20 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Sycamore | 1 | 19,730 | 19,573 | 0.63% | 2,933 | 7 | Township |
| Crane | 2 | 7,441 | 7,553 | -0.31% | 190 | 39 | Township |
| Upper Sandusky | 3 | 6,611 | 6,689 | -0.24% | 979 | 7 | City |
| Crawford | 4 | 4,515 | 4,623 | -0.15% | 125 | 36 | Township |
| Carey | 5 | 3,472 | 3,559 | -0.52% | 1,608 | 2 | Village |
| Sycamore | 6 | 1,424 | 1,471 | -0.35% | 59 | 24 | Township |
| Antrim | 7 | 1,118 | 1,156 | -0.62% | 35 | 32 | Township |
| Tymochtee | 8 | 1,058 | 1,092 | -0.38% | 29 | 36 | Township |
| Eden | 9 | 979 | 1,007 | -0.41% | 32 | 30 | Township |
| Pitt | 10 | 874 | 908 | -0.46% | 22 | 39 | Township |
| Richland | 11 | 811 | 847 | -0.73% | 27 | 30 | Township |
| Sycamore | 12 | 761 | 794 | -0.91% | 1,195 | 1 | Village |
| Mifflin | 13 | 744 | 768 | -0.4% | 20 | 36 | Township |
| Nevada | 14 | 685 | 704 | -0.58% | 668 | 1 | Village |
| Ridge | 15 | 494 | 509 | -0.4% | 33 | 15 | Township |
| Marseilles | 16 | 367 | 382 | -0.27% | 15 | 24 | Township |
| Wharton | 17 | 312 | 327 | -0.95% | 248 | 1 | Village |
| Harpster | 18 | 154 | 161 | -1.28% | 78 | 2 | Village |
| Kirby | 19 | 113 | 118 | -0.88% | 1,046 | 0 | Village |
| Marseilles | 20 | 93 | 97 | -1.06% | 949 | 0 | Village |
Sycamore is the largest city in Wyandot County, with a population of 19,730.
Marseilles is the smallest city in Wyandot County, with a population of 93.
There are 20 cities in Wyandot County, Ohio.