In the United States, the Varied Bunting is found only along the border with Mexico; southeast Arizona, extreme southwest & southeast New Mexico and along the Rio Grande River in Texas. In southeast Arizona, Varied Buntings are locally fairly common summer residents inhabiting mesquite thickets of foothill canyons and washes, frequently associated with Ocotillo cactus. Because their breeding is timed with the summer monsoons, they are late arrivers to breeding areas. Male Varied Buntings casually begin singing and setting up territories upon their arrival. During the dry period prior to the summer rains, Varied Buntings can be found utilizing communal water sources (i.e. cattle tanks, persistent pools along ephemeral creeks) without territorial interactions. As with other monsoon breeders the intensity of the males singing and defense of territories increases as the raining season approaches.

Areas in southeast Arizona where bird watchers frequently find Varied Bunting include: foothills around the base of the Santa Rita Mountains (specifically Florida, Madera, Chino, and Montosa Canyons), along Sonoita Creek in the Patagonia area, mesquite thickets along the Santa Cruz River near Tubac & Tumacacori, and the canyons of the Atascosa Highlands (Sycamore Canyon and California Gulch).

The adult male Varied Bunting often appears very dark, almost black, in the shade or other poor lighting conditions; however the red, blue, and purple plumage is unmistakable in good light. Both the common and scientific names are accurate in describing the males of this species. The female Varied Bunting, as well as second year males, appears similar to other Passerina females though are more uniform brownish, have a curved culmen, and short wings. The second year male Varied Bunting may be separated from females by a tinge of purple or red in the body plumage, particularly the upper tail coverts (not typically visible in the field, but useful when handled birds for banding). Perhaps an easier way to distinguish a second year male Varied Bunting is when a female looking Varied Bunting is singing and defending territory.