Vermillion
- County:
- Marshall County
- County Seat:
- No
- Area (mi²):
- 0.208
- State:
- Kansas
Vermillion is a city located in Marshall County, Kansas. Vermillion has a 2026 population of 76. Vermillion is currently declining at a rate of -2.56% annually and its population has decreased by -2.56% since the most recent census, which recorded a population of 78 in 2020.
The median age in Vermillion is 40 years: 53.5 years for males, and 31.3 years for females. For every 100 females there are 160.0 males.