The Canadian Toad is a medium sized toad attaining lengths around 3 inches. The color of these can be variable, ranging from brown to green and sometimes even reddish. Its warts are brown or reddish. The most distinctive feature of this species is its interorbital cranial ridges or crests. These unite to form a unique raised "boss" (prominent bump) between the eyes. This is also the case with the Great Plains Toad, but in this species the crests unite on the snout.

Often times the parotid glands on Canadian Toads may be hard to discern due to indistinct boundaries, particularly on dark individuals most commonly seen during the spring breeding season. The ventral surface of the Canadian Toad is often spotted against a light background. The Canadian Toad is one of the few species of amphibians with a predominantly Canadian distribution.
 
The Wyoming Toad, B. baxteri (not shown), was previously considered a subspecies of the Canadian Toad (B. h. baxteri). This species, found along the Laramie and Big Rivers, is federally listed as endangered. The Wyoming Toad looks very silmilar to the Canadian Toad except in that it has a narrower middorsal stripe.