
Plainfield township
- County:
- Brule County
- County Seat:
- No
- Area (mi²):
- 35.472
- State:
- South Dakota
Plainfield township is located in Brule County, South Dakota. Plainfield township has a 2025 population of 36. Plainfield township is currently declining at a rate of 0% annually and its population has decreased by 0% since the most recent census, which recorded a population of 36 in 2020.
The average household income in Plainfield township is $71,200 with a poverty rate of 0%. The median age in Plainfield township is 45.5 years: 38.5 years for males, and 45.5 years for females.