7 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Kenton | 1 | 7,808 | 7,954 | -0.31% | 1,562 | 5 | City |
| Ada | 2 | 5,275 | 5,329 | -0.17% | 2,472 | 2 | Village |
| Forest | 3 | 1,320 | 1,355 | -0.45% | 789 | 2 | Village |
| Alger | 4 | 820 | 843 | -0.49% | 2,770 | 0 | Village |
| Dunkirk | 5 | 748 | 772 | -0.53% | 1,137 | 1 | Village |
| Mount Victory | 6 | 589 | 607 | -0.51% | 698 | 1 | Village |
| Ridgeway | 7 | 311 | 317 | -0.32% | 549 | 1 | Village |
Kenton is the largest city in Hardin County, with a population of 7,808.
Ridgeway is the smallest city in Hardin County, with a population of 311.
There are 7 cities in Hardin County, Ohio.