It swims well, and in flight looks heavy, more like a goose than a duck, hence the English name. It is 63–73 cm long.
The sexes of this species are identical in plumage but the males average slightly larger. There is a fair amount of variation in plumage tone, with some birds greyer and others browner, but this is not sex- or age-related. A large part of the wings of mature birds is white, but in repose the white is hidden by the wing coverts. When it is aroused, either in alarm or aggression, the white begins to show. In flight or when the wings are fully spread in aggression, the white is conspicuous.
The voices and vocalisations of the sexes differ, the male having a hoarse, subdued duck-like quack which seldom sounds unless it is aroused. The male Egyptian goose attracts its mate with an elaborate, noisy courtship display that includes honking, neck stretching and feather displays..The female has a far noisier raucous quack that frequently sounds in aggression and almost incessantly at the slightest disturbance when tending her young.