The Glossy Ibis favors freshwater or brackish wetlands with tall, dense emergent vegetation such as reeds, papyrus, or rushes, and low trees or bushes. It can also be found in lagoons, floodplains, wet meadows, swamps, reservoirs, sewage ponds, rice paddies, and irrigated farmland. Coastal habitats like estuaries and salt marshes are less common for this species.
This ibis is the most widespread of its kind, breeding in warm regions across Europe, Asia, Africa, Australia, and the Americas. It is migratory, with European birds wintering in Africa and North American birds migrating southward. The species has been expanding its range, with increasing numbers in Europe and successful breeding in Britain as of 2022.