Mammoth is an unincorporated community and census-designated place (CDP) in Madison County, Montana, United States.

It is in the northern part of the county, in the valley of the South Boulder River within the northern end of the Tobacco Root Mountains.

Mammoth is reached by South Boulder Road, which leads north 11 miles (18 km) to Montana Highway 359 at a point 5 miles (8 km) south of Cardwell.

Mammoth was first listed as a CDP prior to the 2020 census,[2] when it had a population of 4.

This Madison County, Montana state location article is a stub.