The grey-headed flying fox is one of the largest bats in Australia, with the maximum recorded wingspan exceeding an impressive 1.5 m. This bat has a dark grey body, a paler grey head, and a conspicuous collar of rich russet-coloured fur encircling the neck. As with all members of the Pteropodidae family, this bat lacks a tail and has claws on the first and second digits. Uniquely, however, this species' body fur extends all the way down to the ankle, distinguishing it from other flying foxes (Pteropus), which only bear fur down to their knees.