The most trusted
base
layers
since 1999.

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  • Classic
    Thermal
  • Classic
    All-Season
  • Intraknit ™
    Thermal
  • Intraknit ™
    Active
Most Popular
Our fan-favorite base made from 100% ZQ Merino wool.

ClassicThermal

Made for cool to cold weather outdoor activities
  • Slim Fit + Plus Size
  • Midweight: 250g/m
  • Versatile use for colder seasons
Body Temp
Regulation
Moister
Management
Odor
Resistant
ZQ Wool
Certified
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Most Versatile
Our year-round base made with a Merino blend to maximize durability.

ClassicAll-Season

Warm to cool weather activities
  • Slim fit
  • Lightweight: 150g/m
  • Worn alone on warm days. A layering foundation on cooler days.
Body Temp
Regulation
Moister
Management
Odor
Resistant
ZQ Wool
Certified
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Highest-Performing
Our most advanced performance base is 3D-knit to maximize articulation and ventilation.

Intraknit ™ Thermal

High-energy activities in cool to cold weather.
  • Slim fit
  • Midweight
  • Designed for warmth and an enhanced performance
Body Temp
Regulation
Moister
Management
Odor
Resistant
ZQ Wool
Certified
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Plays hard. Stays cool.
Our newest 3D-knit base designed to help keep you cool.

Intraknit ™ Active

Year-round high-aerobic activities
  • Slim Fit
  • Midweight
  • Features the natural cooling properties of TENCEL ™ fibers
Body Temp
Regulation
Moister
Management
Odor
Resistant
ZQ Wool
Certified
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Made to help you stay comfortable, confident,
and outside longer doing what you love.

Responsibly Sourced WoolWe only put our softest, ZQ-certified Merino wool next to your skin.
Wide-Ranging CollectionWe offer comfort for every adventurer, season, and activity—with women’s plus sizes in our classic base layer styles.
Knit ExpertiseOur 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.
Men's Base Layers Women's Base Layers Women's Plus Size Base Layers
Men's Base Layer Women's Base Layer Women's Plus Size Base Layer

go far. feel good.™


We think you’ll love our award-winning base layers, but don’t just take it from us. Hear it from the Smartwool community.

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 women’s Smartwool® base layers, men’s Smartwool® base layers, and the entire Smartwool® Intraknit™ base layer collection today and explore forever.

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