If only regular socks fit as well; no bunching in the heel. I wear a size 7, 7.5 shoe so this is true to size for shoes 5 - 9. Addressing other reviews... mine was brand new, straight out of the package and bound. No snags or flaws whatsoever. I am 5 foot 2 and these pulled up come to about mid thigh on me. So comfortable, soft and warm. I usually like to be barefoot once home but I was actually able to keep these on.