Size: 5 to 6 metres. False killer whales are more slender and streamlined, and lack the striking black and white body pattern of the killer whales.
The head has a narrow profile and the lower jaw ends well before the tip of the rounded rostrum.
The flippers are pointed and have a distinct 'elbow' in the middle, and the dorsal fin , although much smaller than that of the killer whales, is still prominent and is distinctly hooked with a rounded tip.
There are 8 to 11 pairs of robust teeth in each jaw.
Most specimens are completely black but some may have a blaze of grey in the shape of an anchor from the tip of the lower jaw along the throat towards the navel and on the underside of the flippers.