| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Troy | 1 | 27,530 | 26,393 | 0.68% | 2,179 | 13 | City |
| Piqua | 2 | 21,191 | 20,417 | 0.6% | 1,611 | 13 | City |
| Tipp City | 3 | 10,713 | 10,297 | 0.65% | 1,307 | 8 | City |
| Union | 4 | 7,226 | 6,903 | 0.68% | 851 | 8 | City |
| West Milton | 5 | 4,904 | 4,702 | 0.68% | 1,446 | 3 | Village |
| Covington | 6 | 2,651 | 2,554 | 0.61% | 1,934 | 1 | Village |
| Bradford | 7 | 1,817 | 1,795 | 0.17% | 2,179 | 1 | Village |
| Pleasant Hill | 8 | 1,278 | 1,231 | 0.63% | 2,032 | 1 | Village |
| Fletcher | 9 | 472 | 452 | 0.64% | 1,518 | 0 | Village |
| Laura | 10 | 415 | 397 | 0.73% | 1,549 | 0 | Village |
| Casstown | 11 | 278 | 270 | 0.36% | 2,866 | 0 | Village |
| Potsdam | 12 | 233 | 233 | 0% | 522 | 0 | Village |
| Ludlow Falls | 13 | 179 | 172 | 0.56% | 1,000 | 0 | Village |
| Lockington | 14 | 163 | 154 | -0.61% | 1,940 | 0 | Village |
Troy is the largest city in Miami County, with a population of 27,530.
Lockington is the smallest city in Miami County, with a population of 163.
There are 14 cities in Miami County, Ohio.