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 738 at the 2010 census. It is part of the Great Falls, Montana Metropolitan Statistical Area. The Zip Code is 59485.

Cascade County is a county located in the U.S. state of Montana. As of the 2020 census, the population was 84,414, making it the fifth-most populous county in Montana. Its county seat is Great Falls.