WASP-15 was first observed by the South African Astronomical Observatory, which coordinates the planet-searching SuperWASP program in the Southern Hemisphere (WASP-South), and was catalogued by its brightness and its coordinates in the sky.
Data processing led to the acquisition of 24,943 data points that suggested that some body transited, or crossed in front of (and briefly dimmed), WASP-15 every 3.7520 days.