The yellow-billed stork is closely related to 3 other species in the Mycteria genus: the American woodstork (Mycteria americana), the milky stork (Mycteria cinerea) and the painted stork (Mycteria leucocephala).
Before it was established that the yellow-billed stork was closely related to the American woodstork, the former was classified as belonging to the genus Ibis, together with the milky stork and painted stork [REF].