A bathtub drain flange assembly includes a tubular drain flange fitting that has a radially-extending flange on an upper end and male threads on a lower end. A support structure in the lower end of the drain flange has an oversized or larger-than-normal opening, which is usually threaded. A reducing bushing is received in the opening and has a threaded bore that is one of a number of different sizes for receiving a plumbing device such as a drain stopper, a strainer or a drain cover. A bathtub drain flange kit includes a drain flange with a larger-than-maximum-standard size for an opening in the drain flange and two or more reducing bushings that fit properly in the opening and become fastened to the drain flange, where each of the reducing bushings provides a threaded bore that is a standard size for receiving a plumbing device.