
Vermillion
- County:
- Clay County
- County Seat:
- No
- Area (mi²):
- 4.661
- State:
- South Dakota
Vermillion is a city located in Clay County, South Dakota. Vermillion has a 2025 population of 12,205. Vermillion is currently growing at a rate of 0.8% annually and its population has increased by 4.14% since the most recent census, which recorded a population of 11,720 in 2020.
The average household income in Vermillion is $63,858 with a poverty rate of 25.1%. The median age in Vermillion is 22.9 years: 23.4 years for males, and 22.6 years for females.