We stand behind everything we make. We promise to make our products with incredible attention to comfort, fit, and durability—because we want you to love our gear as much as we do.
And we want it to be able to support all of your adventures, from exploring new cities to summiting new mountains. So if, for any reason, you aren’t completely happy with your Smartwool® gear within two years of purchasing, we’ll get you into some new gear. No problem.
100% Merino. 100% capable. Our Women's Classic Thermal Merino Base Layer Bottom is always ready for what's ahead and what's next. With...
View moreSee less
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
Slim
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
Fitted with a mid-rise waist
Merino-lined elastic waistband designed for comfort
100% Merino next to skin
Flatlock seam construction designed to help increase comfort and minimize chafing
Size medium inseam: 30.5" (77.5 cm)
Made in Vietnam: 100% Merino Wool. Exclusive of Decoration.
SW019242
Care
Machine Wash Warm Gentle Cycle.
Wash With Like Colors
Do Not Iron Decorations.
Do Not Dry Clean
Cool Iron As Needed
Tumble Dry Low
Do Not Bleach
Women's Classic Thermal Merino Base Layer Bottom
$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
Midweight: 250g/m2
Merino Content
Size Guide
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.
Find the size that fits you best based on people just like you.
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.
Apply for a Pro Program Membership
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.
Enjoy 15% off
Join our mailing list to receive updates and 15% off your first order. Terms Apply.
Thanks for signing up!
Your code should reach your inbox shortly.
Oops! This email address is already subscribed.
You are already set to receive the latest offers and news.
Upgrade to 20% off
Sign up for texts about all things Smartwool. Terms Apply.
Thanks for your digits!
Check your texts and reply Y to confirm your subscription.
