â
Stay warm and cozy with our collection of the best thermal shirts designed for ultimate comfort and insulation. Crafted from soft, breathable materials, these shirts provide excellent moisture-wicking properties to keep you dry during chilly days. Perfect for layering or wearing on their own, our thermal shirts offer a snug fit that retains heat without sacrificing style. Whether you're heading outdoors or lounging at home, these versatile essentials are a must-have for your cold-weather wardrobe. Embrace warmth and comfort with our top-rated thermal options.
$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. ... I was amazed how warm and comfortable this
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!
$55.00
This shirt is great for wearing as a base layer or on its own. ... I bought this as an undershirt for my son to wear under his uniform and it kept him plenty
5
dmitch1989
used it for my sons baseball game kept me very warm good material
5
Roxtar
My daughter loves this when she plays golf and its cold
5
brother shoes
I wore this cold Gear due to our cold spring soccer games and it kept me warm.
5
Danielle Harris
The quality of product was great. The fit of item was accurate according to description.
5
Guido10
Daughter got this for her game in 22 degree weather and was good!
$56.98-$120.00
WAS: $120.00*
The softness and temperature regulation make this my favorite baselayer. ... I am so glad that SmartWool has decided to offer plus- size clothing for women and I hope they expand with even more
$56.23
WAS: $100.00*
I love it besides the thumb space. ... Could n't be happier with the warmth. ... I work in a meat room and it ’s very cold, I only have to wear my base 4 shirt and my work tshirt and I ’ m kept
5
Mom2025
Got this for my daughter, she is a teacher. Her room is cold and then she has bus duty periodically. So the 4. 0 is perfect for being somewhat sedentary. Surprisingly, actually keeps her warm! She is a chilly person normally, so cold temps are miserable for her. We 've tried many products. The Under Armour is work the investment!
5
KarenK11
I am always cold. This is the solution! Love it!
5
East Coaster
These are the best long underwear going. I mind the cold but not when wearing these.
5
Jea970
The fit is loose but not so lose that I would exchange for a smaller size. The shirt is warm but not too warm when inside. Outside it keeps me toasty at 30 degrees and I ’ m always complaining of being cold. All in all, I ’ m very happy with this purchase.
5
I recently purchased the Under Armour Base 4. 0 Crew, and it's exceeded expectations. This top delivers comfort, warmth, and performance.
$32.98
WAS: $70.00*
These thermals fit great, feel awesome and meet all my expectations in function. ... Perfect for winter ... I work snow removal and this was perfect to wear. ... Warm 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.
$50.00
normal fit, nice bright aqua color, very comfortable! ... Bought this shirt about 3 week ago very comfortable soft fit really well ... Great fit, light weight, warm&
5
Lakasto
I love my new top. It is warm and easy to wear when I work out.
5
Bumblebea
I bought this a few weeks ago and the material is really soft and keeps your warm! Love the colors, I got green
5
JSSQFoley
this crew is amazing- comfy, warm, the material just melts on you. fits boxy which i like. def recommend it.
5
KMG411
Thin warm base layer. Great for outdoor training in the winter
5
Ne ce
I bought this a month ago and it ’s a great shirt very soft
$55.00
Good balance of warmth and comfort. ... He said it was very warm and felt great underneath. ... Keeps you warm during chilly Spring games without constricting range of
5
RicoGerardo
Used this shirt under my winter jacket for a trip to Yellowstone and kept me warm throughout the day. Would highly recommend as an inner shell when out in the cold.
5
iony boy
excellent product higt quality
5
CaptDave13
I really like this shirt at the gym. It ’s very light and comfortable. Fits loose which is perfect when working out. I would recommend this shirt even for hanging out.
5
K Saucier
Bought for a trip to Alaska. It kept me warm the entire trip.
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.
$62.00
This shirt is made with such a nice soft material! ... Love the feel of the fabric. ... Comfy ... Soft and warm ... Material is super soft. ... This shirt is true to size and
5
MemaJo
Will not likely wear before the fall season, but it seems perfect for skiing- light fabric for packing, but plenty of thermal warmth. The color was lovely too- subtle rose!![ for layering... sleeves were not super long, so not need to stuff under your jacket.] Would also come in handy alone for fall golf! Also a great name for teens- I got one for my 16 yo granddaughter as well.
5
CowboysforGolf
I purchased this for my wife and she loved the quality and how the material feels.
5
KSC41
I have bought several of these and wore them all winter and even on my trip to Europe and Switzerland and daily on the farm. They are warm and cozy and very comfortable to layer.
5
Stephhr71
Very soft and comfortable. Fits true to size. Recommend for those chilly mornings for your workout.
5
Farmgirl56
I purchased this for myself with a Christmas gift card. I love the fit and the weight( medium)
$52.48-$61.48
WAS: $110.00*
regular fit long sleeve
See Price in Cart
WAS: $155.00*
this bulk- free, 100% merino wool thermal layer brings a new dimension to active winter wear ... insulation, articulation, and ventilation are seamlessly integrated to help with movement and comfort during high- intensity
$159.99
The best thing ever. ... Quick delivery, charges great, and heats up quickly. ... He was very impressed with the smaller flat battery. ... It keeps me so warm and cozy and I couldn ’ t imagine life without it
5
Renee
You don ’ t realize how much you need a heated base layer until you have one! It ’s been such a benefit to various aspects of my life. I wear it beneath my layers when spending time outdoors during winter in Wisconsin. But I ’ ve also worn it to work( in an office) during especially cold days. It fits true to size and is comfy. Somehow it seems to trap heat inside yet it ’s also breathable, I don ’ t sweat in it like I have with other base layers.
5
The Base Layer Shirt takes the bite out of any cold day! And the battery last for hours! Washed it in a cold wash then hung it to dry, easy peesey! Definitely worth it!
5
I bought the base layer for my son who works at Disneyland in Anaheim Ca. and he loves it. Keeps hos 3X body warm when working nights. Great product
5
GLWS
Just wearing the shirt and not on has been enough to keep me warm. The few times I have used the heat, I set it on lthe lowest setting and was plenty warm.
5
Luke B
Definitely worth having extra battery banks if you ’ re skiing all day or anything like that, also could use an extra hole in the battery pouch so you can route the cable to a pant pocket more easily. Besides that, it definitely lasts through the wash and multiple winters
$75.97-$120.00
WAS: $120.00*
slim fit top contour the body heavy base layer top and best base layers for cold weather made with interlock knit for enhanced comfort offset shoulder and side seams to increase comfort and minimize chafing side seams wrap to front for body- enhancing fit temperature regulated:...
See Price in Cart
WAS: $115.00*
# Sweepstakes After having their all season or originally 150 merino clothing, this thermal merino is perfect for those cold morning runs. ... The best. ... This shirt was so soft and
5
Patches
[ Needed a thicker base layer for skiing on those colder days. Perfect addition.
5
Captain Jimmy
[ This base layer is really comfortable. It is warm and does not restrict movement. I wish I had found this earlier. Fit is true to size. I 'm not sure why anyone would not be happy with this- buy it!
5
Jbear
[ Merino is THE stuff for active comfort in the cold. The key is staying dry between rain, snow, and sweat... it's challenging. 100%( 95 and 88 also good) merino helps to achieve this goal. It's warm when you need it to be and water( all types) evaporates quickly to keep you from getting chilled from damp clothing. It's got to be part of a system though, and you have to use that system properly or you will get damp and cold. We just came back from five nights in our tent@ an avg. of 26F at night. After hiking all day in these and then, putting on fresh Smartwool tops and bottoms we were warm all night( we could have stayed in the same set if we had to). Medium weight is probably fine for most applications, but do be sure you 've got the right system for the conditions. In summer and spring it's less critical, but in winter( THE best time IMO)... having the wrong gear can make for a miserable experience... and a dangerous one. Smartwool has the added benefit of being able to go in the dryer at home... not all merino products can. That's my take.
5
JKNOR
[ When it comes to staying warm during the winter, base layers are KEY! My old Smartwool long- sleeve lasted me years of use. Loved my first one so much that when it came to finally replace it, it was a no brainer. Kept me comfortable and warm during winter months of New Zealand, Japan, all the way to the summit of Mauna Kea. I 've never had a base layer fit so good right off the shelf. Felt like it I was putting on my favorite tshit. Could n't recommend it more
5
Sheri
[ My son loved the wool sweater I bought him for Christmas. It was soft and warm at same time. Mmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm
$33.97-$38.97
WAS: $108.00*
fit& design our slim fit is intended to follow the contours of the body flatlock seam construction and offset shoulder and side seams designed to help increase comfort and minimize chafing offset shoulder and side seams designed to increase comfort targeted mesh ventilation technology fabric...
5
mullimullimullis
Fit is great, typical Merino, lightweight, and great as a base layer. Purchased on sale and a good value.
$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...
$100.00
machine wash ... knit™- engineered body mapped technology? to regulate your body temperature and? let your skin breathe during high- intensity activity cool- lite™- a lightweight and breathable fabric blend raglan sleeve construction for mobility gusseted underarms for mobility and comfort thumb...
5
Mark
[ I am getting synthetic products out of my wardrobe and I have become addicted to Icebreaker long sleeve layering shirts. They are extremely comfortable, come in a variety of nice colors and weights, so are quickly replaced my synthetic top layers.
5
The Greek
[ This is one of two or three of the most amazing clothes I have. Technically it's a base layer but it's something I wear almost anywhere with the right pants and shoes. It's wool, but it's incredibly soft and comfortable. It works great as a base layer, but it's versatile.
5
Fredrick
[ This color is perfect, very beautiful and should be used again and again. Ideal light weight garment for fitness. Very breathable.
$49.99
mizuno drylite® moisture management: using a dual filament yarn construction to transport excess moisture away from the body to create a comfortable and dry body microclimate for
$130.00
The garment care is oh so easy. ... Perfect Top for Layering orWearing Alone ... The styling is also extremely flattering. ... I love the length of the body and the
5
Camper at heart
[ The black cherry color is very flattering. I ordered based on true body measurements and the size chart resulting in a perfect fit. The styling is also extremely flattering. The neck is not too tight and not too loose. I love the length of the body and the sleeves. The garment care is oh so easy.
See Price in Cart
WAS: $115.00*
add one of our best base layers for cold weather to your winter wardrobe and experience the difference the next time you go skiing, hiking, climbing, or
5
Mele
[ I bought this for a gift for my daughter who works outside in Oregon winters with the horses. She loves it- Warm and cozy and fits like a glove! great base layer! Smart wool has been my go to for years!
See Price in Cart
WAS: $115.00*
add one of smartwool's best base layers for cold weather to your winter wardrobe and experience the difference the next time you go skiing, hiking, climbing, or
$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
See Price in Cart
WAS: $120.00*
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 flatlock seam construction to help minimize chafing as well as help keep you comfortable and temperature- regulated as you...
$120.00
women ’s regular fit themal interlock knit fabric set in sleeves thermoregulation and
$24.62-$44.99
WAS: $44.99*
Best Thermals I have ever worn! ... These are honestly the best thermals I ’ ve ever worn!! ... Best thermals you ’ ve ever worn!! ... I received the Base Force Midweight Tech Crew Thermals as part of a Carhartt Crew field test and...
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.
$34.99
It is warm and comfortable. ... Very comfortable! ... LOVE❤️Love these things don ’ t sweat keeps me warm and dry makes me wan na cry reach for the sky ... Very warm More like a
5
Firelion
I bought this baselayer to use for my recent snowboarding trip. The weather was windy and 8 degrees each day. I already owned the baselayer pants which were military issued. This top was perfect. It kept me warm for 3 days. All I used was the baselayer and a hoodie with my ski shell over the top. Perfect setup all day long.
5
Mike2380
Nice warm shirt. Not too thick. Very comfortable!!!
5
MercManSniper2A
LOVE❤️Love these things don ’ t sweat keeps me warm and dry makes me wan na cry reach for the sky
5
LabDad
I have used ColdPruf gear for about 3 years. Living in the northeast it gets cold. These products can not be beat. I highly recommend them to everyone.
5
mal517
Very satisfied with this item. It is warm and comfortable.
$44.97-$98.00
WAS: $98.00*
The best feature is the sleeves that can turn into two different lengths of gloves. ... It is the best lightweight jacket. ... Best winter running hoodie ... I also love the hood and the zipper at the neck, as I wear this as my base layer when...
5
YaelE
Very comfortable, Keeps me warm, great cover for the hands. love it.
5
RaechelD
Love this hoody for cool, windy, or rainy runs. It ’s very soft and warm! I wore it on my first 50K and it was incredibly comfortable. The sleeves are long enough for the thumb holes and the pull over hand warmers are nice if you didn ’ t bring gloves.
5
AuroraG
My new favorite hoody to run in for chilly weather! height 5' 2 115lbs size XS is perfect for me
5
KellyI
Wonderfully comfortable for these cold months, without being heavy or bulky. Has definitely become a staple piece in my running wardrobe. Medium fits perfectly( 5 ’ 10 ”- 155 lbs- typically size 8/10)
5
KimberlyM
Great midweight layer for Saturday morning long runs in the South. I wear it alone for temps in the low 30s. Love the pretty lavender color. Also just enjoy wearing it for casual wear on non running days.
$92.00
relaxed fit four way stretch for unlimited movement activated carbon enhances thermal regulation and odor blocking properties upf 30 protection moisture transfer fibers move moisture away from skin to keep you dry soft hand feel makes it easy to layer
5
Bevshaffer
[ Love this. I wore it under a ski jacket for snow skiing and it was super comfortable warm and fits great. I ’ m 5 ’ 2 ” and 140 pound and a medium fit great.
$130.00
odor resistance ... men ’s relaxed fit top interlock knit fabric breathability and thermoregulation drop shoulder
$41.00
this kids' thermal top is also knitted with mtf soft spun polyester fibers that transport moisture away from the skin to keep you warm, dry and
$64.95
fit and design interlock knit crew neck with set- in long sleeves flatlock seam construction designed to eliminate
5
Toasty
[ I bought these for my grandson for skiing and he likes to wear them like a sweater at times. What more do you want, warmth and some style. He loves them.
5
Nana
[ I purchased these for my grand daughters, to provide extra warmth without extra bulk, for our cold Michigan winters. They love sledding, playing in the snow and hiking with their mom, dad and brothers.
5
bethr524
[ I bought this Smartwool baselayer top because I really needed something that would wick the sweat away when I was exercising outdoors on those chilly days. This top does exactly what I want. It's soft and comfortable and keeps my core dry even when I sweat beneath other layers. It washes up easily and does n't retain odors. I 'm very happy with this item.
5
WI_Dad
[ Bought for our 5 year old daughter to use while skiing in UT. She is very picky about colors and general comfort but she loved this smart wool baselayer. So far has held up to washing as well. Will buy another when she outgrows this one.
$85.00
stay warm on those chilly morning runs in this top. ... nike therma- fit technology helps manage your body ’s natural heat to help keep you warm in cold- weather conditions thumbholes let you extend your coverage and help hold the sleeves in place while you move collar stretches to add face...
$75.00
moisture transfer fibers move moisture away from the skin to keep you dry and comfortable built- in 4- way stretch allows for full range of movement in every direction activated carbon enhances thermal regulation and odor blocking properties upf 30 protection blocks the sun ’s...
$105.00
regular fit comfort active stretch seam construction seams set away from shoulder for added support zip through collar with interior wind flap for ultimate warmth moisture transfer fibers to wick away moisture from your skin thumbholes in sleeves to help keep sleeves in place 4- way stretch for...
$90.00
Nice lightweight shirt ... Great dor working out and very comfortable under a sweater for cooler days. ... knit™- engineered body mapped technology? to regulate your body temperature and? let your skin breathe during high- intensity activity features cool- lite™, a lightweight and breathable fabric...
5
Chuck
[ Really love the shirt. It looks an feels great. I like everything that I 've bought from Icebreaker.
5
Max
[ No merino wool company compares to that of icebreaker. It feels fantastic while still maintaining all the qualities of merino. I have no complaints about this shirt.
5
BJ
[ Bought this shirt to run in and it's great. Comfortable fit, true to size and dries quickly when the sweat gets going.
5
JJJL
[ blending with TENCEL making it more comfortable, also no funky smell in the summer.
5
CAL
[ The most comfortable shirt I own and I really enjoy the way the material feels. I also own the `` normal '' ZoneKnit shirts and I had problems with the fabric tearing easily. This has held up better.
See Price in Cart
WAS: $130.00*
slim fit to follow contours of the body made with merino sport yarn: combines durability and fast dry times of polyester seamlessly knit mesh ventilation designed to keep you dry and comfortable 3d mapping provides maximum mobility ribbed elbows provide added durability mesh zones for better...
5
LPaul
[ I was looking for wool thermal layer for my husband, who runs cold. Rather than settling on a bland look, I chose this colorblock version for its added style. While he does n't fill it out quite as nicely as the model(!), he looks great in it.
5
rahoran53
[ I bought the Smartwool to keep me warm and comfortable on a 12 day trek in Nepal. The performance was outstanding and, as advertised, it was very breathable to keep me warm and even cool in the afternoons. It has a very comfortable feel and looks great as well.
See Price in Cart
WAS: $140.00*
our most advanced performance base layer is 3d- knit to provide a tailored fit with mesh ventilation to balance warmth and breathability ... insulation, articulation, and ventilation are seamlessly integrated to help with movement and comfort merino sport yarn helps combine the moisture management,...
$126.99
WAS: $150.00*
loose fit wide, ribbed neckline knit wool fabric feels cozy off the mat, keeping you dry and your muscles warm during recovery embroidered swoosh logo at center
$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
$130.00
insulation, articulation and ventilation are seamlessly integrated to amplify movement and comfort during high- intensity activities ... slim fit merino sport yarn combines the power of merino with the durability and fast dry times of polyester seamlessly knit mesh ventilation designed to keep you...
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. ... size medium center- front zipper: 10 '' ''( 25 cm) machine wash warm gentle cycle wash with like colors do not bleach tumble dry low cool iron as needed do not...
$55.00
the fairfax thermal hooded long sleeve is a cold- weather staple built for comfort and style. ... machine wash cold( 30c), gentle cycle use non- chlorine bleach if needed tumble dry low cool iron dry cleanable do not iron
Continue browsing
(4) 
