While borophagine canids are known from numerous Tertiary faunas across North America, they have not been well documented from the Tertiary faunas of Idaho. Five species represented by 2 genera are now known from Idaho faunas ranging from the latest Clarendonian / earliest Hemphillian to the late Blancan. The earliest records of borophagines in Idaho are Epicyon haydeni from the early Hemphillian Star Valley fauna and Borophagus pugnator from the late Clarendonian / early Hemphillian Poison Creek Formation. Borophagus secundus is present in the late Hemphillian Chalk Hills Formation, and 2 species are present in the Blancan Glenns Ferry Formation: (1) B. hilli in the early Blancan Hagerman local fauna and (2) the terminal taxon of the subfamily, B. diversidens, in the late Blancan Grand View local fauna.