Fairfield township
- County:
- Butler County
- County Seat:
- No
- Area (mi²):
- 22.062
- State:
- Ohio
Fairfield township is located in Butler County, Ohio. Fairfield township has a 2026 population of 1,481. Fairfield township is currently declining at a rate of -0.74% annually and its population has decreased by -2.37% since the most recent census, which recorded a population of 1,517 in 2020.
The median household income in Fairfield township is $48,875 with a poverty rate of 19.44%. The median age in Fairfield township is 40.9 years: 39.4 years for males, and 42.1 years for females. For every 100 females there are 144.8 males.