Skip to search results
loaded 370 results
Long Underwear
(370 products)Products (370)
Sort: Best Match
- IcebreakerMerino 260 Tech Long-Sleeve Half-Zip Thermal Base Layer Top - Women'sTop Rated$99.73Save 26%compared to  $135.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- Arms of Andes300 Lightweight Alpaca Wool Half-Zip Base Layer Top - Men's$135.00
- SmartwoolIntraknit Thermal Merino Crew Base Layer Top - Men's$130.00
- KUHLReactiv Lite Grid Long-Sleeve Crew Base Layer Top - Women'sNew arrival$109.00
- CraftCORE Dry Active Comfort Base Layer Top - Women's$39.73Save 38%compared to  $64.95Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- REI Co-opMidweight Crew Base Layer Top - Toddlers'Top Rated$24.95
- Icebreaker125 ZoneKnit Long-Sleeve Crewe Base Layer Thermal Top - Women's$93.73Save 25%compared to  $125.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- ArtilectDarkhorse 185 Zoned Crew Base Layer Top - Men'sTop Rated$109.73Save 31%compared to  $160.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- ArtilectFlatiron 185 Crew Base Layer Top - Men's$96.73 - $109.73Save 30% - 31%compared to  $140.00 - $160.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- Ortovox120 Comp Light Base Layer Hoody - Men's$120.00
- Ortovox230 Competition Zip-Neck Base Layer Top - Men's$120.00
- Sweaty BettyHigh-Neck Jacquard Base Layer Top - Women'sTop Rated$82.73Save 29%compared to  $118.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- ArtilectGoldhill 125 Zoned Crew Base Layer Top - Men's$79.73Save 38%compared to  $130.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- Ortovox185 Rock'n'wool Long Base Layer Pants - Men's$110.00
- PatagoniaCapilene Thermal Weight Zip-Neck Top - Men's$109.00
- SpraywayEffra Crew Base Layer Top - Women's$36.73Save 26%compared to  $49.95Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- HalfdaysJohnson Base Layer Top - Women's$49.83Save 41%compared to  $85.00
- Terramar2.0 Cloud Nine Midweight Performance Thermal Turtleneck - Women's$32.73Save 31%compared to  $48.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- Kari TraaSmekker Long-Sleeve Base Layer Top - Women's$89.73Save 25%compared to  $120.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- Helly HansenHH Durawool Crew Long-Sleeve Base Layer - Women's$90.00
- Helly HansenLIFA ACTIVE Graphic Crew Base Layer Top - Women's$46.73Save 28%compared to  $65.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- Picture Organic ClothingNangha Base Layer Top - Men's$44.83Save 50%compared to  $90.00
- IcebreakerMerino 260 Vertex Long-Sleeve Crewe Thermal Base Layer Top - Women's$99.73Save 28%compared to  $140.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- Icebreaker200 ZoneKnit Long-Sleeve Crewe Base Layer Thermal Top - Men'sTop Rated$109.73Save 26%compared to  $150.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- SmartwoolClassic All Season Merino Long-Sleeve Base Layer Top - Men'sTop Rated$66.73Save 25%compared to  $90.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- Free CountryForce Grid Fleece Base Layer Top - Men's$29.73Save 33%compared to  $45.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- SpraywayEffra Hoody Base Layer Top - Women's$49.73Save 28%compared to  $69.95Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- SpraywayEffra Jacket Base Layer Top - Women's$46.73Save 28%compared to  $64.95Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- CotopaxiLiso Base Layer Top - Men'sTop Rated$44.73Save 31%compared to  $65.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
- Arc'teryxRho Base Layer Hoody - Women'sTop Rated$96.73Save 19%compared to  $120.00Members use code OUT4JUL25 for $20 off $100+ at REI OutletREI OUTLET
151–180 of 370 products
Sort: Best Match