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Lightweight Base Layer Bottoms

(41 products)
Products (41)
Sort: Best Match
    REI Co-opMerino 185 Base Layer Bottoms - Men's
    $79.95
    169 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    Top Rated
    REI Co-opLightweight Base Layer Tights - Women's
    $44.95
    11 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus, Petite
    Top Rated
    REI Co-opLightweight Base Layer Bottoms - Men's
    $44.95
    28 reviews with an average rating of 4.6 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big, Tall
    tasc PerformanceElevation Merino Base Layer Bottoms - Men's
    $46.73 - $54.73
    Save 30% - 40%
    compared to  $79.00
    44 reviews with an average rating of 3.9 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Big, Regular
    REI OUTLET
    Arc'teryxRho LT Base Layer Bottoms - Men's
    $59.83 - $100.00
    61 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    SmartwoolClassic All-Season Merino Base Layer Bottoms - Men's
    $100.00
    30 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    REI Co-opMerino 185 Base Layer Bottoms - Women's
    $79.95
    122 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    SmartwoolClassic All-Season Merino Base Layer Bottoms - Women's
    $68.83 - $100.00
    25 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    REI Co-opMerino 185 Base Layer Bottoms - Women's Plus Sizes
    $39.83
    Save 50%
    compared to  $79.95
    11 reviews with an average rating of 3.9 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Plus
    Arc'teryxRho Base Layer Bottoms - Women's
    $59.83 - $100.00
    38 reviews with an average rating of 4.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    Kari TraaKlara High-Waisted Base Layer Pants - Women's
    $62.73 - $66.73
    Save 25% - 30%
    compared to  $90.00
    14 reviews with an average rating of 3.9 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    REI OUTLET
    tasc PerformanceElevation Merino Base Layer Bottoms - Women's
    $46.73
    Save 40%
    compared to  $79.00
    67 reviews with an average rating of 4.1 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    REI OUTLET
    Free CountryForce Grid Fleece Base Layer Bottoms - Women's
    $26.73
    Save 51%
    compared to  $55.00
    11 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    REI OUTLET
    SmartwoolIntraknit Thermal Merino Base Layer Bottoms - Men's
    $150.00
    33 reviews with an average rating of 4.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    Arc'teryxSatoro Merino Wool Base Layer Bottoms - Women's
    $95.73
    Save 20%
    compared to  $120.00
    0 reviews
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    REI OUTLET
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    HalfdaysSophia Base Layer Leggings - Women's
    $46.83 - $95.00
    123 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    REI Co-opMerino 185 Base Layer Bottoms - Men's Tall Sizes
    $79.95
    17 reviews with an average rating of 3.9 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Tall, Big
    SmartwoolClassic All-Season Merino 3/4 Base Layer Bottoms - Men's
    $85.00
    5 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    Kari TraaFryd Base Layer Pants - Women's
    $40.73
    Save 25% - 32%
    compared to  $55.00 - $60.00
    18 reviews with an average rating of 3.4 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Plus
    REI OUTLET
    Kari TraaLucie Base Layer Pants - Women's
    $58.73
    Save 26%
    compared to  $80.00
    6 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    REI OUTLET
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    Terms apply
    SmartwoolIntraknit Thermal Merino Base Layer Bottoms - Women's
    $150.00
    30 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    Kari TraaSval Base Layer Pants - Women's
    $49.73
    Save 28%
    compared to  $70.00
    2 reviews with an average rating of 3.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    REI OUTLET
    Ortovox120 Comp Light Short Base Layer Pants - Men's
    $70.00
    3 reviews with an average rating of 5.0 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular, Big
    Top Rated
    Kari TraaRose High-Waisted Base Layer Pants - Women's
    $120.00
    14 reviews with an average rating of 4.5 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    SmartwoolIntraknit Thermal Merino Base Layer Bottoms - Women's
    $92.73
    Save 28%
    compared to  $130.00
    30 reviews with an average rating of 4.2 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    REI OUTLET
    New arrival
    Black DiamondCoefficient LT One Piece Base Layer - Men's
    $149.73
    Save 31%
    compared to  $219.00
    10 reviews with an average rating of 3.3 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    REI OUTLET
    Kari TraaAlma Base Layer Pants - Women's
    $90.00
    0 reviews
    Underwear Weight:
    Ultralightweight
    Size Type:
    Regular
    Kari TraaAlma Pants - Women's
    $68.73
    Save 23%
    compared to  $90.00
    0 reviews
    Underwear Weight:
    Ultralightweight
    Size Type:
    Regular
    REI OUTLET
    RHONEApres Houndstooth Seamless Base Layer Leggings - Women's
    $88.93
    Save 30%
    compared to  $128.00
    3 reviews with an average rating of 4.3 out of 5 stars
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    Kari TraaFierce Base Layer Pants - Women's
    $46.73
    Save 29%
    compared to  $66.00
    0 reviews
    Underwear Weight:
    Lightweight
    Size Type:
    Regular
    REI OUTLET
Sort: Best Match