Breeds in south-western Canada from south-eastern Alberta, central Saskatchewan and south-western Manitoba, southern in northern USA to north-eastern and north-central Montana (possibly to eastern Wyoming) and north-western South Dakota, perhaps also still north-western Minnesota. Winters in southern USA (south-eastern Arizona, New Mexico and north-central Texas) and northern Mexico (north-eastern Sonora east to western Coahuila, south to Durango and northern Zacatecas).
 
Population
Estimated population is 1,200,000 (2010).
Baird's Sparrow (Centronyx bairdii) [XC574669]
by id from South Golden Valley (near Golva), Golden Valley County, North Dakota, United States (song)
Baird's Sparrow (Centronyx bairdii) [XC335550]
by Thomas Magarian from Bowdoin National Wildlife Refuge, Phillips Co., Montana, United States (song)
Subspecies
No subspecies.
Genus, as currently delimited, is probably polyphyletic. Molecular studies suggest that present species is closely related to Henslow's Sparrow (Passerculus henslowii) in a clade that includes also Melospiza, Passerculus and Xenospiza baileyi.