Home Smartwool Kid's Classic Thermal Merino Base Layer Bottoms for Boys and Girls(Toddler/Little Kid/Big Kid)

Smartwool Kid's Classic Thermal Merino Base Layer Bottoms for Boys and Girls(Toddler/Little Kid/Big Kid)

Regular price $65.00 Sale price $19.50
70% OFF
Size: XX-Small

Size
Color: Deep Navy Geo Peaks

Color

size

Outdoor Sock & Apparel Size Guide

Use the charts below to find the right fit for socks, tops, bottoms, headwear and gloves. Measurements are shown in both inches and centimetres. Tip: if you fall between two sizes, most merino wool apparel is designed to layer — choose the larger size for a relaxed fit and the smaller size for a performance fit.

Unisex Socks Men's Apparel Women's Apparel Kids' Socks Headwear & Gloves

1. Sock Size (Unisex)

Sizing is based on U.S. shoe size and EU equivalent.
Size U.S. Men's U.S. Women's EU UK
S 3 – 5.5 4 – 6.5 34 – 38 2 – 4.5
M 6 – 8.5 7 – 9.5 39 – 42 5.5 – 8
L 9 – 11.5 10 – 12.5 43 – 46 9 – 11.5
XL 12 – 14.5 — 47 – 50 12.5 – 14
Sock sizing is based on foot length. If you wear a half size, size up for a more relaxed fit or down for a snug performance fit.

2. Men's Tops & Base Layers

Body measurements. Measure over light clothing.
Size Chest (in) Chest (cm) Waist (in) Waist (cm) Sleeve (in) Sleeve (cm) Hip (in) Hip (cm)
XS 33 – 35 84 – 89 27 – 29 69 – 74 31 – 32 79 – 81 33 – 35 84 – 89
S 36 – 38 91 – 97 29 – 31 74 – 79 32 – 33 81 – 84 36 – 38 91 – 97
M 39 – 41 99 – 104 32 – 34 81 – 86 33 – 34 84 – 86 39 – 41 99 – 104
L 42 – 44 107 – 112 36 – 38 91 – 97 34 – 35 86 – 89 42 – 44 107 – 112
XL 46 – 48 117 – 122 40 – 42 102 – 107 35 – 36 89 – 91 46 – 48 117 – 122
XXL 50 – 52 127 – 132 44 – 46 112 – 117 36 – 37 91 – 94 50 – 52 127 – 132
Chest: measure under the arms, across the fullest part. Sleeve: from the centre back of the neck, over the shoulder, to the wrist.

3. Women's Tops & Base Layers

Body measurements over light clothing.
Size Numeric Bust (in) Bust (cm) Waist (in) Waist (cm) Hip (in) Hip (cm) Sleeve (in) Sleeve (cm)
XS 0–2 30 – 32 76 – 81 24 – 26 61 – 66 33 – 35 84 – 89 29 – 30 74 – 76
S 4–6 32 – 34 81 – 86 26 – 28 66 – 71 35 – 37 89 – 94 30 – 31 76 – 79
M 8–10 34 – 36 86 – 91 28 – 30 71 – 76 37 – 39 94 – 99 31 – 32 79 – 81
L 12–14 37 – 39 94 – 99 31 – 33 79 – 84 40 – 42 102 – 107 32 – 33 81 – 84
XL 16 41 – 43 104 – 109 34 – 36 86 – 91 44 – 46 112 – 117 33 – 34 84 – 86
Bust: measure at the fullest part, keeping the tape level. Waist: measure at the narrowest point, just above the navel.

4. Men's Bottoms

Pants, leggings, tights & shorts.
Size Waist (in) Waist (cm) Hip (in) Hip (cm) Inseam – Short (in) Inseam – Regular (in) Inseam – Long (in)
XS 27 – 29 69 – 74 33 – 35 84 – 89 29 31 33
S 29 – 31 74 – 79 35 – 37 89 – 94 29 31 33
M 32 – 34 81 – 86 38 – 40 97 – 102 30 32 34
L 36 – 38 91 – 97 42 – 44 107 – 112 30 32 34
XL 40 – 42 102 – 107 46 – 48 117 – 122 30 32 34
XXL 44 – 46 112 – 117 50 – 52 127 – 132 30 32 34
Inseam is the inside-leg length. For bottoms sold as Short / Regular / Long, pick the inseam length that matches your height.

5. Women's Bottoms

Pants, tights, leggings & shorts.
Size Numeric Waist (in) Waist (cm) Hip (in) Hip (cm) Inseam – Short (in) Inseam – Regular (in) Inseam – Long (in)
XS 0 – 2 24 – 26 61 – 66 33 – 35 84 – 89 28 30 32
S 4 – 6 26 – 28 66 – 71 35 – 37 89 – 94 28 30 32
M 8 – 10 28 – 30 71 – 76 37 – 39 94 – 99 28 30 32
L 12 – 14 31 – 33 79 – 84 40 – 42 102 – 107 28 30 32
XL 16 34 – 36 86 – 91 44 – 46 112 – 117 28 30 32

6. Hats & Headwear

Beanies, neck gaiters & caps.
Size Head Circumference (in) Head Circumference (cm)
OSFM 21 – 23.5 54 – 60
S / M 21 – 22.5 54 – 57
L / XL 22.5 – 24 57 – 61
Measure around the forehead, just above the ears and across the widest part at the back of the head.

7. Gloves & Mittens

Unisex sizing. Measure around the palm.
Size Palm Circumference (in) Palm Circumference (cm) Hand Length (in) Hand Length (cm)
XS 6 – 6.5 15 – 16 6.5 – 7 16.5 – 18
S 7 – 7.5 18 – 19 7 – 7.5 18 – 19
M 8 – 8.5 20 – 21 7.5 – 8 19 – 20
L 9 – 9.5 23 – 24 8 – 8.5 20 – 21.5
XL 10 – 10.5 25 – 27 8.5 – 9 21.5 – 23
Palm circumference: measure around the knuckles of a relaxed hand, excluding the thumb. Hand length: from the base of the palm to the tip of the middle finger.

8. Kids' Socks

Sized by age range and shoe size.
Size Age Range U.S. Kids' Shoe EU Shoe UK Shoe
S 4 – 7 yrs 11 – 13 28 – 32 10 – 12
M 7 – 10 yrs 13 – 3Y 32 – 34 12 – 2Y
L 10 – 14 yrs 3Y – 6Y 35 – 38 2Y – 5Y
Toddler (under 4 yrs) styles are sized as XS — please refer to the specific product page for that chart.

How to Measure

Three quick steps for an accurate fit.

1. Use a Soft Tape

Use a flexible fabric tape measure. Keep it level and snug against the body, without pulling tight.

2. Measure Over Light Layers

For body measurements, wear light clothing. Measure chest or bust at the fullest part, waist at the natural waistline.

3. Pick by Fit Preference

Between two sizes? Choose the larger size for a relaxed fit and the smaller size for a close-to-skin, performance fit.

All measurements are approximate. Fit may vary slightly by style. If you need further help, please contact our support team.

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Smartwool Kid's Classic Thermal Merino Base Layer Bottoms for Boys and Girls(Toddler/Little Kid/Big Kid)

Smartwool Kid's Classic Thermal Merino Base Layer Bottoms for Boys and Girls(Toddler/Little Kid/Big Kid)

Our Kids' Classic Thermal Merino Base Layer Bottom uses our super soft Mid 250 interlock knit—perfect for layering in cool conditions and great for wearing alone on a mild day. Now your kids can be as warm, dry and comfortable as you are. In your Smartwool® base layers.

  • 100% Merino Wool
  • Imported
  • ABOUT THIS PRODUCT: Keep kids warm and comfy with our Kids' Classic Thermal Merino Base Layer Bottom. Made with ultra-soft interlocking knit, it’s perfect for layering in cold weather or wearing solo on mild days. This breathable, moisture-wicking Merino wool base layer helps kids stay dry and cozy—just like your favorite Smartwool layers.
  • FEATURES: Designed to follow the body’s contours, this base layer features an interlock knit Merino wool fabric for breathability, comfort, and thermoregulation. A Merino-lined elastic waistband offers a soft next-to-skin feel, while flatlock seams help reduce chafing and enhance comfort through every move.
  • CARE INSTRUCTIONS: Machine wash warm on a gentle cycle with like colors to preserve color consistency and ensure long-lasting wear.
  • GO FAR, FEEL GOOD – SMARTWOOL EST. 1994: Born on the slopes of Colorado, Smartwool is driven by the belief that time outside is time well spent. We harness the natural performance of Merino wool to keep you comfortable, so you can go farther, feel better, and experience more—every step of the way.
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