Fortine is an unincorporated community and census-designated place (CDP) in Lincoln County, Montana, United States. The population was 325 at the 2010 census.
Fortine is located in northeastern Lincoln County at 48°45′52″N 114°54′11″W (48.764516, -114.902945). U.S. Route 93 passes through the community, leading northwest 11 miles (18 km) to Eureka and southeast 40 miles (64 km) to Whitefish.
According to the United States Census Bureau, the CDP has a total area of 7.1 square miles (18.5 km2), of which 7.1 square miles (18.4 km2) are land and 0.1 square miles (0.2 km2), or 0.99%, are water. The community is in the valley of Fortine Creek, where it is joined by Deep Creek from the east and Murphy Creek from the southeast. Fortine Creek flows northwest to the Tobacco River, a northwest-flowing tributary of the Kootenai River, part of the Columbia River watershed.
Fortine was named for an early settler, Octave Fortine. It was a station on the Great Northern Railway line. The first post office was established in 1905.
As of the census of 2000, there were 169 people, 74 households, and 48 families residing in the CDP. The population density was 56.3 people per square mile (21.8/km²).