20 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Peru | 1 | 10,963 | 10,937 | 0.05% | 2,168 | 5.06 | City |
| Peru township | 2 | 10,823 | 10,622 | 1.06% | 433 | 25.01 | Township |
| Pipe Creek township | 3 | 6,386 | 6,745 | -1.5% | 252 | 25.33 | Township |
| Deer Creek township | 4 | 4,660 | 4,707 | -0.32% | 196 | 23.76 | Township |
| Jefferson township | 5 | 2,284 | 2,420 | -1.59% | 71 | 32.18 | Township |
| Grissom AFB | 6 | 1,890 | 2,368 | -11.39% | 473 | 4 | CDP |
| Jackson township | 7 | 1,707 | 1,818 | -1.67% | 73 | 23.30 | Township |
| Miami township | 8 | 1,322 | 1,310 | 0.46% | 67 | 19.87 | Township |
| Mexico | 9 | 1,201 | 1,283 | 2.04% | 219 | 5.49 | CDP |
| Converse | 10 | 1,093 | 1,152 | -1.09% | 1,105 | 0.99 | Town |
| Clay township | 11 | 815 | 851 | -1.33% | 34 | 23.89 | Township |
| Perry township | 12 | 801 | 848 | -1.6% | 20 | 40.39 | Township |
| Bunker Hill | 13 | 788 | 818 | -0.76% | 2,026 | 0.39 | Town |
| Union township | 14 | 725 | 771 | -1.63% | 33 | 21.73 | Township |
| Harrison township | 15 | 650 | 689 | -1.52% | 28 | 23.38 | Township |
| Allen township | 16 | 584 | 619 | -1.52% | 27 | 21.51 | Township |
| Erie township | 17 | 517 | 540 | -1.15% | 31 | 16.68 | Township |
| Denver | 18 | 454 | 476 | -0.87% | 1,892 | 0.24 | Town |
| Amboy | 19 | 302 | 316 | -0.98% | 899 | 0.34 | Town |
| Macy | 20 | 192 | 202 | -1.03% | 1,670 | 0.12 | Town |
Peru is the largest city in Miami County, with a population of 10,963.
Macy is the smallest city in Miami County.
There are 20 cities in Miami County, Indiana.