| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Kenton | 1 | 7,783 | 7,957 | -0.32% | 1,557 | 5 | City |
| Ada | 2 | 4,938 | 5,328 | -0.94% | 2,314 | 2 | Village |
| Forest | 3 | 1,326 | 1,355 | -0.45% | 793 | 2 | Village |
| Alger | 4 | 823 | 843 | -0.48% | 2,780 | 0 | Village |
| Dunkirk | 5 | 749 | 772 | -0.53% | 1,138 | 1 | Village |
| Mount Victory | 6 | 592 | 605 | -0.5% | 701 | 1 | Village |
| Ridgeway | 7 | 310 | 316 | -0.64% | 548 | 1 | Village |
Kenton is the largest city in Hardin County, with a population of 7,783.
Ridgeway is the smallest city in Hardin County, with a population of 310.
There are 7 cities in Hardin County, Ohio.