Men's Baselayers

Smartwool has updated the fit of the Men's Merino 250 Base Layer 1/4 Zip to improve functionality while also enhancing aesthetics.

Smartwool has updated the Men's Merino 250 Base Layer Bottom to bring you a better fitting, more functional tight.

This minimalist-style crew is anything but insignificant.

Performance first layer for trail runs and fast-paced pursuits in cooler weather.

Meet the better-than-ever Men's Merino 250 Base Layer Crew.

Perfect for brisk walks, cold hikes, or enjoying the comfort of working from home, theBest-selling and buttery-soft, the Baritone Collection is ultra comfortable when you're lounging, and beefed up with ActiveTemp™ when you're moving. Its soft, brushed in

Breathable, moisture-wicking, insulated jersey with collar zip to aid with temperature regulation

The athletic fit of the Men’s Merino Sport Ultralite Long Sleeve complements the movements of your body.

Days when the air is crisp and the frost might bite, but Mother Nature continues to call. Embrace the outdoors while keeping your body toasty in this super-soft, midweight baselayer tee.

Days when the air is crisp and the frost might bite, but Mother Nature continues to call. Designed using a recycled polyester and merino wool blend, this mid-weight thermoregulating base layer lives and breathe for the great outdoors.

Days when the air is crisp and the frost might bite, but Mother Nature continues to call. Embrace the outdoors while keeping your body toasty in this super-soft, midweight baselayer 1/2 zip top.

The Men's Merino 250 Base Layer Colorblock Crew features 100% responsibly sourced Merino wool made with an interlock knit for enhanced comfort, breathability, thermoregulation, and odor resistance.

Spring skiing or summer camping? The year-round Merino 150 Base Layer Long Sleeve is game for either.

A year-round favorite, our Merino 150 Base Layer Bottoms work hard to keep you comfortable everywhere, from the ski lifts to the campsite.

Performance first layer bottom for trail runs and fast-paced pursuits in cooler weather.

Performance first layer for trail runs and fast-paced pursuits in cooler weather.

A classic, go-anywhere all-around baselayer, made with 100% recycled content. The smooth, soft face makes for easy layering; hollow-core yarns and a diamond-grid back trap warm air, wick moisture and dry fast. HeiQ® Fresh durable odor control keeps things

The most versatile polyester baselayer with the greatest comfort range and Polygiene® permanent odor control.