Estimation of the distance of three transient X-ray sources characterized by a rapid increase to a flux comparable with the strongest galactic X-ray sources, followed by a slower decay over a time scale of three to four months. A simple argument based only on X-ray data is presented, which yields a typical distance estimate on the order of a few kiloparsecs. In particular, it is demonstrated that it is most unlikely that the transient X-ray sources can be extragalactic in nature and produced by supernova events in nearby galaxies.