Males and females have yellow eyes year-round, similar to Common Grackle and male Brewer's Blackbirds. Brewer's Blackbird, however, has longer legs and longer tail. In fall and winter, male Brewer's Blackbird shows less rusty feather edging. Breeding male Brewer's Blackbird is glossier, with a purplish cast on the head and breast, contrasting with a green cast on back and wings. Female Brewer's Blackbird has dark eyes and is brownish gray rather than slate-gray. Beware, female Brewer's occasionally have pale eyes. Brewer's Blackbirds also favors open areas, agricultural lands and suburban areas, while Rusty Blackbirds prefer wooded swamps.
Common Grackle is larger overall with a thicker bill and a longer, wedge-shaped tail. Rusty Blackbirds have a square-tipped tail and are more slender overall.
Red-winged Blackbird and Brown-headed Cowbird are more compact. They have dark eyes, shorter and stouter bills, and shorter tails.