Our editors independently research, test, and recommend the best products and services; you can learn more about our review process here. We may receive commissions on purchases made from our chosen links.
Best Overall: Patagonia Capilene Midweight Crew at Backcountry
"With a mid-weight fabric and approachable price point, this is the Goldilocks of base layers."
Best for Men: Helly Hansen Lifa Merino Crew at Amazon
"Has a fiber inner layer that's great for active men who tend to run hot and work up a sweat."
Best for Women: Kari Traa Women’s Rose Half-Zip at Amazon
"The form-fitting fabric is tailored specifically for women's bodies."
Best for Kids: L.L. Bean Wicked Warm Midweight Underwear Set at L.L. Bean
"L.L. Bean's base layer set has an affordable price point so you can replace them each season."
Best for Summer: REI Co-op Lightweight Base Layer Crew Top at REI
"Even in summer, this crew delivers a season-appropriate level of protection and breathability."
Best for Skiing: Smartwool Merino 250 Base Layer Crew at Amazon
"With flatlock seam construction, this top won’t chafe, even when worn under a snow jacket all day."
Best for Cycling: Outdoor Research Enigma Half Zip at Amazon
"Thumbholes slip over your hands to help stave off the chill while you're holding handlebars."
Best for Winter: Seirus Heatwave Reversible Long Sleeve Crew Top at Seirus
"Kinetic properties help raise your temperature, so you'll be toasty even in the harshest winter conditions."
"Under Armour delivers flexibility in spades via this lightweight, affordable base layer."
The outdoors can indeed be great—as long as you feel well outfitted. That comfort begins with base layers that keep you warm, but not overly hot, whether you’re winter camping at a national park, skiing, skating, or sledding in Canada’s playground. But there are lots of options available, so we rounded up our top picks to help you find the best ones for any activity.
Read on for our picks of the best base layers available.
Our Top Picks
Best Overall: Patagonia Capilene Midweight Crew
With a mid-weight fabric and approachable price point, the Patagonia Capilene Midweight Crew is the Goldilocks of base layers. The product’s versatility spans leisure to active pursuits, and from moderate to cold temperatures. Patagonia has swapped merino wool, a traditional material in base layers, for 100 percent recycled polyester, which makes this top eco-friendly. Going synthetic sacrifices some of the odor absorbing benefits of the natural product; however, Patagonia has applied a fabric treatment that assists with odor control and adds to the crew top’s longevity. The fabric also offers superior moisture wicking, so you won’t find yourself chilled after finishing a hike from sweat clinging to the shirt. A women’s version is also available.
Best for Men: Helly Hansen Lifa Merino Crew
Helly Hansen combines merino wool and synthetic fabrics for a dual-layer construction that offers the best of both worlds. Helly Hansen’s original LIFA fiber inner layer adds warmth while pulling moisture away from the skin. That’s especially important for active men who tend to run hot and work up a sweat. The outer merino wool layer adds odor-resistance and additional insulation. As a midweight garment, this is suitable for colder weather or more easy-going activities in milder temps. Helly Hansen makes a women’s version of this top as well.
Best for Women: Kari Traa Women’s Rose Half-Zip
This pure merino wool base layer has all the function and style women seek. Kari Traa picked superfine anti-itch merino with plenty of stretch, so these base layers offer plenty of insulation while not feeling constrictive. The form-fitting design is also tailored specifically for women’s bodies. Thinner under-arm side panels and a half-zip pullover design allow women to cool off quickly if they heat up during active pursuits. Plus, the snowflake patterned fabric, contrast stitching, and bright colorways will appeal to fashion-minded women—even if the only ones seeing these base layers are themselves.
Best for Kids: L.L. Bean Wicked Warm Midweight Underwear Set
This shirt and pant set will keep kiddos warm without breaking the bank. Made of synthetic polyester, this set won’t itch. The midweight fabric is well suited for layering under snowsuits—without being so heavy your kid will end up looking like the main character from The Christmas Story. L.L. Bean offers sets for infants, toddlers, and older children with slight modifications for each age group. The set also has an affordable price point, so you’ll easily be able to replace these layers for fast-growing kids each season.
Best for Summer: REI Co-op Lightweight Base Layer Crew Top
Made of a lightweight polyester blend, this top will keep you well insulated in mild conditions. Even in summer, conditions such as thunderstorms, wind, and cool evenings can call for layering up, and this crew delivers a season-appropriate level of protection and breathability. With a bit of Spandex blended into the fabric, this garment has a four-way stretch that’s perfect for hiking, climbing, sailing, and any other seasonal activities. UPF 50+ sun protection also makes this a summer-friendly single-layer top. Fast-wicking polyester keeps sweat from settling on the skin and helps the crew dry quickly. REI Co-op makes a men’s version of this top as well.
Best for Skiing: Smartwool Merino 250 Base Layer Crew
Perfect ski trips don’t start and end with fresh powder. Your layers are important for keeping you comfortable on the slopes too. Made by Smartwool, a pinnacle brand in the world of base layers, this merino-wool crew is a crowd pleaser. Interlocking knit fabric enhances the natural comfort, breathability, and moisture wicking qualities of the merino wool. That makes this base layer a fitting pick for active activities, such as skiing. Plus, with flatlock seam construction, this top won’t chafe, even when worn under a snow jacket all day. Smartwool makes a women’s version as well.
Best for Cycling: Outdoor Research Enigma Half Zip
This lightweight layer was designed with active pursuits in mind. With a close fit, this layer won’t feel bulky on rides, whether it’s serving as a single or base layer. Thumbholes help keep sleeves secure if you’re layering up, or slip over your hands to help stave off the chill while you’re holding handlebars. Quick-drying, odor-resistant wool makes this top breathable; however, if you’re feeling overheated, simply unzip the 12-inch front zipper for instant relief. Shop the women's version here.
Best for Winter: Seirus Heatwave Reversible Long Sleeve Crew Top
Whether you’re snowmobiling or winter camping, cold-weather conditions call for serious insulation. Seirus, a leader in heated gloves and hats, delivers great protection with its base layer via heat-reflective technology. Kinetic properties help raise your temperature four to five degrees while Heatwave™ technology helps reflect 20 percent of escaping body heat back to you. All that adds up to a warm core that will help keep your extremities toasty even in the harshest winter conditions. Anti-chafing and anti-microbial technologies add to the benefits of this top. Seirus makes a men’s version of this base layer as well.
Best Value: Under Armour ColdGear Long-Sleeve T-Shirt
Under Armour is made to move, and the brand delivers flexibility in spades via this lightweight, affordable base layer. A polyester-blend fabric lends this garment warmth, moisture-wicking, and quick-drying qualities. The addition of elastane gives this top impressive mobility. It stretches in every direction and moves with you, whether you’re cross-country skiing or building an epic snowman.