I cut a slit in nearly all of my head coverings to accommodate my ponytail. However, I also wear a Giro Prolight helmet, which has a very nice elastic band at the back of the head instead of the usual plastic cinching devices that you normally find on bike helmets. Because of this elastic band that "gives", I don't feel that lump of ponytail on my head. But usually I just pull it through the slit that I cut in my hats and beanies.