Men's Base Layers

Meet the better-than-ever Men's Classic Thermal Merino Base Layer Crew. We've updated this 100% Merino wool fan favorite with new colors and a new ...

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...

Technical. Comfortable. Reliable. That's what you get with our Men's Intraknit Merino Tech 1/4 Zip. This durable mid layer features our high-perfor...

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 midweight merino wool base layer top designed to help regulate temperature during high-intensity activity, the Merino 200 ZoneKnit™ Long Sleeve H...

The benchmark against which all others are judged, the Merino 200 Oasis Long Sleeve Crewe Cloud Dye features our most versatile merino wool jersey ...

A versatile, body-mapped zip-neck top that’s ideal for high-intensity adventures, the Merino 125 ZoneKnit™Long Sleeve Half Zip features our Cool-Li...

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...

Tackle cold temperatures with our Men's Long Sleeve Colorblock Henley! Perfectly crafted from Merino/polyester blend, this top moves sweat away ...

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...

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...

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 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...

A midweight merino base layer top designed to help regulate temperature during high-intensity activity, the 200 ZoneKnit™ Long Sleeve Crewe feature...

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