Foster township
- County:
- Hutchinson County
- County Seat:
- No
- Area (mi²):
- 29.299
- State:
- South Dakota
Foster township is located in Hutchinson County, South Dakota. Foster township has a 2026 population of 277. Foster township is currently growing at a rate of 2.59% annually and its population has increased by 3.75% since the most recent census, which recorded a population of 267 in 2020.
The median age in Foster township is 33.5 years: 5.8 years for males, and 87.2 years for females. For every 100 females there are 52.9 males.