15 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Zionsville | 1 | 34,323 | 30,837 | 1.72% | 511 | 67 | Town |
| Center | 2 | 20,471 | 18,841 | 1.76% | 313 | 65 | Township |
| Lebanon | 3 | 18,054 | 16,716 | 1.25% | 845 | 21 | City |
| Whitestown | 4 | 16,671 | 10,350 | 6.75% | 1,050 | 16 | Town |
| Worth | 5 | 7,427 | 4,494 | 9% | 483 | 15 | Township |
| Jamestown | 6 | 3,285 | 3,226 | 0.09% | 159 | 21 | Township |
| Jackson | 7 | 2,871 | 2,746 | 1.2% | 60 | 48 | Township |
| Sugar Creek | 8 | 2,215 | 2,165 | 0.91% | 66 | 34 | Township |
| Jefferson | 9 | 1,552 | 1,490 | 1.11% | 33 | 46 | Township |
| Thorntown | 10 | 1,427 | 1,429 | 0% | 2,018 | 1 | Town |
| Perry | 11 | 1,336 | 828 | 8.62% | 186 | 7 | Township |
| Jamestown | 12 | 975 | 941 | 0.62% | 930 | 1 | Town |
| Harrison | 13 | 741 | 715 | 0.95% | 30 | 24 | Township |
| Advance | 14 | 517 | 502 | 0.58% | 878 | 1 | Town |
| Ulen | 15 | 116 | 113 | 0.87% | 509 | 0 | Town |
Zionsville is the largest city in Boone County, with a population of 34,323.
Ulen is the smallest city in Boone County, with a population of 116.
There are 15 cities in Boone County, Indiana.