27 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Sutton | 1 | 1,439 | 1,451 | -0.14% | 776 | 2 | City |
| Harvard | 2 | 1,072 | 1,090 | -0.65% | 30 | 36 | Township |
| Harvard | 3 | 939 | 947 | -0.11% | 1,456 | 1 | City |
| Clay Center | 4 | 723 | 722 | 0% | 989 | 1 | City |
| Fairfield | 5 | 502 | 511 | -0.99% | 14 | 36 | Township |
| Edgar | 6 | 499 | 502 | -0.4% | 14 | 36 | Township |
| Edgar | 7 | 427 | 426 | 0% | 541 | 1 | City |
| Glenvil | 8 | 387 | 390 | -0.51% | 11 | 36 | Township |
| Fairfield | 9 | 333 | 333 | 0% | 463 | 1 | City |
| Leicester | 10 | 303 | 309 | -0.98% | 9 | 36 | Township |
| Glenvil | 11 | 269 | 266 | 0.37% | 1,555 | 0 | Village |
| Trumbull | 12 | 198 | 197 | 0% | 459 | 0 | Village |
| Spring Ranch | 13 | 153 | 150 | 0.66% | 4 | 36 | Township |
| School Creek | 14 | 144 | 141 | 0.7% | 4 | 35 | Township |
| Lewis | 15 | 135 | 129 | 1.5% | 4 | 36 | Township |
| Sutton | 16 | 116 | 119 | -0.85% | 3 | 34 | Township |
| Logan | 17 | 106 | 107 | -0.93% | 3 | 36 | Township |
| Inland | 18 | 97 | 100 | -1.02% | 3 | 36 | Township |
| Eldorado | 19 | 93 | 96 | -1.06% | 3 | 36 | Township |
| Lone Tree | 20 | 89 | 92 | -1.11% | 3 | 35 | Township |
| Sheridan | 21 | 77 | 77 | 0% | 2 | 36 | Township |
| Lynn | 22 | 70 | 70 | 0% | 2 | 35 | Township |
| Marshall | 23 | 54 | 54 | 0% | 2 | 36 | Township |
| Ong | 24 | 51 | 50 | 0% | 178 | 0 | Village |
| Deweese | 25 | 44 | 44 | 0% | 349 | 0 | Village |
| Saronville | 26 | 37 | 37 | 0% | 248 | 0 | Village |
| Stockham | 27 | 34 | 33 | 0% | 201 | 0 | Village |
Sutton is the largest city in Clay County, with a population of 1,439.
Stockham is the smallest city in Clay County, with a population of 34.
There are 27 cities in Clay County, Nebraska.