Ballantine is a census-designated place (CDP) in Yellowstone County, Montana, United States. It lies approximately nine miles (10 km) northeast of Billings on Interstate 94. The population was 346 at the 2000 census. Ballantine, along with the communities of Pompey's Pillar, Worden, and Huntley, is part of the Huntley Project, an irrigation district created by the United States Bureau of Reclamation. The majority of Ballantine's population lives on scattered farms and ranches surrounding the actual townsite.
Ballantine was founded on land that had been part of the Crow Indian Reservation. In 1896, the Burlington & Missouri River Railroad established Ballantine as a station, named for homesteader E. P. Ballantine. By 1907 the town had a post office and the Chicago, Burlington & Quincy Railroad had taken over rail operations.
It was in 1907 that Ballantine became part of a federally funded irrigation district, the Huntley Project. Irrigation slowly changed the sagebrush landscape into farms growing sugar beets, alfalfa, and other crops. The population grew slowly and included many European immigrants.