
Decatur County
- State:
- Indiana
- County Seat:
- Greensburg
Decatur County's estimated 2025 population is 26,289 with a growth rate of -0.21% in the past year according to the most recent United States census data. Decatur County is the 60th largest county in Indiana. The 2010 population was 25,795 and has seen a growth of 1.92% since that time.