| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| West Union | 1 | 3,108 | 3,003 | 0.55% | 1,098 | 3 | Village |
| Manchester | 2 | 1,878 | 1,843 | 0.21% | 1,482 | 1 | Village |
| Peebles | 3 | 1,775 | 1,773 | -0.11% | 1,462 | 1 | Village |
| Winchester | 4 | 1,000 | 979 | 0.2% | 382 | 3 | Village |
| Seaman | 5 | 988 | 972 | 0% | 926 | 1 | Village |
West Union is the largest city in Adams County, with a population of 3,108.
Seaman is the smallest city in Adams County, with a population of 988.
There are 5 cities in Adams County, Ohio.