8 Women’s Base Layers Our Gear Editor Loves
From onesies to tanks, these performance delicates will keep you comfortable

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Base layers are some of the most crucial and most used items in any adventure wardrobe. They wick away moisture to keep you dry, and you can take them from trailhead to summit (and sometimes back into your sleeping bag) without needing to change. Here are some of our favorite women’s models, from warmth-trapping winter layers to breezy warm-weather pieces.
Icebreaker 200 Zone One Sheep Onesie ($220)

Steeze aside, one-piece base layers are ideal for frigid missions: no more exposed spots from your top riding up. Icebreaker’s merino version features mesh panels under the arms and behind the neck, shoulders, and knees for breathability and a long zipper for fuss-free bathroom trips.
Smartwool Merino 150 Base Layer Tank Top ($65)

This buttery-soft piece is form-fitting enough to layer but loose enough to wear alone. Hike in it, throw a fleece over it, fall asleep in it.
Fabletics Tess Warp SculptKnit Bra ($35)

The full-coverage design is forget-you’re-wearing-it comfortable, courtesy of a wide chest band that doesn’t dig in. Loose mesh panels at the upper chest and down the back help manage moisture.
Ridge Merino Inversion Midweight Leggings ($55)

When the temperature drops but your pace doesn’t, these full-length bottoms are the ticket, offering just the right amount of warmth to get you out the door but not so much that you’ll overheat five minutes up the skin track. The exposed-elastic waistband minimizes bulk.
ExOfficio Give-N-Go Sport Mesh Hipkini Underwear ($24)

The Hipkini offers full coverage in the back without the high rise of traditional briefs. The mesh fabric is silky smooth and wicking for all-day comfort.
Oiselle Wazzie Wool Shirt ($96)

This midweight long-sleeve top offers a flatteringly close fit and generous length, enough to tuck into your ski pants. Thanks to wool’s antimicrobial properties, no one will be able to smell—err, tell—that you’ve been wearing it four days in a row.
Lululemon Energy Bra ($52)

The Energy is the Goldilocks of support systems, providing enough compression (even for full-chested women) for a 20-mile run without smothering or fitting like a corset. Perhaps most significantly, unlike most supportive, D-cup-friendly bras, this one is cute enough that you’ll be excited to wear it on its own.
Craft Fuseknit Comfort Boxers ($30)

A mid-thigh inseam makes the Fuseknit Comfort ideal for days that aren’t cold enough for full-length long johns. A wide, flat waistband and seamless knit construction deliver premium comfort.