Founded in February 5, 1915, Prairie County is one of 56 counties in the state of Montana. Historically, Prairie County was formed from Dawson County and Fallon County. The city of Terry is the county seat. With FIPS code of 79, Prairie County has a population of 1,091 and area of 1,737 square miles (4,499 km2).
List of all cities in Prairie County, MT alphabetically
| City/Town | Postal Code | Area Code |
| Fallon, MT | 59326 | 406 |
| 59341 | 406 | |
| Mildred, MT | 59341 | 406 |
| Terry, MT | 59349 | 406 |