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Named Best Overall Base Layers for Women by GearJunkie (2025-2026). Meet the new and improved Women's Classic Thermal Merino Base Layer Crew....
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Temp Rating:
Classic Thermal
Warm
50° +
Cool
25° - 50°
Cold
<25°
Base Layer
Classic Thermal Merino
Made with 100% Merino wool for natural sweat management, odor-resistance, and temperature regulation.
Compare Base Layer Styles
Smartwool Base Layers
Responsibly sourced, naturally performing Merino wool—helping you stay dry from sweat, resistant to odors, and comfortable at the right body temperature 365 days a year.
Classic All-Season Merino
Our most versatile year-round fabric features a nylon core for durability, while keeping soft 100% Merino wool next to skin.
Classic Thermal Merino
This Base Layer
Made with 100% Merino wool for natural sweat management, odor-resistance, and temperature regulation.
Intraknit™ All-Season Merino
Our 3D-knit base layer features a fabric that combines natural benefits of Merino wool with softness and cooling properties of TENCEL™.
Intraknit™ Thermal Max Merino
Our Intraknit™ technology is helping revolutionize the base layer industry. Including 3D-mapping for a custom fit, durability, and freedom to move.
Intraknit™ Thermal Merino
Our most advanced performance base layer is 3D-knit to provide a tailored fit with mesh ventilation to balance warmth and breathability.
Features
Our slim fit is intended to follow the contours of the body
Fabric helps combine the moisture management, temperature regulation, and odor resistance of 100% Merino wool with interlock knit for comfort
Back body seam wraps to front
Raglan sleeves
Flatlock seam construction designed to help increase comfort and minimize chafing
Made in Vietnam: 100% Merino Wool. Exclusive of Decoration.
SW016369
Care
Machine Wash Warm Gentle Cycle
Wash With Like Colors
Do Not Bleach
Tumble Dry Low
Cool Iron As Needed
Do Not Iron Decoration
Do Not Dry Clean
Women's Classic Thermal Merino Base Layer Crew
$125.00
The Breakdown
Comfortable in the uncomfortable.
Classic Thermal
Our fan favorite base layer made from 100% ZQ Merino wool. Ideal for cold-weather activities where warmth and breathability are crucial.
Moisture Management
Technology
Odor Resistant
Technology
Body Temp Regulation
Technology
100% Merino Wool
Fabric
Start-Stop
Activity
Cold
Temperature
Size Guide
Women's Classic Thermal Merino Base Layer Crew
InCm
Women's Clothing Size Chart
Size
X-Small 0–2
Small 4–6
Medium 8–10
Large 12–14
X-Large 16–18
Chest
32–33" 81.5–84 cm
34–35" 86.5–89 cm
36–38" 91.5–96.5 cm
39–40" 99–101.5 cm
41–44" 104–112 cm
Waist
24–25" 61–63.5 cm
26–27" 66–68.5 cm
28–30" 71–76 cm
31–34" 78.5–86 cm
35–38" 89–96.5 cm
High Hip
31–32" 78.5–81.5 cm
33–34" 84–86.5 cm
35–36" 89–91.5 cm
37–39" 94–99 cm
40–43" 101.5–109 cm
Hip
35–36" 89–91.5 cm
37–38" 94–96.5 cm
39–40" 99–101.5 cm
41–43" 104–109 cm
44–47" 112–119.5 cm
Inseam
29–30" 73.5–76 cm
30–31" 76–78.5 cm
31–32" 78.5–81.5 cm
32–33" 81.5–84 cm
33–34" 84–86.5 cm
Arm Length
27–28" 68.5–71 cm
28–29" 71–73.5 cm
29–30" 73.5–76 cm
30–31" 76–78.5 cm
31–32" 78.5–81.5 cm
Size
1X 16–18
2X 20–22
3X 24–26
4X 28–30
Chest
43–45" 109–114.5 cm
47–49" 119.5–124.5 cm
51–53" 129.5–134.5 cm
55–57" 139.5–145 cm
Waist
39–41" 99–104 cm
43–46" 109–117 cm
47–50" 119.5–127 cm
52–55" 132–139.5 cm
High Hip
44–46" 112–117 cm
48–50" 122–127 cm
52–54" 132–137 cm
56–58" 142–147.5 cm
Hip
45–47" 114.5–119.5 cm
49–51" 124.5–129.5 cm
53–55" 134.5–139.5 cm
57–59" 145–150 cm
Inseam
30–32" 76–81.5 cm
30–32" 76–81.5 cm
30–32" 76–81.5 cm
30–32" 76–81.5 cm
Arm Length
31" 78.5 cm
31" 78.5 cm
32" 81.5 cm
33" 84 cm
Fit
Slim Fit
Follows the contour of the body.
Regular Fit
Room to move without additional bulk.
Relaxed Fit
Offers more room without being baggy.
Low Rise
Sits low on the hips, approximately 3 inches below the belly button.
Mid Rise
Sits high on the hips, approximately 2 inches below the belly button.
High Rise
Sits above the hips. Slightly above the belly button.
How to Measure
1. Chest
Measure under the arms, around the fullest part of your chest and back circumference.
2. Waist
Measure around your natural waistline. Keep the measuring tape comfortably loose.
3. High Hip
Measure around high hip circumference approximately 3 inches below natural waistline.
4. Hip
Measure around the fullest part of hip circumference, parallel to the floor.
5. Arm Length
With elbow bent slightly, measure from center back of neck, across top of shoulder, to elbow and down to wrist bone.
6. Inseam
Measure along the inside of the leg from crotch to ankle bone. Or measure a well-fitting base layer from crotch seam to pant leg bottom.
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Free Returns
Free Return Policy Smartwool offers free returns within 30 days from the date of purchase. Items must be unused, unwashed, and unaltered.
Store Returns Return the unworn item(s) to the store where you originally made the purchase for a refund or exchange.
Online Returns Return unworn item(s) purchased at smartwool.com 30 days from the date of purchase for a complete refund. Initiate a return by accessing your order history and selecting “Return Items."
Refunds may take up to 3-5 weeks to process due to the time often required for shipping and bank processing. Exchanges are not available.
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Free Shipping
We are currently offering free shipping on orders $89+ placed on smartwool.com.
Shipping based on normal carrier restrictions and delays. We cannot guarantee arrival. Offer is valid for the continental US excluding Alaska, Hawaii, Puerto Rico and any US territories, as well as PO Box addresses. Delivery days are Monday-Friday, excluding US federal holidays. Free shipping may not be available for some customers.
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