Mount Vernon
- County:
- Davison County
- County Seat:
- No
- Area (mi²):
- 0.34
- State:
- South Dakota
Mount Vernon is a city located in Davison County, South Dakota. Mount Vernon has a 2026 population of 457. Mount Vernon is currently declining at a rate of -0.65% annually and its population has decreased by 0% since the most recent census, which recorded a population of 457 in 2020.