Bullsnakes are heavy-bodied reptiles with body length ranging from 1,2 to 1,8 m (4 to 6 ft).

Larger specimens can be occasionally found, up to 2,5m (8ft 4 in).

Bull snakes average weight is 1 to 1,5 kg (2,2 to 3,3 lb.). Heaviest specimen recorded was 4,5 kg (9,9 lb.).