Best Merino Wool Base Layers | Smartwool®
Explore the Base Layer Collections
Our year-round base made with a Merino blend to maximize durability.
ClassicAll-Season
- Slim fit
- Lightweight: 150g/m
- Worn alone on warm days. A layering foundation on cooler days.
REGULATION
MANAGEMENT
RESISTANT
CERTIFIED
Our fan-favorite base made from 100% ZQ Merino wool.
ClassicThermal
- Slim Fit + Plus Size
- Midweight: 250g/m
- Versatile use for colder seasons
REGULATION
MANAGEMENT
RESISTANT
CERTIFIED
Our most advanced performance base is 3D-knit to maximize articulation and ventilation.
Intraknit™Thermal
- Slim fit
- Midweight
- Designed for warmth and an enhanced performance
REGULATION
MANAGEMENT
RESISTANT
CERTIFIED
Our newest 3D-knit base designed to help keep you cool.
Intraknit™Active
- Slim Fit
- Midweight
- Features the natural cooling properties of TENCEL™ fibers
REGULATION
MANAGEMENT
RESISTANT
CERTIFIED
Made to help you stay comfortable, confident,
and outside longer doing what you love.
Responsibly Sourced Wool
We only put our softest, ZQ-certified Merino wool next to your skin.
Wide-Ranging Collection
We offer comfort for every adventurer, season, and activity—with women’s plus sizes in our classic base layer styles.
Knit Expertise
Our apparel technologies offer a high degree of comfort, perfect fit, and durability.
go far. feel good.™ Guarantee
If within two years, you don’t love your base layer, we’ll make it right.
Endless comfort starts here.
No matter how you get outside, it’s easy to find your best Merino wool base layer with Smartwool. Whether you need a lightweight Merino wool base layer for year-round adventures or our warmest Smartwool® base layer for every winter outing, we have the comfort you need to go farther. Shop Smartwool® women’s base layers, men’s base layers, kid’s base layers and the entire Smartwool® Intraknit™ base layer collection today and explore forever.