Men's Base Layer Bottoms

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...

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...

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 ...

Performance base layer for lower output activities in cool to cold temperatures. The Rho LT is your lightweight thermal base layer for low and medi...

Performance base layer for lower output activities in cool to cold temperatures. The Rho LT is your lightweight thermal base layer for low and medi...

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...

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

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...