A portable shower enclosure includes a base frame composed of a rear frame, a first lateral frame pivotably coupled to a first lateral side of the rear frame, and a second lateral frame pivotably coupled to second lateral side of the rear frame. A seat with a top surface opposite a bottom surface defines a drain aperture therethrough. One or more bumpers extend from the bottom surface of the seat and are configured to elevate the seat above a rim of a toilet bowl. A waterproof liner defines an aperture therein sized and configured to be positioned over the toilet bowl under the seat. The liner has a frame coupling assembly configured to adjustably couple the liner to the first lateral frame, the second lateral frame, and the rear frame.