18 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Peru | 1 | 11,018 | 10,940 | 0.14% | 2,179 | 5 | City |
| Peru | 2 | 10,668 | 10,623 | 0.24% | 426 | 25 | Township |
| Pipe Creek | 3 | 6,675 | 6,742 | 0.57% | 264 | 25 | Township |
| Deer Creek | 4 | 4,714 | 4,707 | 0.28% | 198 | 24 | Township |
| Jefferson | 5 | 2,390 | 2,426 | 0.34% | 74 | 32 | Township |
| Jackson | 6 | 1,781 | 1,821 | 0.28% | 76 | 23 | Township |
| Miami | 7 | 1,297 | 1,306 | -0.46% | 65 | 20 | Township |
| Converse | 8 | 1,118 | 1,153 | -0.62% | 1,130 | 1 | Town |
| Clay | 9 | 854 | 854 | 0.71% | 36 | 24 | Township |
| Perry | 10 | 841 | 848 | 0.72% | 21 | 40 | Township |
| Bunker Hill | 11 | 815 | 817 | -0.12% | 2,095 | 0 | Town |
| Union | 12 | 753 | 769 | 0.4% | 35 | 22 | Township |
| Harrison | 13 | 685 | 688 | 0.74% | 29 | 23 | Township |
| Allen | 14 | 605 | 618 | 0.17% | 28 | 22 | Township |
| Erie | 15 | 532 | 539 | 0.38% | 32 | 17 | Township |
| Denver | 16 | 463 | 476 | -0.64% | 1,929 | 0 | Town |
| Amboy | 17 | 308 | 316 | -0.65% | 917 | 0 | Town |
| Macy | 18 | 192 | 199 | -1.03% | 1,670 | 0 | Town |
Peru is the largest city in Miami County, with a population of 11,018.
Macy is the smallest city in Miami County, with a population of 192.
There are 18 cities in Miami County, Indiana.