Sumner township
- County:
- Spink County
- County Seat:
- No
- Area (mi²):
- 36.091
- State:
- South Dakota
Sumner township is located in Spink County, South Dakota. Sumner township has a 2026 population of 13. Sumner township is currently declining at a rate of 0% annually and its population has decreased by -7.14% since the most recent census, which recorded a population of 14 in 2020.
The median age in Sumner township is 60.5 years: 65.5 years for males, and 58.5 years for females. For every 100 females there are 50.0 males.