20 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Athens | 1 | 31,212 | 30,138 | 0.33% | 853 | 37 | Township |
| Athens | 2 | 25,074 | 23,821 | 1.01% | 2,521 | 10 | City |
| York | 3 | 6,836 | 6,840 | 0.4% | 185 | 37 | Township |
| Nelsonville | 4 | 4,543 | 4,600 | -0.26% | 971 | 5 | City |
| Trimble | 5 | 4,055 | 4,065 | 0.4% | 109 | 37 | Township |
| Lee | 6 | 2,857 | 2,844 | 0.49% | 115 | 25 | Township |
| Alexander | 7 | 2,792 | 2,794 | 0.43% | 75 | 37 | Township |
| Glouster | 8 | 1,642 | 1,665 | -0.3% | 1,254 | 1 | Village |
| Canaan | 9 | 1,637 | 1,630 | 0.49% | 43 | 38 | Township |
| Carthage | 10 | 1,490 | 1,490 | 0.54% | 39 | 39 | Township |
| Ames | 11 | 1,230 | 1,232 | 0.33% | 33 | 38 | Township |
| Albany | 12 | 1,014 | 1,003 | 0.2% | 761 | 1 | Village |
| Chauncey | 13 | 949 | 954 | -0.11% | 1,725 | 1 | Village |
| Bern | 14 | 567 | 568 | 0.53% | 18 | 31 | Township |
| Buchtel | 15 | 518 | 522 | -0.19% | 1,102 | 0 | Village |
| Coolville | 16 | 445 | 452 | -0.45% | 454 | 1 | Village |
| Jacksonville | 17 | 396 | 401 | -0.25% | 1,650 | 0 | Village |
| Athens | 18 | 352 | 371 | -1.4% | 14 | 25 | Township |
| Trimble | 19 | 329 | 328 | 0% | 484 | 1 | Village |
| Amesville | 20 | 167 | 171 | -0.6% | 736 | 0 | Village |
Athens is the largest city in Athens County, with a population of 31,212.
Amesville is the smallest city in Athens County, with a population of 167.
There are 20 cities in Athens County, Ohio.