No categories available
No brands available

When it comes to base layers, basic is better. The men's Lole Logan base layer bottoms are perfect under your gear for outdoor training or activities, or for everyday life.

Layered under a pair of pants or on their own, these women's Smartwool Merino 150 Lace base layer bottoms are just the thing for an afternoon of snowshoeing or cool-weather hiking.

Soft, breathable and naturally odor resistant, the ultrafine merino wool of the men's REI Co-op Merino 185 base layer bottoms is just as beloved while sweating on the trail as sleeping in the tent.

Soft, breathable and naturally odor resistant, the ultrafine merino wool of the men's REI Co-op Merino 185 base layer bottoms is beloved for sweating on the trail—and just sleeping!

Just as beloved while sweating on the trail as sleeping in the tent, the ultrafine merino wool of the women's REI Co-op Merino 185 base layer bottoms is soft, breathable and naturally odor resistant.

Just as beloved while sweating as while sleeping, the ultrafine merino wool of the women's REI Co-op Merino 185 base layer bottoms is soft, breathable and naturally odor resistant.

Warm merino bottoms for the coldest months, the women's Icebreaker Merino 260 Tech High Rise base layer leggings are great for winter layering on skiing, snowshoeing or other cold-weather adventures.

Ideal for cold weather, the kids' REI Co-op merino midweight base layer bottoms are soft—not scratchy—naturally regulate temp and made with wool that's certified to the Responsible Wool Standard.

Keep the winter chill away with the women's Icebreaker MerinoFine base layer leggings, which feature a high waist for added coverage—and its merino wool is naturally stretchy and odor resistant.

An ideal performance layer, the men's REI Co-op Midweight Base Layer Bottoms boast a smooth face and low-bulk seams for easy layering and a brushed back for added warmth and comfort.

Stay dry, warm and stoked all day with the men's Burton Midweight Base Layer pants, which give you moisture-wicking fabric with a cottonlike feel and a plush waistband.

Start with a high-performing next-to-skin layer and take advantage of the snow. The women's REI Co-op Midweight Base Layer Tights have a smooth face for easy layering and brushed interior for warmth.

The kids' REI Co-op Midweight Long Underwear Bottoms are warm and very good at wicking moisture, making them an ideal base layer for highly aerobic cold-weather fun, like skiing and snowshoeing.

The toddlers' REI Co-op Midweight Long Underwear Bottoms are warm and very good at wicking moisture, making them an ideal base layer for highly aerobic cold-weather fun, like skiing and snowshoeing.