11 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Ashtabula | 1 | 17,675 | 17,975 | -0.28% | 2,294 | 8 | City |
| Conneaut | 2 | 12,383 | 12,304 | 0.11% | 473 | 26 | City |
| Geneva | 3 | 5,846 | 5,921 | -0.2% | 1,463 | 4 | City |
| Jefferson | 4 | 3,173 | 3,218 | -0.22% | 1,273 | 2 | Village |
| North Kingsville | 5 | 2,710 | 2,749 | -0.22% | 303 | 9 | Village |
| Roaming Shores | 6 | 1,565 | 1,582 | -0.19% | 723 | 2 | Village |
| Orwell | 7 | 1,508 | 1,517 | -0.07% | 785 | 2 | Village |
| Andover | 8 | 943 | 957 | -0.21% | 679 | 1 | Village |
| Geneva-on-the-Lake | 9 | 932 | 944 | -0.21% | 390 | 2 | Village |
| North Perry | 10 | 909 | 914 | -0.11% | 234 | 4 | Village |
| Rock Creek | 11 | 660 | 674 | -0.3% | 752 | 1 | Village |
Ashtabula is the largest city in Ashtabula County, with a population of 17,675.
Rock Creek is the smallest city in Ashtabula County, with a population of 660.
There are 11 cities in Ashtabula County, Ohio.