The Cattle egret is a stocky bird. It has a relatively short, thick neck, a sturdy bill, and a hunched posture. The nonbreeding adult has mainly white plumage, a yellow bill, and greyish-yellow legs. During the breeding season, adults of the nominate western subspecies develop orange-buff plumes on the back, breast, and crown, and the bill, legs, and irises become bright red for a brief period prior to pairing. The sexes are similar, but the male is marginally larger and has slightly longer breeding plumes than the female; juvenile birds lack coloured plumes and have a black bill.
Migration in western Africa is in response to rainfall, and in South America, migrating birds travel south of their breeding range in the non-breeding season. Populations in southern India appear to show local migrations in response to the monsoons. Cattle egrets inhabit wetlands, dry grassy habitats, semi-arid steppes, floodplains, freshwater swamps, shallow marshes, and mangroves. They are often found in fields, croplands, and pastures with poor drainage. When nesting, Cattle egrets are found in woodlands near lakes or rivers, in swamps, or on small inland or coastal islands.