Vermillion township
- County:
- Clay County
- County Seat:
- No
- Area (mi²):
- 22.768
- State:
- South Dakota
Vermillion township is located in Clay County, South Dakota. Vermillion township has a 2026 population of 396. Vermillion township is currently declining at a rate of -1% annually but its population has increased by 3.39% since the most recent census, which recorded a population of 383 in 2020.
The median age in Vermillion township is 52.2 years: 52.5 years for males, and 45.3 years for females. For every 100 females there are 82.0 males.