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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.
$47.98
WAS: $100.00*
I wear these for while working outside, and they do a great job of keeping me warm while I ’ m doing light work. ... Works perfectly as a light undergarment for my scuba dive dry
5
Fits like a glove, great material, true sizing.
5
SK719
Keep me warm while doing ice rescue training
5
JohnG111
Absolutely amazing- wore on single digit weather and only my hands and feet were cold
5
Dh2207
I bought these for my boyfriend who is an avid hunter and Lineman, he loves them! They keep him warm without getting sweaty!
5
Jm6990
I don ’ t like wearing a coat in Wisconsin. I wanted a solution that provided warmth while still fitting my aesthetic. This base layer 4. 0 has been perfect for me. It ’s fitted, not bulky and makes a huge difference in keeping my chest and arms warm with just a long sleeve on top of it. I recommend!
$56.23
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!
$47.98
WAS: $100.00*
These leggings are a great liner for under work clothes and for outside activities. ... fit fitted leggings inseam: 30 1/2 ” technology ua base™ 4. 0 locks in your body ’s heat to deliver extreme warmth even in the brutal cold moisture transport system wicks sweat and dries quickly...
5
Jeff1540
If you play cold weather golf you really need to get the UA Cold Gear product. I like it because it ’s flexible and fairly warm.
5
Prof13
My Under Armour- UA Base 4. 0 XL fits perfectly. The waiste band is comfortable. The fabric is a great barrier to the damp cold air near Lake Michigan as I watch my son ’s Zion Benton High School ’s Varsity baseball games.
5
MattB13
Very warm. Different than the old waffle style. But they still work just the same.
5
Amazing pair of pants
I work outside. And theses pants are amazing.
5
Great material. Fits like a glove. Perfect for cold weather. True to size.
$38.98
WAS: $70.00*
This cold gear 3. 0 works great in cold weather. ... fit fitted baselayer technology ua base™ 3. 0 all season baselayer is extremely versatile, providing midweight warmth and mobility to a variety of activity levels and cold temperatures moisture transport system wicks sweat and...
5
NonaElk
As expected wonderful. It ’s my third one
5
Rtin93
Great material fits really well Definitely going to be useful when worn during colder weather and feel like going for a run at the time
5
BiaE
Really warm underlayer. Used to ski on freezing temp and this plus good ski jacket was enough… even when it was snowing… The only thing is that it feels way different then the 2. 0 shirt. I also have one of that and the 3. 0 is more stiff and feels smaller. Specially in the neck and chest.
5
mrsguzzie
I purchased this Base Layer 3 shirt when I visited our local outlet store to place an order for another Under Armour shirt I liked. This shirt is thicker than a normal under layer shirt but is still comfortable if you wanted to wear additional layers. The cut of the shirt is super nice you might not want to hide it, though! It has thumb hole openings which are nice. I wore it alone several times since I bought it and was pleased at how well it kept me warm. I liked it so much I went to get a second one. They had sold out of the 3s but I snagged a 2 at least! My only negative comment would be it looks wrinkled when you remove it from the dryer. I only air dried it so maybe some heat might have gotten the wrinkles out. It's black so not that noticeable. Great shirt. I tried to get a 2nd one so obviously am happy with my purchase!
5
Stacy321
My husband has a few base layers and he loves them. I love the women's cut/size. It fits well and is super warm
$39.73
WAS: $70.00*
Easy to put on it ’s a base layer that you can wear as long johns under your clothes love ❤️ love love them ... They work perfectly. ... This product is so
5
Barn girl
I bought these for my niece in fargo north Dakota. It's- 45 degrees around chill this week. She says they are great for the cold weather where she does out side work in a barn.
5
vanheelj4
My daughter uses this for Nordic skiing. Lightweight and keeps her warm without limiting mobility.
5
Mrs Marcellini
truly a must have warmer if you are a skier or like to be in cold weather! I had used these for years and I am so happy with them!!! Just buy! true to size, I am usually a XS/small and got a small on these.
5
Dmjdavis
These keep you so warm and they are so comfy
5
Soccermom7406
Fit true to size. Nice material
$38.98
WAS: $70.00*
Excellent warm up leggings if you are working outside in the cold weather ... fit fitted baselayer leggings inseam: 30 1/2 ” technology ua base™ 3. 0 all season baselayer is extremely versatile, providing midweight warmth and mobility to a variety of activity levels and cold...
5
Rickiuyv
I got a pair of this ones and i really like them specially to be worn under layers for extra cold days, good material and thin can be use with jeans.
5
Tawhid
This product has soft and comfortable fabric!
5
Proline1988
Whenever it's cold outside and I have to be out in the elements for extended periods I always wear UnderArmour products. Nithing words as good to help keep me warm. A bit pricey but we 'll worth the money.
5
Mf1969
Warm and comfortable sizing was good. Good on cold days for sure
5
Anne799
My son wears these under his uniform. He is so happy with the comfort and layering capabilities the material provides!
$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.
$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
$28.48
WAS: $60.00*
I bought the 2. 0 base layer a few years ago and they 're my go to long underwear for the extreme cold. ... fit fitted baselayer leggings inseam: 30 1/2 ” technology ua base™ 2. 0 active baselayer is lightweight, flexible, and breathable for high activity performance in cool...
5
Tracey2020
These under armor thermals are a family favorite.
5
Mcdavid97
The base layer fit comfortably nice and snug. It kept me very warm as I was skating out in the cold winter weather.
5
Jdog523
I 've been wearing under my pants and they 've kept me warm during 0 degree weather
5
Avery111
These are great for my winter garage workouts. Slim layer fit really well under joggers. I always size up for tights and they fit nicely. Great amount of stretch, which I really need as a dancer.
5
LP25
Bought these for my husband and he loves them. He has a couple 3. 0 sets and has worm then for a least 6 years. They wear great.
$19.97-$40.00
WAS: $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
$33.73
WAS: $60.00*
fit fitted baselayer technology ua base™ 2. 0 active baselayer is lightweight, flexible, and breathable for high activity performance in cool conditions moisture transport system wicks sweat and dries quickly ua scent control prevents the growth of odor causing microbes to keep you feeling fresh...
5
Micheile
Feels great keeps you warm
5
NHummingbird
Very comfortable and good for mild to moderate cold weather. I would recommend
5
Brian31
This 2. 0 is comfortable and warm. Perfect baselayer to shred the slopes with. Wicks moisture as advertised. Awesome shirt
5
Jeff H 150
Great fit and very comfortable. Very warm when out in the elements but not too hot while working inside. Would definitely buy another one.
5
Kpax1
This base layer is warm, comfortable and lightweight.
$32.98
WAS: $70.00*
I work snow removal and this was perfect to wear. ... fit fitted baselayer technology ua base™ 3. 0 all season baselayer is extremely versatile, providing midweight warmth and mobility to a variety of activity levels and cold temperatures moisture transport system wicks sweat and...
5
JTBo
Excellent product…very warm
5
Base 3
Great feel true to size while being slightly snug which I prefer!
5
Kar1388
Super comfortable and snug fit. Perfect for cold weather
5
HB1153
I was pleasantly surprised by how warm this base layer really is. It made all the difference during outside chores this winter.
5
Proline1988
I work outside all year round minimum 8 hrs a day. I 've tried many different brands of long John's but nothing beats Under Armour Cold gear 3. 0. Keeps me warm and dry. Very comfortable to wear. Cost more than the traditional long johns but well worth it. I definitely recommend this product.
$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
$36.00
quad- blend fabric technology allows heat retention to keep you warm ... 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.
$50.98
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).
$61.97-$115.00
WAS: $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.
$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
$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.
See Price in Cart
WAS: $120.00*
merino sport yarn provides durability and fast dry times of polyester ... slim fit to follow contours of the body 3d mapping results in near custom fit and movement freedom seamlessly knit mesh ventilation designed to keep you dry and comfortable size medium inseam: 21. 5
$63.97-$85.00
WAS: $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
$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...
$61.97-$115.00
WAS: $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.
$36.00
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 crew neckline allows for a snug, comfortable
$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
$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!
$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...
$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.
$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
$110.00
They are very comfortable and made with excellent quality. ... Nice fit and feel ... Excellent buy. ... My wife loves the fit and feel. ... stitched on adidas terrex woven branding made with natural and renewable materials as part of our journey to design out finite resources and help end plastic...
$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
$73.48-$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!
$24.62-$44.99
WAS: $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.
$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
See Price in Cart
WAS: $120.00-$145.00*
we 've updated the fit of our men's classic thermal merino base layer 1/4 zip to improve functionality while also enhancing aesthetics. ... as one of our heaviest base layer tops and best base layers for cold weather, this garment uses 100% responsibly sourced merino wool, shoulder panels, and a...
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