Vandalia
- County:
- Audrain County
- County Seat:
- No
- Area (mi²):
- 2.244
- State:
- Missouri
Vandalia is a city located in Audrain County, Missouri. Vandalia has a 2026 population of 2,939. Vandalia is currently declining at a rate of -0.07% annually and its population has decreased by -14.06% since the most recent census, which recorded a population of 3,420 in 2020.