A triangular black area in front of the eyes extends to a black fleshy knob over the nostrils. Generally males have a larger knob than females which is most evident during the breeding season. The area around the nostrils and tip of beak are also black. The bill is bright red-orange fading to pink in non breeding birds. Legs and feet of the Royal Mute Swan are black to blackish gray.
Eyes are hazel.
Adult weight is from 25 to 30 lbs. Newly hatched cygnets have overall pale gray upperparts and white underparts. The bill is black and the feet and legs are pale gray. The down of the female cygnets and juveniles is dirty white instead of pale gray. A sex linked recessive inheritance causes the males of the Polish to have the normal or Royal Mute juvenile appearance with dark gray legs.