| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Sutton | 1 | 1,464 | 1,449 | -0.14% | 790 | 2 | City |
| Harvard | 2 | 951 | 946 | -0.11% | 1,474 | 1 | City |
| Clay Center | 3 | 731 | 722 | 0.14% | 1,000 | 1 | City |
| Edgar | 4 | 431 | 426 | 0% | 546 | 1 | City |
| Fairfield | 5 | 337 | 332 | 0% | 469 | 1 | City |
| Glenvil | 6 | 269 | 266 | 0% | 1,555 | 0 | Village |
| Trumbull | 7 | 200 | 197 | 0% | 464 | 0 | Village |
| Ong | 8 | 49 | 49 | 0% | 171 | 0 | Village |
| Deweese | 9 | 43 | 43 | 0% | 341 | 0 | Village |
| Saronville | 10 | 37 | 37 | 0% | 248 | 0 | Village |
| Stockham | 11 | 34 | 33 | 0% | 201 | 0 | Village |
Sutton is the largest city in Clay County, with a population of 1,464.
Stockham is the smallest city in Clay County, with a population of 34.
There are 11 cities in Clay County, Nebraska.