Thin and long tailed, with outer tail feathers almost entirely white (tail from below looks white). The bill is thin and pale gray. Breeding male: blue-gray above, including most of head and back.

With their large size, bold pied plumage, and fondness for open areas, black-billed magpies are easily seen. They hop and walk on the ground with a swaggering and confident gait. Monotypic.