Adult Heaviside’s dolphins typically weigh between 60 and 70 kg, with an average body length of 1.74 m. Maximum girth is roughly 67% of the length of the body. Each individual has between 48 and 70 teeth. They are distinguished from other dolphins by their blunt head, robust body, triangular dorsal fin, and rounded paddle-like flippers. Heaviside's dolphins have a dark gray anterior surface with a dark blue-black patch beginning midway between the dorsal fin and the snout, and extending about halfway down the ventral surface of the body. White markings on their underside form a three-pronged fork, with another white rhomboidal patch on the chest and two smaller diamond-like patches just posterior to the flippers. They also have a dark blue-black stripe, which extends from the blowhole to the cape. Sexual dimorphism has not been reported in this species.

Range mass: 60 to 75 kg.

Average length: 1.74 m.

Other Physical Features: endothermic ; homoiothermic; bilateral symmetry

Sexual Dimorphism: sexes alike