Ballantine is a census-designated place in Yellowstone County, Montana, United States. It lies approximately nine miles 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.