Ballantine is a census-designated place (CDP) in Yellowstone County, Montana. Its population at the 2000 census was 346.
Along with the communities of Pompey's Pillar, Worden, and Huntley, Ballantine is part of the Huntley Project, an irrigation district created by the United States Bureau of Reclamation. The residents have farmlands and ranches surrounding the CDP limits.
The population predominantly comprises White Americans. A significant percentage of the population comprises people of Hispanic origin, as well as a small percentage of Native Americans.