31 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Concord | 1 | 32,446 | 31,486 | 0.61% | 903 | 36 | Township |
| Troy | 2 | 27,163 | 26,375 | 0.59% | 2,211 | 12 | City |
| Piqua | 3 | 20,973 | 20,408 | 0.54% | 1,617 | 13 | City |
| Tipp City | 4 | 10,608 | 10,297 | 0.59% | 1,320 | 8 | City |
| Union | 5 | 9,892 | 9,589 | 0.62% | 209 | 47 | Township |
| Troy | 6 | 7,096 | 7,117 | -0.1% | 320 | 22 | Township |
| Union | 7 | 7,003 | 6,867 | 0.39% | 844 | 8 | City |
| Newberry | 8 | 6,600 | 6,406 | 0.61% | 156 | 42 | Township |
| West Milton | 9 | 4,869 | 4,708 | 0.66% | 1,436 | 3 | Village |
| Troy | 10 | 4,162 | 4,103 | 0.31% | 140 | 30 | Township |
| Newton | 11 | 3,614 | 3,512 | 0.58% | 87 | 42 | Township |
| Troy | 12 | 2,784 | 2,777 | 0% | 111 | 25 | Township |
| Covington | 13 | 2,627 | 2,554 | 0.57% | 1,916 | 1 | Village |
| Staunton | 14 | 2,502 | 2,426 | 0.64% | 96 | 26 | Township |
| Troy | 15 | 2,444 | 2,113 | 2.73% | 105 | 23 | Township |
| Troy | 16 | 2,433 | 2,485 | -0.37% | 67 | 36 | Township |
| Springcreek | 17 | 2,226 | 2,161 | 0.63% | 100 | 22 | Township |
| Bradford | 18 | 1,800 | 1,792 | 0.11% | 2,158 | 1 | Village |
| Elizabeth | 19 | 1,708 | 1,663 | 0.53% | 57 | 30 | Township |
| Lostcreek | 20 | 1,658 | 1,610 | 0.55% | 55 | 30 | Township |
| Brown | 21 | 1,647 | 1,601 | 0.55% | 54 | 30 | Township |
| Washington | 22 | 1,527 | 1,480 | 0.66% | 73 | 21 | Township |
| Pleasant Hill | 23 | 1,271 | 1,235 | 0.55% | 2,021 | 1 | Village |
| Troy | 24 | 1,240 | 1,189 | 1.06% | 87 | 14 | Township |
| Troy | 25 | 1,111 | 1,100 | 0.63% | 66 | 17 | Township |
| Fletcher | 26 | 461 | 453 | 0.44% | 1,482 | 0 | Village |
| Laura | 27 | 415 | 399 | 0.73% | 1,549 | 0 | Village |
| Casstown | 28 | 274 | 266 | 0.74% | 2,825 | 0 | Village |
| Potsdam | 29 | 220 | 224 | -0.45% | 493 | 0 | Village |
| Ludlow Falls | 30 | 178 | 173 | 0.56% | 994 | 0 | Village |
| Lockington | 31 | 155 | 160 | -0.64% | 1,845 | 0 | Village |
Concord is the largest city in Miami County, with a population of 32,446.
Lockington is the smallest city in Miami County, with a population of 155.
There are 31 cities in Miami County, Ohio.