Sure, stylish coats and jackets get all the buzz this time of year as temperatures drop and flurries dust the mountaintops, but we’re here to tell you that the best base layers deserve some love too. In recent years, brands have introduced a whole slew of fun prints and buttery-soft fabric blends into the once-bland world of base layers, making the category anything but boring.
Experts recommend a three-layer strategy for frigid romps in the outdoors: a base layer as your next-to-skin garment, then a mid-layer (like a fleece or a fitted, insulated jacket), with a thick, wind- and weather-resistant shell on top. If it’s really cold or you’ll be sitting still in freezing temperatures for extended periods, toss a down puffy on over your mid-layer.
We asked a number of our favorite outdoor professionals and big-time adventurers what their top picks are for this season’s base layers. The result is a robust list of the best base layers out there.
Best base layer tops
A good base layer shirt needs to do a lot. While properly insulating your core, it should also wick away moisture when you sweat, stay ventilated in your warmest zones and (ideally) not stink up after a single day of use. Below are a bevy of tried-and-trusted base layer tops ranging from thick hoodies (ideal for the chilliest days) to lightweight crew necks (for more active pursuits like uphilling, splitboarding and trail running).
“The Arc’teryx Rho base layer is about as buttery soft as base layers come,” Erica Zazo, a freelance writer and frequent contributor to CNN Underscored, says. “The front pocket is sleek and perfect for holding a couple of credit cards when you don’t want to carry a bulky wallet. I also find I don’t have to wash this base layer very much, as it doesn’t trap in smells.”
This lightweight (9.3 ounces) garment is designed for active pursuits in cold temps. Check out the Rho Heavyweight for a more insulated option.
A rarity in the base layer world, this set by Revolution Race allows buyers to save a little cash on high-quality merino wool by purchasing a matching top and bottom at the same time. Adventurer and host of the Discovery series Hidden Frontiers, Reza Pakravan, says the Revolution Race Fuse base layer set “stands out as my ultimate favorite.”
“When traveling to cold destinations, the importance of the base layer cannot be overstated, as it effectively manages moisture, enabling you to stay comfortably warm,” Pakravan added. “I recently put this to the test during an expedition to the mountains and desert of Neom, Saudi Arabia, where nighttime temperatures dipped close to freezing.”
Not only is this light, synthetic base layer affordable but it’s top of the list for journalist and travel writer Sarah Kuta, who loves it for active winter adventures in Colorado and beyond.
“When I sweat,” Kuta explains, “it wicks away the moisture and keeps my body temperature super comfortable.”
Avid skier and editor of Elevation Outdoors Magazine, Doug Schnitzspahn recently fell in love with European brand Uyn’s all-natural base layers. “These base layers are for those who like an athletic (read: tight) fit and seek high performance.”
“They get the job done whether you are knocking out speedy laps at a resort, uphill skiing on a skin track or even just winter running,” Schnitzspahn says.
Writer and adventurer Bernadette Rankin says her favorite base layer top is Smartwool’s Intraknit Thermal Max Quarter-Zip, and for ultra-cold snow days, I’m inclined to agree. Thicker than your average merino crew, this design is warmer too, without ever feeling bulky.
“Thoughtful engineering and 3D mapping combine forces to deliver just the right amount of warmth during a hiking break to Colorado’s Longs Peak, dial back the heat for that final push and look ‘oh so cute’ for that must-have celebration summit selfie,” Rankin says.
Big-mountain adventurer and author Heather Balogh Rochfort says that Minus33’s Ossipee Women’s Crew is her “best bargain” choice for merino base layers. “The Ossipee is a solid option because it has a nice hand for a midweight, fits well and doesn’t break the bank. It’s a no-frills top without fancy patterns or zippers, but I think that’s more than worth the savings,” Balogh Rochfort explains.
Like the Ossipee, the Chocorua is a great value for a merino wool layer. Made by a New Hampshire company that knows its way around the cold, this midweight top is every bit as soft and cozy as its more expensive competitors.
Maybe it’s my vanity or my love of great design talking, but I’m obsessed with Kari Traa’s plethora of adorable (and functional) merino wool base layers, like this Scandinavian-style Rose Half-Zip top. Designed in Norway by women, for women, the brand proves that you can look chic while shredding hard on the slopes this season.
“I’m a big fan of Ibex’s merino wool gear, including the brand’s ultra-warm, surprisingly soft base layers,” CNN Underscored editor Kai Burkhardt says. Apart from being naturally antimicrobial (meaning that it won’t smell funky after a day out), this Woolies Pro Tech long-sleeve top is knit with a nylon core for extra durability and longevity.
“This has been my go-to base layer for snowboarding, camping and basically any other time I’ve been in cold weather,” Burkhardt says. “I wore these base layers every night on several week-long camping trips and they never smelled gross.”
“I’ve owned this hoodie for a couple of years, and I’d argue it’s one of my most-worn items,” Balogh Rochfort, who’s also a frequent contributor to CNN Underscored, says. “I’ve taken it everywhere from backcountry skiing in Colorado to resort skiing in California and mountaineering in Washington. The wool is exceedingly soft, and I like the trim fit because it easily fits over a tank for more of a base layer vibe, but it can also be worn on its own over top of a sports bra.”
With a full-length zipper and next-to-skin fit, this wool hoodie keeps wearers toasty while also being easy to vent as needed. It’s available in seven colors as of this writing with sizing up to XXL.
For those who simply can’t stand wool and prefer a warm, cozy synthetic layer that’ll stand the test of time, check out Patagonia’s entire line of Capilene thermals. I’ve had one in my closet since 2017, and after heavy use in the backcountry (including a stint on the John Muir Trail), it’s still going strong.
Rankin loves Patagonia Capilene offerings because they dry quicker than merino too. “[It] dries out by the time it’s my turn to call ‘climb on’ for the next round of that type-two rock-filled fun,” she says.
Best base layer bottoms
Though a bit simpler in their features than most base layer tops, thermal bottoms still need to be sweat wicking, thick enough to insulate in the coldest temps, stretchy enough to survive alpine climbs and durable enough to last many seasons in the wilderness. Below are our experts’ picks.
“No matter what my day of adventures has in store for me, I trust that the next-level technology used to create Smartwool’s Intraknit Thermal Max Merino Base Layers will regulate my warmth and elevate my physical efforts,” Rankin says.
Designed with body-mapped mesh ventilation to keep you cool where you need it most and toasty where it matters, this is Smartwool’s most advanced base layer yet.
Avid hiker, skier and national parks adventurer Jen Nelson says that Merino wool is her favorite material for base layers, and this 185 Base Layer Bottom from REI Co-op is an affordable way to get that moisture-wicking, antimicrobial magic at a fraction of big brand prices. “All the warmth and none of the itch! Plus, it’s naturally odor resistant,” she says.
Select sizes of both the men’s and women’s versions of the Merino 185 bottoms are discounted at REI, including the Sea Forest colorway for men.
Want to stay crazy warm on those insufferably chilly lift rides this winter? Grab a pair of Arc’teryx’s Rho Heavyweight Base Layer Bottoms, which Chicago-dweller Zazo says are her favorite for true winter weather. “The best part about these pants is the waistline that doesn’t constrict my hips or stomach. Instead, it’s super stretchy with a wide width, giving tons of movement. I also love wearing them around the house to stay cozy in fall and winter,” she explains.
Available in four colors and five sizes, the Rho Heavyweight Bottoms are Arc’teryx’s warmest base layer pant. Don’t overlook the small zippered thigh pocket.
Touting average base layers as “mostly useless,” Flylow has created a new midweight jogger that’s as cozy when waltzing around the cabin as it is under a bib or pair of ski pants on long, frigid powder days. Created with gridded fleece, a zippered security pocket and a drawstring waist, these breathable pants are the ultimate in active loungewear.
Sometimes, you simply don’t want the bulk (or the seams) of a full-length base layer pant inside your ski boot, which is why Balogh Rochfort picked these as her favorite bottoms. “I’ve pretty much never paid attention to my bottom base layers, other than avoiding anything full length because those bunch up with ski boots. Then I found these short pants, and I’m obsessed,” she says. “The cut is great since you don’t have to deal with ski boot bunching, but they’re also crazy warm, thanks to merino fleece in carefully placed areas.”
High-end men’s boxer brand Bn3th is also making sturdy base layers this season, and travel and culture writer Keith Langston loves them for their sustainably sourced merino, antimicrobial properties and sweat-wicking ability. “The best part of Bn3th is the brand’s patented ‘ball pouch’ design. Instead of having a constricting and tight fly-zone, Bn3th’s underwear all come with a spacious pouch area so your boys can rest comfortably,” he says.
Every time I put on a pair of Artilect thermals, I’m truly amazed at how warm and durable they are, compared to how thin the brand’s Nuyarn merino fabric feels.
Designed in Boulder, Colorado, using superfine non-mulesed Australian wool, this midweight bottom features flatlock seams to prevent chafing and a gusseted crotch for freedom of movement on your wildest adventures.
An excellent synthetic option for thermal leggings, Patagonia’s sustainably made Capilene Midweight Bottoms are created with 100% recycled polyester and come equipped with HeiQ Pure odor control, which helps keep stinky microbes at bay, a rarity in non-wool fabrics.
“Patagonia has long been a legend in the base layer game, with a wide array of trustworthy synthetic layers that wick away sweat during my big sends up sketchy Squamish, British Columbia rock-climbing routes,” Rankin says.
Best base layer underwear
Lastly, if you’ve got big plans in the mountains this season, you’ll likely want to layer moisture-wicking, antimicrobial pieces under your kit. Here are a few of our favorite underwear picks designed to keep your precious bits insulated this winter. These ain’t your grandma’s wool undies.
Naturally odor-resistant and moisture wicking, these super-soft merino boxers are constructed with a lay-flat elastic waist and thoughtfully placed seams that help eliminate chafe when you’re out and about. Plus, they’ve got a functional fly so you can stay warm when you’ve got to go in the snow.
A no-ride elastic band sits low on the waist for a soft, comfortable feel. Antibacterial merino provides odor resistance and moisture-wicking properties. Plus, these undies range in sizes from XS to XXL and come in seven colors.
Made with that perfect blend of mesh and Nuyarn merino that perfectly vents where you’ll need it most, Artilect’s Boulder 125 Hot Pant is a full-coverage undie designed with skiing, snowboarding and mountaineering in mind.
The Nuyarn fabric of the Boulder 125 Boxer Briefs possesses significant stretch and recovery to give guys the support they need but also the softness and moisture management to keep things fresh.
This pair of Smartwool Intraknit Hipsters is so silky smooth that I could hardly believe they’re merino when I first put them on. Made with super-fine wool fibers, lyocell, nylon and elastane, this stretchy, low-cut design is great for both summertime hiking and carving up the slopes.
These boxer briefs use Smartwool's Intraknit material, which combines Merino wool and Tencel Lyocell, for the perfect balance of comfort and performance.
Musician and Colorado hiker Oliver Franklin loves the patented BallPark Pouch in these Roast Master Midweight Boxer Briefs by Saxx. Built to cradle your parts like a hammock, this garment is made with a textured knit fabric that helps trap in heat while remaining wonderfully sweat wicking.
I love this longer pair of women’s boyshorts by New Hampshire brand Minus33, because it doesn’t chafe around my upper thighs like skimpier designs do. Durable, antimicrobial and naturally moisture managing, my pair is over two years old and they still look good as new.
The men’s boxer briefs use the same blend of merino, nylon and spandex, which promises moisture-wicking properties and durability.
Seeking that perfect undershirt to wear under your mid-layer or winter sweater? Try Ibex’s Women’s Essentials Racerback, which offers a relaxed fit and is naturally thermoregulating, thanks to its fine merino wool fabric.
Guys, don’t fret. The brand also makes a fab Paradox Short-Sleeve Tee, if you’d prefer a wool undershirt while riding this winter. It's cooling, soft and made with a nylon core for durability