The yellow-billed egret was first formally described as Herodias brachyrynchus by the German zoologist Alfred Brehm with its type locality given as the Blue Nile (blauen Flusse).

In breeding plumage the yellow-billed egret grows long plumes on its back and breast and the normally yellow bill becomes orange red.

The lower legs and toes are dusky while the tibia is paler, becoming pinkish red for a short period during courtship before changing to yellow for the rest of the breeding season.

[6] The yellow-billed egret is typically encountered in seasonally inundated wetlands and grasslands as well as on the shallow edges of lakes, rivers, salt pans and in estuaries.

[7] Yellow-billed egrets are generally regarded as residents but they are known to undertake local movements to find more favourable conditions when water levels change.