23 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Newton | 1 | 18,256 | 18,573 | -0.35% | 1,233 | 15 | City |
| Emma | 2 | 4,046 | 4,053 | 0% | 112 | 36 | Township |
| Hesston | 3 | 3,478 | 3,498 | -0.11% | 976 | 4 | City |
| Newton | 4 | 2,210 | 2,233 | -0.05% | 97 | 23 | Township |
| Halstead | 5 | 2,136 | 2,174 | -0.37% | 1,449 | 1 | City |
| North Newton | 6 | 1,793 | 1,816 | -0.28% | 1,966 | 1 | City |
| Sedgwick | 7 | 1,730 | 1,752 | -0.12% | 48 | 36 | Township |
| Sedgwick | 8 | 1,577 | 1,599 | -0.32% | 965 | 2 | City |
| Burrton | 9 | 1,024 | 1,041 | 0% | 28 | 36 | Township |
| Burrton | 10 | 841 | 863 | -0.59% | 948 | 1 | City |
| Walton | 11 | 690 | 711 | -0.58% | 22 | 32 | Township |
| Darlington | 12 | 543 | 547 | 0.18% | 15 | 35 | Township |
| Macon | 13 | 499 | 493 | 0.81% | 15 | 34 | Township |
| Walton | 14 | 476 | 482 | 0% | 13 | 37 | Township |
| Pleasant | 15 | 441 | 438 | 0.46% | 12 | 36 | Township |
| Halstead | 16 | 416 | 414 | 0.24% | 12 | 35 | Township |
| Richland | 17 | 379 | 380 | -0.26% | 10 | 36 | Township |
| Walton | 18 | 313 | 308 | 0% | 6 | 54 | Township |
| Garden | 19 | 293 | 290 | 0.69% | 8 | 36 | Township |
| Alta | 20 | 230 | 230 | 0% | 6 | 36 | Township |
| Walton | 21 | 216 | 223 | -0.92% | 695 | 0 | City |
| Lake | 22 | 162 | 159 | 1.25% | 5 | 36 | Township |
| Furley | 23 | 62 | 25 | 6.9% | 251 | 0 | CDP |
Newton is the largest city in Harvey County, with a population of 18,256.
Furley is the smallest city in Harvey County, with a population of 62.
There are 23 cities in Harvey County, Kansas.