Ulm is a census-designated place (CDP) in Cascade County, Montana, United States. It was originally a large ranch owned by Indiana-born cattleman William Ulm. The population was 750 at the 2000 census. It is part of the 'Great Falls, Montana Metropolitan Statistical Area'.
Ulm is located at 47°25′43″N 111°30′36″W / 47.42861°N 111.51°W / 47.42861; -111.51 (47.428684, -111.510044).
According to the United States Census Bureau, the CDP has a total area of 20.8 square miles (53.8 km²), of which, 20.1 square miles (52.0 km²) of it is land and 0.7 square miles (1.8 km²) of it (3.42%) is water.