Ponderosa Pines is a census-designated place (CDP) in Gallatin County, Montana, United States. The population was 336 at the 2010 census. Formerly a 13,000-acre ranch, the land was subdivided into 10- and 20-acre parcels and sold by a Hawaiian real estate agency starting in 1972. The lots lacked water, sewer, electricity and road access, and some were on such steep terrain that building would be impossible.