Males are slightly larger and more brightly plumaged than females.
While plumage characteristics vary, all Dark-eyed Juncos exhibit a basic plumage form. They are predominately gray above with white or pinkish wash to the undersides, with white outer tail feathers . It breeds from southeastern Montana east through the Black Hills region of South Dakota. It winters at lower elevations in its breeding range south through central Colorado. The head, neck, upper breast, sides, upper flanks, wings, and upperparts are slate gray, while the lower breast, belly, and undertail coverts are white.