Adult white-breasted waterhens have mainly dark grey upperparts and flanks and a white face, neck and breast. The lower belly and undertail are cinnamon coloured. The body is flattened laterally to allow easier passage through the reeds or undergrowth. They have long toes, a short tail and a yellow bill and legs. Sexes are similar but females measure slightly smaller. Immature birds are much duller versions of the adults. The downy chicks are black, as with all rails.