Prairie County, Montana

Prairie County
Downtown Terry, Montana during a typical snowy day.
Location within the U.S. state of Montana
Montana's location within the U.S.
Coordinates: 46°51′N 105°22′W / 46.85°N 105.37°W / 46.85; -105.37
Country United States
State Montana
FoundedFebruary 5, 1915
Named afterPrairie landscape
SeatTerry
Largest townTerry
Area
  Total
1,743 sq mi (4,510 km2)
  Land1,737 sq mi (4,500 km2)
  Water5.8 sq mi (15 km2)  0.3%
Population
 (2020)
  Total
1,088
  Estimate 
(2024)
1,112
  Density0.6/sq mi (0.2/km2)
Time zoneUTC−7 (Mountain)
  Summer (DST)UTC−6 (MDT)
Congressional district2nd
Websitevisitterrymt.com (Terry Chamber of Commerce)
  • Montana county number 45

Prairie County is a county in the U.S. state of Montana. As of the 2020 census, the population was 1,088, making it the fifth-least populous county in Montana. Its county seat is Terry. Prairie County was created by the Montana Legislature in 1915 out of parts of Custer, Dawson, and Fallon Counties. The name was selected in a contest and reflects the predominant landscape of the region.

The county was the site of the 1938 Custer Creek train wreck that killed 47 people and injured 75.