Base Layer & Thermal Underwear

Under Armour UA Base™ 2.0 Women's Leggings

$60.00

Meet the all-new UA Base™—delivering the same trusted warmth without the bulk—now softer and smoother than ever for unmatched comfort on every adventure. UA Base™ 2.0 Active Baselayer is lightweig...

$60.00

Meet the all-new UA Base™—delivering the same trusted warmth without the bulk—now softer and smoother than ever for unmatched comfort on every adventure. UA Base™ 2.0 Active Baselayer is lightweig...

Woman wearing a black long-sleeve top with a zipper on a light pink background

$140.00

~~$0.00~~

Warm, versatile Polartec® Power Stretch® Pro base layer for cold conditions. The Kyanite Baselayer Zip Neck was previously the Rho Heavyweight Zip Neck. The Kyanite Baselayers are made for cold day...

25% Off

Person wearing a black long-sleeve top and blue pants with a beige cap on a light gray background

Person wearing a black hoodie and gray pants on a light gray background

$48.75

~~$65.00~~

The super soft UPF 50 hoody for adventures big and small Perfect for giving it your all on the next pitch or pacing on your favorite trail, the Butter™ Long Sleeve Hoody is big on performance witho...

25% Off

Person wearing a black long-sleeve top and red beanie on a light gray background

Woman wearing a light purple long-sleeve athletic top on a white background

$52.50

~~$70.00~~

The super soft, half-zip that’s at home in the high alpine and casual days at lower elevations This perfect moisture-wicking base layer is buttery soft, allowing you to move effortlessly through an...

25% Off

Person wearing black long-sleeve top and leggings with gray socks on a white background

$60.00

~~$80.00~~

An alpine-inspired tight that can be worn as a single or base layer From high alpine trails to the climbing gym, the Butter™ Tight is a versatile, buttery soft base layer that pairs perfectly under...

25% Off

Person wearing a black long-sleeve top and maroon puffer pants with a purple beanie on a light gray background

Person wearing a purple long-sleeve shirt and green pants on a light gray background

$45.00

~~$60.00~~

Crucial UPF 50 sun protection that’s moisture wicking and anti-odor for running solo or layering. Make every high effort outing smooth as butter with a long-sleeve layer that’s worth its weight in ...

Woman wearing a blue and floral long-sleeve top on a white background

Woman wearing a patterned long-sleeve top and leggings on a white background

$130.00

Meet the Women's Classic Thermal Merino Base Layer Colorblock Crew. This 100% Merino wool fan-favorite combines the moisture management, temperature regulation, and odor resistance of Merino with t...

Woman wearing a dark brown long-sleeve top and black leggings on a light gray background

Woman wearing a dark long-sleeve top and leggings on a light gray background

$140.00

Meet the Women's Classic Thermal Merino Mock Neck. This 100% Merino wool fan-favorite combines the moisture management, temperature regulation, and odor resistance of Merino with the comfort of an ...

Woman wearing a black long-sleeve athletic shirt on a white background

Person wearing a black full-body suit on a white background

$90.00

An all-season favorite, the Women's Classic All-Season Merino Base Layer Long Sleeve can be sported as a base layer in the fall or summer when it's time to go backpacking. This base layer features ...

25% Off

Coldpruf Quest Performance Women's Crew Shirt

$29.99

~~$40.00~~

The Holy Grail of base layers. Single-layer, jersey knit fabric Fabric Weight: 6.5 oz Fiber Content: 85% ColdPruf® Technical Fiber Polyester with SILVADUR™ Intelligent Freshness / 15% Spandex...

$179.00

VOORMI does it again with their Women's Expedition 1/4 Zip top! The 1/4 Zip boasts our innovative DUAL SURFACE™ Precision Blended Wool, a fabric that keeps your warm without compromising breathabil...

Person wearing a navy and red sweater with black pants on a white background

Person wearing a navy and red sweater with dark pants on a white background

$175.00

Meet the Women's Alpine Crew—a premium 100% Merino wool base layer built for high-output performance in cold weather. Merino’s natural abilities to regulate temperature, wick moisture, and resist o...

$43.00

~~$0.00~~

The Women's Active Stretch Crewneck is a versatile long-sleeve base layer designed to keep you comfortable and dry during any activity. Its moisture-wicking fabric moves with you, providing a snug ...

$43.00

~~$0.00~~

The Womens Active Stretch Tight combines moisture-wicking technology with thermal warmth to keep you comfortable and dry. Its stretchy, close-fitting fabric moves with your body, providing support ...

Person wearing black leggings on a white background

Person wearing black long-sleeve top and leggings on a white background

$90.00

Our Women's Classic All-Season Merino Base Layer Bottoms are the perfect layer to put on for your warm-weather adventures. Made of lightweight, breathable Merino, these base layer pants have an upd...

$37.99

~~$0.00~~

Performance that moves with you. The ColdPruf® Style 49A Performance Crew is built for cold to very cold weather and medium- to high-activity levels. Its athletic, close-to-body fit makes it an exc...

$37.99

~~$0.00~~

Performance that moves with you. The ColdPruf® Style 49B Performance Pants are designed for cold to very cold weather and medium- to high-activity levels. With a close athletic fit, they sit just b...