A system, device, and method for plugging core holes. A core hole plug includes a top compression plate, a bottom compression plate, and a rubber expansion ring that separates the top and bottom compression plates. A beveled screw hole can be created on the top compression plate. The beveled screw hole matches the angle of the bottom surface of the head of a flat head bolt to ensure that the bolt remains flush with the top compression plate. The rubber expansion ring can be squeezed between the top and bottom compression plates as the flat head bolt is screwed into a threaded receiver nut formed on the bottom compression plate. An installation tool can be utilized to install the core hole plug so that the top compression plate remains flush with an existing floor surface.