Abstract: A rear zipper sock includes a generally cylindrical sock body having a foot portion, a generally upright leg portion and a heel section intermediate the foot portion and the leg portion with a rear open seam formed in the leg portion extending from the top of the leg portion downwards at least partially through the heel section, the rear open seam extending generally upright and parallel with the center upright axis of the leg portion of the sock body. A zipper closure device is mounted on the sock body adjacent the rear open seam, the zipper closure device operative for alternately opening and closing the rear open seam such that a user can open the zipper closure device and insert the foot into the foot portion without requiring significant bending of the ankle or knee during the fitting.