what can I say, another great product by TS. I'm a UK 8, ordered size M. It fits ok, I love how the sleeves wraps neatly around my arms but the front of the shirt didn't sit really well? slightly tight, but no complains, doesn't bother me too much. If I ordered a size L it'll be waaaay too big. i guess it depends on how you want the fit to be. Love it nevertheless!