Icebreaker's versatile, go-anywhere shirt made from breathable 100% merino wool jersey, the 200 Oasis Long Sleeve Crewe is the best-selling base layer top.

Comfortable, considered and eco-friendly, celebrate the future of sustainable sportswear with ODLO’s Women’s ACTIVE WARM ECO Long-Sleeve base layer top.

Crafted from recycled polyester fibres to reduce its carbon footprint, this next generation base layer is ideal for alpine pursuits thanks to its warm and breathable qualities. 

Meet the new and improved Women's Merino 250 Base Layer Crew.

Smartwool have updated this 100% Merino wool fan-favorite with an enhanced fit to improve functionality while elevating aesthetics. The addition of shoulder panels its flatlock seam construction helps prevent chafing and increases your comfort level.

Add one of Smartwool's best base layers for cold weather to your winter wardrobe and experience the difference the next time you go skiing, hiking, climbing, or biking.

An all-season favorite, the 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 Core Spun technology—which features Merino wrapped around a nylon core for added durability while still keeping the comfort of ultra-soft, responsibly sourced Merino next to skin.

Smartwool's Raglan sleeves eliminate shoulder seams for perfect comfort under a pack, and smooth merrow stitching wraps from side to front to keep you looking as good as you feel.

Warm, dry and sustainable – welcome to the future of sportswear with ODLO’s Women’s ACTIVE WARM ECO Half-Zip Turtleneck base layer top.

Crafted from 100 percent recycled materials, this versatile base layer brings an environmental ethos to the core of your sportswear.

The enhanced thermoregulation and exceptional comfort delivered by the ACTIVE X-WARM ECO Long-Sleeve base layer top make this versatile garment a winter-weather essential for active women.

Using soft insulation pads to protect particularly sensitive areas of the body from the cold, the ACTIVE X-WARM range provides excellent insulation as the cold sets in, while excellent moisture management properties guarantee you stay warm and dry at all times. 

We've updated the fit of our Women's Classic Thermal Merino Base Layer 1/4 Zip to improve functionality while also enhancing aesthetics. As one of our heaviest base layer tops and best base layers for cold weather, this garment uses 100% responsibly sourced Merino wool, shoulder panels, and a flatlock seam construction to help minimize chafing as well as help keep you comfortable and temperature-regulated as you enjoy high-intensity skiing, hiking, running, and more.

A warmer, midweight version of our best-selling Oasis, the 260 Tech Long Sleeve Half Zip is a go-to piece for winter layering, made with 100% merino wool.

Meet the new and improved Women's Classic Thermal Merino Base Layer Crew. We've updated this 100% Merino wool fan favorite with new color options and an enhanced fit to improve functionality while elevating aesthetics. The addition of shoulder panels and its flatlock seam construction help prevent chafing and increase your comfort level. Add one of our best base layers for cold weather to your winter wardrobe and experience the difference the next time you go skiing, hiking, climbing, or biking.

Icebreaker's versatile, go-anywhere shirt made from breathable 100% merino wool jersey, the 200 Oasis Long Sleeve Crewe is the best-selling base layer top.

An incredibly warm merino wool base layer with a unique jacquard pattern, the Merino 260 Vertex Long Sleeve Crewe On-Piste is a go-to piece for winter layering—ideal for skiing, snowshoeing and other cold-weather pursuits. The simple line pattern references the delicate curves of ski track arcing down the mountain.

Icebreaker's versatile, go-anywhere shirt made from breathable 100% merino wool jersey, the 200 Oasis Long Sleeve Crewe is the best-selling base layer top.