Classic Thermal Merino Crew Baselayer - Women's
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Classic Thermal Merino Crew Baselayer delivers unmatched warmth and next-to-skin comfort
What Our Gearhead® Experts Are Saying:
“This baselayer is a winter staple for me—soft, warm, and never itchy. It’s perfect for layering on cold ski days, and it doesn’t hold odor, so I can wear it all weekend without worrying about freshness.”
When the temperatures drop and the trail beckons, the Smartwool Classic Thermal Merino Crew Baselayer keeps us warm, dry, and comfortable through every adventure. Made from 100% merino wool in Smartwool’s heaviest 250gsm knit, this baselayer traps warmth while naturally managing moisture and odor, keeping us comfortable no matter how cold or active the day gets.
Flatlock seams and redesigned shoulder panels reduce rubbing under pack straps, while raglan sleeves add freedom of movement for skiing, hiking, or lounging fireside. Soft, breathable, and endlessly reliable, this merino crew is a winter essential we reach for whether we’re layering for a storm day or heading out for an alpine trek.
Details
- Warm, heavy-knit merino baselayer for cold-weather adventures
- 100% merino wool regulates temperature and resists odor naturally
- 250gsm fabric delivers substantial warmth without bulk
- Redesigned shoulder panels minimize friction under backpack straps
- Flatlock seams reduce chafing for all-day comfort
- Slim fit layers easily under jackets or fleeces
- Raglan sleeves enhance mobility for active pursuits
- Item #SWLZ8BY
- Material
- 100% merino wool
- Insulation Weight
- 250gsm
- Fit
- slim
- Center Back Length
- [small] 24in
- Style
- crew
- Anti-Odor
- natural attribute of merino wool
- Claimed Weight
- 7oz
- Manufacturer Warranty
- 2 years
Reviews
Q&A
Overall Rating
4.5 based on 30 ratings
Review Summary
Fits True To Size
Screen reader users: the following list provides a visual scale to illustrate the product fit. Please refer to the heading above for the fit type in text.Customer Images
Here's what customers have to say
The Smartwool base layer is a high-quality and versatile product that provides excellent warmth and comfort. Reviewers praise the softness, stretchiness, and overall comfort of the fabric, noting it is perfect for layering and keeping warm during cold weather activities. The fit is also a highlight, with the product running true to size or recommended to size up for a looser fit. While a few customers experienced issues with color or holes after repeated use, the overall consensus is that this base layer is a reliable choice for cold-weather activities and everyday wear.
AI-generated from the text of customer reviews.
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Selecting an option will reload the available reviews on the pageJanuary 1, 2026
Cozy, clean
I exerted myself skiing in this thermal and I got quite sweaty. The thermal shirt kept my body at a comfortable temperature and there was no sweat smell when I finished my ski runs (unlike the smells that come with synthetic materials). Thanks Smartwool!
Originally reviewed on Backcountry.com
December 29, 2025
Comfy and warm!
exactly what I wanted in a base layer - comfortable and keeps me warm
Originally reviewed on Backcountry.com
May 24, 2025
Warm and soft
- Familiarity:
- I've used it several times
Love it! So soft. Kept me super warm on my camping trip in the 20°F.
Originally reviewed on Backcountry.com
February 14, 2025
Warm warm and cozy
- Familiarity:
- I've used it several times
I love this base layer! It’s a nice medium weight. It feels like you have heavier protection than my lighter weight ones. I layer it with other clothing for skiing in temps in the teens in WA State and it keeps me warmer than some of my other lighter weight wool base layers. I also wear it for winter hiking with an added top and once again I’m warm. It’s also one of my go to tops for casual everyday wear since the design that I got is dressy enough to do so. I usually wear a XS but sized up to a small and it fits perfect.
Originally reviewed on Backcountry.com
February 6, 2025
Gotta love merino
- Familiarity:
- I've used it several times
Love!! Fun color and great functionality! Wore in 15 degree weather with a mid weight layer and jacket and it kept me warm while skiing.
Originally reviewed on Backcountry.com
January 12, 2025
Necessary buy
- Familiarity:
- I've used it several times
I purchased a top and bottom base layer for northern winter sports. The fit is perfect, the material is soft and comfortable, and the quality is worth the price.
Originally reviewed on Backcountry.com
January 5, 2025
Love it, super functional
- Familiarity:
- I've put it through the wringer
Just used it for the last month, including a trip Maine hiking, snowshoeing, dogsledding, sledding etc. I love the fit that it isn’t baggy, didn’t make me sweat when layered, and doesn’t smell after multiple days of activity - it became my go-to base layer in Maine. I really enjoy the ease of care with washing and drying and that it doesn’t “look” like a base layer. I can wear it with jeans around town and it’s really cute. It fits true to size with a bit of stretch to flatter but not be tight. I’m 5’3”, pear shaped/athletic and 130 lbs.
Originally reviewed on Backcountry.com
January 4, 2025
Warm and cozy
- Familiarity:
- I've used it several times
Perfect for layering
Originally reviewed on Backcountry.com
December 30, 2024
Warm, soft, and comfortable
- Familiarity:
- I've used it once or twice and have initial impressions
I got this to go with a pair of smartwool base layer bottoms. The top is very cozy and warm. Very happy with my purchase.
Originally reviewed on Backcountry.com
December 8, 2024
Perfect fit - size up!
- Familiarity:
- I've used it once or twice and have initial impressions
I am a 38C and usually wear an athletic bra that flattens my chest. I am usually a size M and sometimes a L. I sized up to a L and am happy with the fit. It's extra long in sleeves and length, but not baggy.
Originally reviewed on Backcountry.com
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