The surf scoter is a medium-sized, cumbersome sea duck with a big head, sturdy neck, and heavy, broad invoice. The male is black total white patches on its nape and brow. The invoice is orange with black and white markings. Exterior of breeding season, the male loses the nape patch.

The feminine is darkish brown, with darker wings, and a darkish gray invoice. She has white patches on the face behind the invoice and behind the attention, which distinguish it from the velvet scoter.