An extendable shower seat. The extendable shower seat includes a chair having a back portion and a seat portion, wherein the back portion is perpendicularly affixed to a rear side of the seat portion. A frame is affixed to the lower side of the seat portion and a plurality of legs are affixed to the frame. A pair of sidewalls are each pivotally affixed to opposing lateral sides of the seat portion about a hinge, wherein the pair of sidewalls can pivot about the hinge when a button disposed on the hinge is actuated, and remain locked in the selected position when the button is released.