8 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Mexico | 1 | 11,504 | 11,438 | 0.1% | 945 | 12 | City |
| Vandalia | 2 | 2,698 | 3,420 | -4.26% | 1,202 | 2 | City |
| Laddonia | 3 | 510 | 501 | 0.39% | 723 | 1 | City |
| Martinsburg | 4 | 260 | 251 | 0.78% | 952 | 0 | Town |
| Farber | 5 | 252 | 255 | 0% | 881 | 0 | City |
| Benton City | 6 | 102 | 104 | 0% | 981 | 0 | Village |
| Rush Hill | 7 | 97 | 99 | 0% | 539 | 0 | Village |
| Vandiver | 8 | 63 | 63 | 0% | 202 | 0 | Village |
Mexico is the largest city in Audrain County, with a population of 11,504.
Vandiver is the smallest city in Audrain County, with a population of 63.
There are 8 cities in Audrain County, Missouri.