A convertible lift assembly is provided in which a vertical lift can be reversibly converted into a set of stairs. The assembly of the present invention uses less space than prior art system, and utilizes a set of movable side panels that can be contracted or extended to provide resting points for a series of stair panels. When in a contracted position, the side panels provide resting points in a stair configuration for the stair panels. When in an extended position, the stair panels are collected on a frame to provide an essentially flat, horizontal platform that can be raised or lowered on a movable frame.