Size: L: 150cm. Wt: Males: 11900 g. Females: 9400 g. Males and females similar, although males are somewhat larger. This species is not seasonally dimorphic.

Adult: body white; black facial skin tapers to point at eye; bill large, black, slopes continuously with head; neck straight, or kinked at base; legs and feet black.

Juvenile: similar to adult, but with grey plumage, and flesh-colored bill with black markings.

Cygnet: precocial and downy; down pale greyish-white or white, may be darker on lower nape, shoulders and wings; bill flesh-coloured or pinkish, with grey tip and edges; feet pale orange to yellow