With a form-hugging fit, the Smartwool Classic All-Season Merino Lace long-sleeve tee is a great first layer for high-energy activities—like hiking, jogging or rowing crew—in cool or warm weather.

Underwear TopsBase Layer Tops

Made from a lightweight jersey, the women's Smartwool Classic All-Season Merino long-sleeve base layer top is just as comfy layered under your ski jacket as it is worn alone for summer backpacking.

Underwear TopsBase Layer Tops

Designed to be your go-to for warm or cold weather, the women's Smartwool Classic All-Season Merino quarter-zip top features lightweight, soft merino wool with a nylon core for increased durability.

Underwear TopsBase Layer Tops

Made from their lightest-weight jersey and built for comfort, the women's Smartwool Classic All-Season Merino quarter-zip base layer top is game for any adventure, any time of year.

Underwear TopsBase Layer Tops

Delivering exceptional performance and improved functionality, the women's Smartwool Classic Thermal Merino crew top maintains your warmth and active comfort as you hike, ski, bike and more.

Underwear TopsBase Layer Tops

Whatever high-intensity activity you get into, the women's Smartwool Classic Thermal Merino quarter-zip top delivers exceptional performance and improved functionality to keep you warm, dry and comfy.

Underwear TopsBase Layer Tops

Stay comfortable, dry and warm in the plus-size Smartwool Classic Thermal Merino quarter-zip top while enjoying your favorite activities year-round. An improved, active-minded fit is designed to move.

Underwear TopsBase Layer Tops

Made for all kinds of winter activities, the women's Craft Core Dry base-layer set has flatlock seams that enhance your comfort while the brushed jersey interior offers optimal warmth.

UnderwearBase Layer Sets

Built for any exercise in cold-weather conditions, the women's Craft Core Warm base-layer set uses flatlock seams to enhance your comfort while the brushed jersey inside offers optimal warmth.

UnderwearBase Layer Sets

Whether you layer it or wear it on its own, the Obermeyer Discover base layer crew top offers a flatseam construction for comfort, a soft brushed interior and fun one-of-a-kind colors and prints.

Underwear TopsBase Layer Tops

Whether you're carving through the snow or walking through town, the women's Obermeyer is an ultra-light base layer designed to move with your body, excelling in any conditions, on any mountain.

Underwear TopsBase Layer Tops

Thanks to its merino wool fabrication and flatlock construction, the Kari Traa Elenore women's long-sleeve base layer top feels cozy and comfy next to the skin, no matter the activity.

Underwear TopsBase Layer Tops

Look no further for that perfect base layer. The women's tasc Performance Elevation Merino T-shirt offers superior temperature regulation and moisture management without the bulk.

Underwear TopsBase Layer Tops

Let it snow! The women's Kari Traa Else Half-Zip base layer top blends soft merino wool and modern fabric mapping to keep you warm and comfortable on or off the slopes.

Underwear TopsBase Layer Tops