep in them, and then wear them to breakfast the next day. The Henley top is made from 100-percent merino wool with a regular fit and flatlock stitching so it’s comfortably worn with a backpack and doesn’t bunch up or rub on your shoulders. The three-button front-closure style adds a bit of flair and airflow while the slightly longer sleeves and hemline add to its classy profile.
When shopping for women’s base layers, consider how they will perform when you’re out in the wild. First and foremost, are they comfortable? These are your next-to-skin layers so they need to feel good on your body. Are the seams compatible with backpack straps? Does the hem work well with your ski pants? Does the half-zip, button-up, mock neck, or crew neck satisfy your style? Are you looking for something to wear during long days of uphill travel in the backcountry or will you be spending the day riding chair lifts?
Merino wool fibers are naturally odor-resistant, moisture-wicking, and breathable, but generally less durable as synthetic materials. Because synthetics are usually a blend of fabrics, they are popular with those keen on stretchiness and moisture management. It’s better to buy something that is thoughtfully designed and durable rather than something cheaply made that might fail you on the mountain. Beyond the technical details, you may also want to determine if what you are buying is sustainably produced. Most reputable brands have information about their sustainability practices available on their websites.
Understanding that base layer testing can be highly subjective based on personal preference, body type, activity level, and a host of other factors, we assembled a test team of ladies of all different shapes and sizes, living in different mountain regions, who regularly get after it no matter the winter weather. Category manager and SKI Executive Editor Samantha Berman lives and plays in Colorado’s Front Range, where she skis most weekends at the I-70 resorts. Other key testers include a Wyoming ski patroller, an Arizona-based social media director, and Outside’s Gear Director.