7 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Hillsboro | 1 | 6,674 | 6,448 | 0.57% | 1,219 | 5 | City |
| Greenfield | 2 | 4,354 | 4,342 | 0.05% | 2,087 | 2 | Village |
| Lynchburg | 3 | 1,558 | 1,516 | 0.45% | 1,688 | 1 | Village |
| Leesburg | 4 | 1,287 | 1,274 | 0.16% | 1,102 | 1 | Village |
| Mowrystown | 5 | 386 | 386 | 0% | 801 | 0 | Village |
| Highland | 6 | 232 | 229 | 0.43% | 1,365 | 0 | Village |
| Sinking Spring | 7 | 122 | 121 | 0% | 261 | 0 | Village |
Hillsboro is the largest city in Highland County, with a population of 6,674.
Sinking Spring is the smallest city in Highland County, with a population of 122.
There are 7 cities in Highland County, Ohio.