I've been using this top for over 5 years now in cold weather activities. As everyone noted, it fits skin tight, but it's supposed to. I wear it as an under layer so it has never mattered to me how tight it is (although it takes a bit to get used to the tight feeling through the shoulders). This shirt is always dependable in cold weather, and breathes really well when you work up a sweat. I bought one in a different color last winter, but my first one is still going strong.

This shirt is super tight! Recommend sizing up. I ordered a small (I am 5'5 at 115lbs) and I had to squeeze myself into this one. I haven't tried it out yet, but I think it will do the job when running in the winter. I think definitely will be wearing something over this one, it is sooo tight!

In general, Under Armour shirts run extremely small and are pretty tight. However, I think they are supposed to be super tight on your skin in order to work better. So, if you can get over and accept that, purchase your regular size. But, if you (like me) hate the feeling of something that tightly wrapped around your upper body, I would definitely recommend ordering a size larger than usual (especially if you are large-chested).
Also, just as a side note, UA shirts run a little short, so don't be expecting them to sit very far below your waist.
All that aside, UA makes wonderful products. They work extremely well and look hot on. I would most definitely recommend this shirt or any other UA Cold Gear (and Hot Gear) to anyone.

This shirt is great. It keeps me nice and warm on my morning run. I bought a medium but probably needed a large because the shirt tends to ride up my waist, so I'm consistently pulling it down. (I'm 5'5"/125 pounds/36C) I would definitely recommend this product and have to agree with the other reviewers that Under Armour makes good products and they look great on.

I've been wearing UA cold gear for 4 years now, for horseback riding, running, and other outdoor activities, and this top is a staple. I mean, I couldn't do winter without it. It's the perfect under layer, keeping you warm while also wicking moisture. It's supposed to fit very tight, and it takes a bit to get used to the feeling, but I wear my normal size (medium), for what it's worth. (I'm 5'7, 130, 34A)

I am also 5'5" 115lbs, and I ordered a medium, but I still feel like this shirt is super tight! It took me a while to get used to the mock neck top, I felt like I was being strangled at first! I also found that it rides up when I wear it under something else that is tight fit. That being said, it does keep me really warm when I run and when I ski, but next time I will probably get a 1/4 zip shirt.

I recently bought this for a ski trip. It is a great layer to wear for cold weather activities. It kept me comfortable and dry. The arms fit pretty snugly, fyi.

I followed the advice of the other reviewers and ordered one size larger than the sizing chart suggested. It's been to the slopes once with me and have no desire to go back to my old base layer or try any new product. My upper body was completely dry and toasty warm while in motion and while standing still. At any rate, I'm 5'5"/135lbs/34DD and large was perfect. I've never bought an Under Armour product that I didn't love and this shirt continues that trend.

i never tried UA products before buying this shirt. it basically changed my life. there is nothing like going from running in layers of cotton shirts in the winter (which end up getting wet and cold) to the UA subzero. keeps me completely warm and dry. can't run without it. i want to get the pink one now...

After reading reviews and getting advice from others I decided to buy the UA Cold Gear top for a base layer to wear snowboarding. I am glad I got this shirt. It kept me warm and dry all day. I love how if I crashed and got it wet, within minutes of eating lunch it was dry.

Just wanted to say, what a wonderful product. I freeze all winter long. I have health issues and can't get warm at night. I wear this shirt too bed at night. Keeps my arms so so warm.
Thank you for this great product!