19 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Fishers | 1 | 105,107 | 99,502 | 1.08% | 2,915 | 36 | City |
| Carmel | 2 | 104,530 | 99,907 | 0.89% | 2,130 | 49 | City |
| Clay | 3 | 103,936 | 99,241 | 0.99% | 2,116 | 49 | Township |
| Noblesville | 4 | 76,508 | 70,163 | 1.69% | 2,197 | 35 | City |
| Fall Creek | 5 | 74,364 | 71,210 | -0.27% | 2,206 | 34 | Township |
| Noblesville | 6 | 69,340 | 64,343 | 1.3% | 1,481 | 47 | Township |
| Westfield | 7 | 66,986 | 47,025 | 6.34% | 2,054 | 33 | City |
| Delaware | 8 | 36,389 | 34,878 | -0.25% | 2,390 | 15 | Township |
| McCordsville | 9 | 12,458 | 8,888 | 6.08% | 1,502 | 8 | Town |
| Wayne | 10 | 11,660 | 10,969 | 1.05% | 332 | 35 | Township |
| Jackson | 11 | 11,226 | 10,883 | -0.76% | 205 | 55 | Township |
| Cicero | 12 | 8,076 | 8,081 | 0.21% | 120 | 68 | Township |
| Cicero | 13 | 5,678 | 5,321 | 1.27% | 3,486 | 2 | Town |
| Adams | 14 | 5,605 | 5,217 | 1.67% | 116 | 48 | Township |
| Sheridan | 15 | 3,581 | 3,111 | 2.7% | 1,422 | 3 | Town |
| White River | 16 | 2,323 | 2,429 | -0.94% | 42 | 56 | Township |
| Arcadia | 17 | 1,451 | 1,513 | -0.89% | 2,633 | 1 | Town |
| Atlanta | 18 | 741 | 721 | 0.54% | 2,367 | 0 | Town |
| Williams Creek | 19 | 429 | 428 | 0% | 1,292 | 0 | Town |
Fishers is the largest city in Hamilton County, with a population of 105,107.
Williams Creek is the smallest city in Hamilton County, with a population of 429.
There are 19 cities in Hamilton County, Indiana.