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Stay warm and comfortable with our collection of work and sport long underwear, designed for both performance and durability. Crafted from moisture-wicking materials, these essentials provide excellent insulation while keeping you dry during any activity. Whether you're working outdoors or engaging in sports, our long underwear offers a snug fit that moves with you. With a variety of styles and thicknesses, you can easily layer up for added warmth without sacrificing mobility. Gear up for any challenge with reliable long underwear that supports your active lifestyle.
$40.00
My son loves wearing these leggings on cold weather days. ... They made all the difference and kept him warm all day! ... They kept him warm under his soccer uniform without over
5
Ash1889
Bought about a month ago and definitely will be buying more to have on hand!
5
BigTT
Bought for flag football since it was pocketless. Fits great as both base layer and stand alone.
5
su22
Perfect for my Grandson under his football and soccer uniform
5
soniarg76
My son loves these. They are pretty thick so will be warm for the winter months. They seem to run true to size.
5
Jennifer Arnold
Great fit, amazing quality, perfect for my son for football
$30.00
performance fit pants brushed interior fabric offers all- day comfort and warmth body contouring design for great shape tag- free design provides a fuss- free
$130.00
slim fit is intended to follow the contours of the body crewneck long sleeves engineered construction uses knit structures to enhance performance with lighter weights and cleaner finish 3d mapping results in near custom fit and freedom of movement while ribbed elbows provide added...
$67.97
WAS: $90.00*
. feels good next to the skin ... This will be a great base layer for cold weather and great outer layer when the temps are cool or warmer. ... Bought a month ago and will use all
5
mwo131313
If you need a high- performance base layer for extreme cold, the UA Base 4. 0 ¼ Zip is one of the best options out there. Just bought my second one.
5
M2024
Great base layer, warm and comfortable
5
Jasonwithg
Good quality nice and warm
5
JKT91
amazingly, surprisingly warm.
5
Lawrence45
Purchased a Large. The fit& feel is nice. Only issue is it maybe a little too tight in forearms( if you like to roll- up your sleeves).
$44.97
WAS: $100.00*
The long sleeve shirt that goes with it is awesome too! ... They work great under my hunting pants. ... Love them, extreme warmth, so much warmer than base 3, I like the looser fit in the
5
Mand4
Comfortable and warm, like that they are black and can be worn as a base layer or outer layer
5
Mom2025
Got this for my daughter, she is a teacher. Keeps her warm through her sedentary day. We 've tried other products with little success. The 4. 0 is perfect.
5
GT1976
The Under Armour base layer are the best thermals on the market!
5
mob1032
These leggings are very warm and great for watching football games in the winter.
5
Kristy w
The best cold weather gear I have gotten yet!
$54.99
Perfect for layering under pants when working all day outside. ... They ’ re definitely not for extreme cold days, but they work good in average cold. ... Great fitting, warm layer
5
MDV43
Comfortable. They fit full length. I am 6' 3. They did n't shrink when washed and they are just overall pretty awesome for thermals.
5
NancyG
These thermals fit well and keep me nice and toasty when I 'm outside.
5
Ppinner
I bought this product as Christmas present for my husband
5
MarcosD
These are baggier than most thermals but work great.
5
Jack sprat
Recent purchase, worn a few times. So much better than my old pair of thermals.
$115.00
the technical benefits of 100% merino wool will help you keep your game at a high level for longer. ... slim fit 100% merino wool fabric made with an interlock knit for enhanced comfort, breathability, thermoregulation, and odor resistance fit updated to improve functionality while...
5
Kwhendy
Bought these about a week ago and wear them nearly every day. I love how they keep me warm but do n't make me hot.
5
Mountain time
Fit great especially in length. Perfect weight to stay warm in cold weather.
5
tjflan2
Fit true and worked outstanding as base layer for football game. Very comfortable and breathable.
$65.00-$130.00
WAS: $130.00*
Love it, it is light but warm I wear them all winter long ... Love this base layer pant to compliment the top. ... They 're very comfortable and keep me warm enough to enjoy the slopes for
5
abeck
[ I received these as a Christmas gift. I love them under my bibs for snowboarding! They ’ re tight but flexible and comfortable. They keep me warm on the mountain.
5
shellydk
[ I could go on and on about this whole line from Smartwool. It's their best thing in a very long time and I 've been a fan for years. The material is very soft, has a great but comfortable fit. These bottoms also have a nice wide and sturdy waste band so there is no bunching or other uncomfortable nonsense in that area. These are very warm, so perfect under a shell pant or bib for alpine skiing, but I do n't think I would wear them on a tour.
5
Hmae
[ Love the style. These are very warm and keep me toasty on those cold days. Would recommend to anyone looking for a quality under layers... very cute!
$44.99
They 're warm, comfortable, and definitely work for my vet calls. ... crewneck long sleeves concealed thumb loops hold the sleeves in place mid- weight polyester and wool blend keeps you warm and regulates temperature smooth flatlock seams reduce chafing tagless...
5
AnthonyV
Very comfortable and warm, while also lightweight, perfect for a few days on the slopes!
5
Denise
[ Keeps my husband warm when he works outside! Will purchase more
5
SOCORROV
They are a Christmas gift but the material is awesome.
5
ArturoR
It is amazing, kept me warm when the tempt dropped to 17°F
5
Slim67
Lightweight, soft and warm, just what is need from a base layer
$55.00
Dicks sporting goods came through and the under armour cold gear worked as designed. ... these compression tights were perfect for training sports, bought these for running and they sure do keep me warm on cooler mornings and
5
MamaToHayden
I purchased this for my boyfriend for Christmas and he loves it! He wears this for all his outdoor activities and he is never cold.
5
MamaChiTown5
True to size, comfortable. My son wears them while playing soccer.
5
Andrew E2
Got this gear to wear on those super cold days under the snow pants. They are thin and skin forming enough to not impact the fit of the boot along the lower leg( big deal for performance skiing) and warm enough to keep you on the mountain.
5
Ball pro
These leggings are comfortable to wear for everyday as well as sporting activities
5
Personal4
Great product for baseball and other sports. Works well I. Texas weather
$19.99
Nothing feels better than wearing long underwear during these long, cold, New Hampshire winters. ... Keeps my partner warm all day when he works outside in 30 and below
5
jman151
I bought this for a snowboarding trip in Colorado. Excellent product. Kept me warm in the mountain.
5
IslanderAC
Fits true to size. Does the job in maybe 50- 60⁰ weather to keep your legs warm.
5
Ebaker187
Kept me warm on a 3 hour winter hike! It was about 25- 30 degrees out too.
5
Michael 7
I bought these to wear on those cold days on the golf course. Excellent purchase. Works as designed.
5
AkScott
I took the Duofold pants with me on a three week visit to a cool place. I went out on hour and a half to two hour hikes in temps from 30 to 45 degrees. My legs stayed warm even on rainy days.
$36.00
quad- blend fabric technology allows heat retention to keep you warm ... relaxed fit long sleeve shirt ultra- soft brushed interior offers all- day comfort and warmth true comfort stretch for ease of movement non- deforming design helps hold the shape tag- free design provides a fuss- free wear...
$36.00
relaxed fit pants ultra- soft brushed interior offers all- day comfort and warmth true comfort stretch for ease of movement non- deforming design helps hold the shape tag- free design provides a fuss- free
$49.99
My husband needed a new pair of long underwear for work, and he loves them. ... I work in a freezer and these are very good at keeping my legs warm. ... I was so impressed I ordered a women's set for myself as I 'm also outside a lot for...
5
Michael prez
Great product. just as described. fast shipping and fairly priced
5
JeannineR
These are great, its the second pair I have bought for my husband. He works in a freezer all night long and these are great and really help to keep him warm.
5
Madison L Green
Bought right before it started getting super cold and so glad I did!
5
Mscole12
Bought for husband…Good fit, comfortable fabric, decent price.
5
DennisR
These fit great and feel soft. Keep me warm all winter long
$44.99
Wore these under snow pants in- 10 weather for ice fishing and they worked awesome. ... I bought these so I may continue playing golf in the colder
5
ThomasL
This base layer has been great in cold weather. They perform well enough that I do n't notice I am wearing them while working.
5
JamesY
They fit great and keep me nice and warm working outside in the wind all day.
5
Lando523
Wore these under snow pants in- 10 weather for ice fishing and they worked awesome. Definitely buying them again in the future!
5
Tanner2
These base layer bottoms are great for cold weather. Carhartt products never disappoint.
5
GolfmanNJK
I bought these so I may continue playing golf in the colder weather. I ’ m pleased with the results.
$49.99
mid- rise closest fit through the hip and thigh close to body, but never to tight for work smooth flatlock seams and tagless label enhance comfort strategic seam placement reduces
$39.99
I love how the back is longer and doesn ’ t ride up. ... this long sleeve base layer top offers quick- drying comfort and performance with its microfiber single layer engineering
5
Meals
Bought these specifically to wear while skiing in the Rockies in Colorado in January. They were soft and comfortable enough to wear around the base of the mountain when not skiing, and they kept me warm when was doing down the slopes. Have no complaints about this shirt. It was perfect
5
CHutson
I bought this to wear skiing in Tahoe and it kept me nice and warm in 20 degree weather. I love how the back is longer and doesn ’ t ride up.
4
Zephyr TX
I bought this for my teen to use as a base layer for skiing and sledding. It kept him dry and warm and fit him well. I bought a duofold base later too too and liked the duo fold a little better as far as stitch quality and material quality and the duofold material seemed a little thicker but I ’ m keeping this one too.
$44.99
dry® technology to wick sweat and dry fast built to move with rugged flex® stretch technology fights odors smooth flatlock seams, y- split waistband, and contoured front for comfort strategic seam placement to reduce chafing mid- rise sits just below the waist closest fit through the hip and thigh...
$115.00
Every item I have received and used from Smartwool works exactly how I need it to from their gloves to their jackets. ... My son loves wearing thermal bottoms for
5
Wesley on the Rocks
[ I highly recommend these for all of your snow adventures. I wear mine directly under my snow pants and they work perfectly for warmth and movement. This base layer helped me survive snowboarding in both Colorado and Canada. Buy a pair, its worth every penny!
5
Jordan
[ I ’ ve worn this pair of wool pants as a base layer a couple of times in the snow and stayed warm. They fit and feel great! I definitely recommend!
5
Joe1
[ Bought two pairs of these for a snow trip. Great feel and regulated temp perfect. Alternated the pairs and neither smelled after solid week+ of use.
5
Littlemisstexas
[ Purchased this for someone. They gave a thumbs up. I personally own a pair of women ’s smart wool. Money well spent. They last a long time, and they ’ re as comfortable as it gets.
5
Chris K
[ I bought this base layer bottom for a ski trip to Colorado. This did a great job keeping me warm in the cold mornings and wicking sweat away in the warmer afternoons.
$54.99
I am truly amazed at how well this bottom works to keep me warm. ... I am 5ft 3in, and weigh 115lbs, and the small works well for me. ... Nice fit and super
5
VickieG
These thermals are nice and warm and the fit is perfect.
5
JayCee
I do n't like reviews that say `` love these '' or some such, since it tells me very little. So... I am 5' 2 and weigh 152 pounds. My inseam is usually 28 inches, no more than 29. I ordered the large and they were perfect in length, landing right at my ankles with a little sag for give in the knees, and for squatting. I have a bit of a straight waist that is short- the waist band is about a 2 inch band that did NOT roll over or down and did not bind so the waist was just right. Fit perfect in the hips, and I have a butt so they stretched without gapping or sagging down in the back. I washed them in warm water, rinsed in cold and hung them up to dry. Dried quickly. They were warm without being hot, did not bunch in the crotch, and I had on jeans over them. Worked outside on the farm and stayed cozy. Went back and bought two more pairs.
5
LilyB
`` Heavyweight '' is a little misleading. The fabric is very thin and see- through. On their own, they do n't feel very warm, but worn under jeans or other pants as intended, they function very well. I forget I 'm even wearing them under jeans, and they keep me very warm on cold mornings. A good comfortable base layer. Got the M and they fit great. I 'm usually a 6- 8 in pant size.
5
GrizzlyGirl
[ Love the way they hug my buns and keep them warm. Great material and quality, fit is correct and would recommend these for your buns too, especially in Alaska.
5
ZaylahH
I wear them with the leggings and they keep me warm outside
$44.99
As far as the validity of the claims I can assure you that they are all 100% and if you have ever attempted to work in long John's these will be a game changer for
5
glasgirl65
Shirts are well made and comfortable. But I preferred the ones from the previous season. Not crazy about elastic thumb bands, they dig into thumb webbing on your hand. They were much more comfortable with the slash cuff thumb hole
5
Cupcake
[ I am 5 foot and have a lot of trouble finding regular small sizes( other than petite) that fit well in the length. This long sleeve is just right
5
MehganM
Love the deep purple, top base layer! It fit really well and was long enough despite my 5' 11 '' height. If you are a C cup or bigger, you might want to size up, but for anything smaller it should work. It's odd that this was long enough but the matching pants are not as I 'm very proportional. In any event, I 'm grateful to have this top and I love the feminine color! Thank you!
5
Katie
[ Bought one in wine and two in black. The wine fit perfectly but the two black ones were tight under the arm, so I returned them. Quality is terrific and it was well appreciated in the cold Montana winds last month.
5
Sesb2120
[ I purchased this shirt, and another in a different color, after having an earlier model. I ’ ve worn the shirts several times now and I ’ m very happy with them. I do think they run true to smallish in size so maybe order up a size.
$115.00
They are n't too long or too short, they do n't bunch up and they are comfortable on my waist while managing to fit nicely over my large hips. ... They are soft and warm and a great addition to my
5
Mrsfry
[ I recently wore them under my jeans in Sweden and it was the perfect combo. I stayed the perfect temperature inside and outdoors while walking around in December. I would highly recommend.
5
Kpave
[ These fit so great! I ’ m plus sized and sometimes sizing can be wonky or vague but these are a dream. They are warm for sure but I can ’ t wait until The temperature dips to really put tgem to the test.
5
Maw maw Z
My legs will not be cold this winter. They are of good quality and very soft and warm.
4
Rmrst40
These base layers are awesome! Super comfortable and warm under snow gear or by themselves! If the price point wasn ’ t quite so steep I would live in these all winter long!
$61.97-$115.00
WAS: $115.00*
Can wear all day long ... I tried a medium this time( I 'm 5' 2 '' and 140 ish lbs) and they feel super comfy, the small also works for me. ... Amazing for skiing, alpine or
5
posie
[ Very impressed by Smartwool after hearing from a friend. this baselayer is super lightweight and warm. good for running as it is or layering under a waterproof pair of pants for frigid weather to hike
5
Sdwvt
[ I now own two pairs of these bottoms. I sized up to a medium. I wear them under my snowboard shell pants. I stay warm and they do not bunch. They are versatile. I can wear them around the house and out for walks. I love them.
5
Toasty
[ Driving around all day when it ’s cold out delivering mail and packages to the door, they help keep me warm and moving along. Oh come on, thanks for everything.
5
Lydn
[ The perfect merino base layer and lounging bottoms. Not itchy at all but soft, comfortable and stretchy. I 'm 5' 1, 108 lbs and the S fits well, not skin tight.
5
Prp74
[ I bought this wear at night during a backpacking trip. Worked perfectly when the temperature dipped to 30. More comfortable than the smart wool 150 baselayer.
$77.97
WAS: $130.00*
I no longer have to wear multiple layers underneath a uniform to stay warm. ... Again, very well made and warm. ... Inside and outdoors, it's a great layer to be
5
Peter
[ The Smartwool Men ’s Intraknit Thermal Merino Base Layer performs as described. In addition, it is not at all itchy, yet warm and comfortable.
5
Pflan
[ Comfort, comfort, comfort and warmth. Fit perfectly. Nice and snug Now that I have a pair I won ’ t ever go without. Buying additional colors now.
5
Kimmer13
[ The base layers I bought were too thick so I sent them back and ordered another set. They notified me immediately my return had been received and the refund quickly followed. Great prices!
5
SeanT
[ Perfect fit and super soft! But these as a base layer and will be what I wear going forward. I also have two Smartwool tops that are amazing!
4
Zeejet
[ An excellent product with a compromise between the benefits/draw- back of PE and merino fabrics. My main criticism is the extremely high- cut waist that rides all the way up to the belly button. It should be about two inches shorter than it currently is. Fit( Men's Medium): Great in the legs but unusually high waist band. I 'm 5' 9 '', 165lb, 31 '' Waist, Climber's Build. Pros:+ Excellent wicking and drying times+ Warm+ Quality build Cons:- Unusual cut and fit at the waist- While already very soft to the touch, just a tad coarse compared to Icebreakers products.
$85.00
a year- round favorite, the classic all- season merino base layer bottoms work hard to keep you comfortable everywhere, from the ski lifts to the
$24.99
Bought these for skiing to go under ski pants and worked well. ... Keeps you warm ... He wears them every day and they keep him warm. ... I love them they are thin not heavy for laying a must buy brand if you want thicker and warmer thermal get the same brand in expedition version...
5
Lynn2025
I bought these for my son. He wears them every day and they keep him warm.
5
YOYO90
I love them they are thin not heavy for laying a must buy brand if you want thicker and warmer thermal get the same brand in expedition version military fleeced ok.
5
skiellen
Bought these for skiing to go under ski pants and worked well. Less expensive than most but did the trick. They do run large however. Large was huge!!! We ended up with a small for my son.
5
Socker mom1
Great product at a good price. We need to buy the shirt.
5
Tacomama
I bought these for my husband& he is very happy with the purchase
$29.99
Thermal bottoms keeping me warm ... This is the first time I 've purchased or worn these pants and I like how they feel. ... Wonderful fitting thermal bottoms arrived just in time for the
5
aggielre2000
Love these, kept me appropriately warm on the slopes
5
Seabass76
This is the first time I 've purchased or worn these pants and I like how they feel.
5
SteveJ19
Wonderful fitting thermal bottoms arrived just in time for the snow. Free shipping and three- day turnaround were pluses.
$125.00
relaxed fit made with four way stretch for unlimited movement moisture transfer fibers move moisture away from skin to keep you dry upf 30 protection clima- wool fabrics boast superb breathability and temperature regulation for a comfortable
$110.00
slim fit base layer bottoms high rise fabric combines moisture management, temperature regulation, and odor resistance of merino with the softness and cooling properties of tencel™ lyocell performance fabric mesh ventilation seamlessly knit in gender- specific zones designed to keep the body dry...
5
Jacketquestion
[ I was skeptical after reading reviews but I really like these tights. The waist is high and seamless and very comfortable. Also doesn ’ t dig in creating muffin top stretchy and warm. Looks great under skirts for winter. Totally recommend. Feels lighter than the coordinating tops. True to size.
5
JLKNH
[ Good fit, snug but very moveable, slightly more so than Intraknit 200, although both are awesome. Pair with waterproof( maybe) lightly lined pant for full winter warmth without the bulk. Love the fun pattern to make life more interesting. Highly recommend!
$130.00
merino sport yarn combines the power of merino with the durability and fast dry times of polyester mesh ventilation seamlessly knit in gender- specific zones designed to keep the body dry and
$140.00
free of plastic microfibers and petrochemical- based synthetics, this product is made with 100% pure merino fibers that were hand- picked for strength and softness to create a luxurious fabric that naturally breathes and resists
$41.97
WAS: $65.00*
I ’ ve been using them to stay cozy while social distancing outdoors, but also while snowboarding and they ’ ve been great in both cases. ... I bought this heavy base layer too and bottom and love the
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