Men's Base Layers

An ultralight merino base layer top designed to help regulate body temperature during high-intensity activity, the 125 ZoneKnit™ Short Sleeve Crewe...

A breathable, lofted baselayer to keep you warm in cold conditions. Polartec® Power Grid® fabric with HeiQ® Pure odor control. Polartec® Power Gr...

A breathable, lofted baselayer to keep you warm in cold conditions. Polartec® Power Grid® fabric with HeiQ® Pure odor control. Made in a Fair Trade...

A classic, all-around 100% recycled polyester baselayer. The smooth, soft face makes for easy layering. Hollow-core yarns and a diamond-grid back t...

A classic, all-around 100% recycled polyester baselayer. The smooth, soft face makes for easy layering. Hollow-core yarns and a diamond-grid back t...

This ultra-soft knit turtleneck top for men offers a stylish look, all while providing protection against the cold. Completely versatile, our turtl...

Discover the perfect foundation for your layering system with SmartWool's  Intraknit™ collection. This Men's Intraknit Thermal Merino Base Layer...

Midweight merino base layer bottoms designed to help regulate temperature during high-intensity activity, the 200 ZoneKnit™ Leggings feature 100% p...

Ultralight merino base layer bottoms designed to help regulate body temperature during high-intensity activity, the 125 ZoneKnit™ Leggings feature ...

Our best-selling base layer bottoms made from soft and breathable 100% merino wool jersey, the 200 Oasis Leggings With Fly are the perfect foundati...

Technical, cold-weather base layer bottoms for highly aerobic days, the 260 Zone Leggings feature zoned ventilation panels for active temperature r...

Midweight base layer bottoms perfect for skiing, winter hiking, or cold-weather layering, the 260 Tech Leggings With Fly are a warmer version of ou...

Experience the revolutionary Intraknit™ line with the Men's Intraknit™ Thermal Merino Base Layer 1/4 Zip. This Smartwool® base layer is designed...

Our Men's Intraknit™ Thermal Merino Base Layer Crew is anything but ordinary. Super lightweight, ultra-moveable and designed to maximize thermor...

Our Men's Classic Thermal Merino Base Layer 1/4 Zip has an improved fit that takes functionality to the next level. Crafted with 100% responsibl...

Experience superior fit and performance with Men's Intraknit™ Thermal Merino Base Layer Colorblock Crew! Crafted with our innovative Intraknit™ tec...

Our Men's Classic Thermal Merino Base Layer Bottom just got an upgrade; now it fits better, and its technical performance promises you'll be abl...

An ultralight merino base layer top designed to help regulate body temperature during high-intensity activity, the 125 ZoneKnit™ Long Sleeve Crewe ...

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

A heavyweight merino wool base layer for highly aerobic days in cold weather, the 260 Zone Long Sleeve Half Zip features zoned ventilation panels f...

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% merin...

Our versatile 100% merino wool base layer top with a classic zip-neck design, the 200 Oasis Long Sleeve Half Zip combines casual comfort with techn...