How to Choose Base Layers
Smartwool Classic All-Season Merino Base Layer Bottoms - Men's
This product is not available. Good news: we have a newer version.
Built for 4 seasons of adventure, the Smartwool Classic All-Season Merino Base Layer bottoms work hard to keep you comfortable on ski lifts and in campsites with their soft, durable merino wool.
Shop newer version- Soft, lightweight fabric offers next-to-skin comfort, moves sweat away from the body and acts as a versatile performance layer for warmer conditions
- Core Spun technology wraps merino wool around a nylon core for extra durability while still keeping the comfort of ultra-soft, responsibly sourced merino wool next to skin
- Merino wool content is ZQ-certified to help ensure environmental, social and economic sustainability while safeguarding animal welfare
- Merino-lined, 1.5 in. wide elastic waistband is designed for maximum comfort; it places 100% merino wool next to skin
- Flatlock seam construction is designed to minimize chafing
- Fully functional fly
Imported.
View the Smartwool Classic All Season Product LineView all Smartwool Men's Base Layer Bottoms| Best Use | Multisport |
|---|---|
| Fabric | 87% merino wool/13% nylon |
| Moisture Wicking | Yes |
| Fly Opening | Yes |
| Underwear Weight | Lightweight |
| Inseam (in.) | 31 inches |
| Gender | Men's |
Smartwool Clothing - Men's
| S | M | L | XL | XXL | |
|---|---|---|---|---|---|
| Chest | 36 - 38 | 39 - 41 | 42 - 44 | 45 - 48 | 49 - 51 |
| Sleeve Length | 31 - 32 | 32 - 33 | 33 - 34 | 34 - 35 | 35 - 36 |
| Waist | 29 - 31 | 32 - 34 | 34 - 37 | 38 - 40 | 41 - 44 |
| Hip | 36 - 38 | 39 - 41 | 42 - 44 | 45 - 48 | 49 - 51 |
| Inseam | 30 - 31 | 31 - 32 | 32 - 33 | 33 - 34 | 34 - 35 |
Sizing Notes
Measurements are stated in inches.
Buying Advice
More expert advice
Review this Product
Adding a review will require a valid email for verification
Most Helpful Favorable Review
Light on weight and heavy on warmth!
60 and climbing3 years ago
I have a pair of the 250 weight which I must say a very warm so I bought a pair of the 150 weight mainly to reduce my pack weight a little further. Mission accomplished! These are definitely lighter weight wise and also just as warm. I have zero regrets going with the 150’s. I use them as a base layer during outside activities and as part of my sleep layer when back packing. The quality is top notch with extra stitching around the stressful areas. Although I have never used the warranty, that gets another two thumbs up. Smartwool will definitely back up the product but thus far, these appear as though they will last for years,
60 and climbing
New England
6 people found this review helpful
Most Helpful Critical Review
low crotch
jakebrake3 years ago
Bought on sale so for the price I picked them up for they are not bad! I’m 5’10” 195lbs of average to athletic bulid, purchased mediums, waist and legs fit great however the crotch is way too low. To get a snuggler fit in the crotch area the waistband is just below my chest. I’d imagine for women this may feel normal but for a male it’s weird to have them up that high, if I lower the waistband to normal height it bunches up in the crotch when I put pants! Would not buy again.
jakebrake
MI
12 people found this review helpful
60 and climbing
New England
Light on weight and heavy on warmth!
3 years ago
I have a pair of the 250 weight which I must say a very warm so I bought a pair of the 150 weight mainly to reduce my pack weight a little further. Mission accomplished! These are definitely lighter weight wise and also just as warm. I have zero regrets going with the 150’s. I use them as a base layer during outside activities and as part of my sleep layer when back packing. The quality is top notch with extra stitching around the stressful areas. Although I have never used the warranty, that gets another two thumbs up. Smartwool will definitely back up the product but thus far, these appear as though they will last for years,
Age:55–64
Weight:200–225 lbs.
Height:6'1"
Yes , I recommend this product
Anonymous
Washington State
versatile layering option
3 years ago
These leggings are nice and light and form fitting so they fit well under jeans, shell pants, fleece etc. I normally wear size 38 pants and the XL was a good fit. They also have a fairly long inseam, which is great for us tall guys. I have a 34-35 inch inseam and they are plenty long. One issue that keeps these from being 5 stars is they are fairly high waisted so you don’t pull them past your waist they will sag in the crotch a bit. Also I would prefer these without a fly, as I do not use them so it’s just extra fabric and seams to bunch up. I should get lots of use from these as they seem very versatile base layer for different outdoor activities or just extra warmth under casual pants in the winter. They add a lot of warmth for how thin they are.
Age:45–54
Weight:200–225 lbs.
Height:6'3"
Yes , I recommend this product
jakebrake
Michigan
low crotch
3 years ago
Bought on sale so for the price I picked them up for they are not bad! I’m 5’10” 195lbs of average to athletic bulid, purchased mediums, waist and legs fit great however the crotch is way too low. To get a snuggler fit in the crotch area the waistband is just below my chest. I’d imagine for women this may feel normal but for a male it’s weird to have them up that high, if I lower the waistband to normal height it bunches up in the crotch when I put pants! Would not buy again.
Height:5'10"
Age:35–44
Weight:175–200 lbs.
No, I do not recommend this product
Francisco515
hayward ca
Great for when the day starts cold
3 years ago
I own a 250 base layer, but heat up quickly. On alpine starts for hiking, it'll usually be in the low teens and this is good enough. you'll be a little cold to start but after less than a mile it'll feel just right. For me, around 40 degrees it starts to get just a little too hot
Height:5'10"
Age:25–34
Weight:150–175 lbs.
Yes , I recommend this product
Anonymous
Houston, Texas
Smartwool Men's Merino 150 Base Layer Bottoms.
3 years ago
I bought these prior to a camp out and 10 mile hike with a weather forecast of 24 degree F. I don't experience cold weather like this often and had never camped or hiked in such weather before. I'm glad I made the purchase. I wore these in my sleeping bag, as well as under my hiking pants the following day. Fortunately, I selected the correct size and the fit was great. My hiking pants are slightly loose, so the added bulk of this base layer was not noticed even after 10 miles on the trail. Highly recommended.
Age:65–74
Weight:150–175 lbs.
Height:5'11"
Yes , I recommend this product
Melody May 90254
Hermosa Beach, CA
Best purchase ever
3 years ago
Best purchase ever! Comfortable- great base layer- kept me warm all day on the boat up in the Channel Islands, all day, after kayaking, I also slept in them!
Age:55–64
Weight:150–175 lbs.
Height:5'8"
Yes , I recommend this product
Eric
Adirondacks, NY
good but I like the Icebreaker version better
3 years ago
In comparison to the similar Icebreaker bottoms, these are higher waisted. Also, the diamond gusset in the crouch is wider than the Icebreaker. Between the two design differences, the Icebreakers are better for me.
Height:5'8"
Age:55–64
Weight:125–150 lbs.
Yes , I recommend this product
Pugwoman
Notrhern Virginia
Warm and lightweight baselayer.
3 years ago
Our 19-year old son loves these lacings. We bought them with the matching top for him. He is an avid hiker and loves that it is lightweight and fitted without being constricting. We highly recommend this set.
Age:18–24
Weight:125–150 lbs.
Height:5'7"
Yes , I recommend this product
Tim L
scottsdale
Cold weather gear
3 years ago
Another great piece from Smartwool. Simply one of the better base layer brands I have used for backcountry warmth and comfort.
Age:55–64
Weight:125–150 lbs.
Height:5'8"
Yes , I recommend this product
Nelson
Orlando Florida
Great base layer
3 years ago
Kept me super warm and dry during my first 14r in Colorado this Fall. Definingly worth the money!
Age:18–24
Weight:100–125 lbs.
Height:5'9"
Yes , I recommend this product
1 - 10 of 85 Reviews