Mildred is situated along O'Fallon Creek, southeast of Terry. Originally, Mildred was located on the Old Yellowstone Trail with most of the region's social events taking place at the town hall. However, the town's population declined with the drought years and the change of the highway. Mildred, a station for the Milwaukee Railroad, was named for a daughter of a railroad official.
Mildred is located in southeastern area of Montana, southeast of Fallon off I-94.