34 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Springfield | 1 | 58,025 | 58,590 | -0.19% | 2,178 | 27 | City |
| Springfield | 2 | 36,012 | 35,776 | 0.62% | 2,211 | 16 | Township |
| Springfield | 3 | 27,159 | 27,014 | 0.2% | 1,262 | 22 | Township |
| Springfield | 4 | 14,206 | 14,160 | 0.26% | 972 | 15 | Township |
| Moorefield | 5 | 12,583 | 12,633 | 0.21% | 421 | 30 | Township |
| Springfield | 6 | 12,253 | 12,326 | 0.16% | 404 | 30 | Township |
| Springfield | 7 | 11,064 | 11,101 | -0.09% | 302 | 37 | Township |
| Mad River | 8 | 10,945 | 10,991 | 0.2% | 330 | 33 | Township |
| German | 9 | 7,577 | 7,578 | 0.26% | 229 | 33 | Township |
| Springfield | 10 | 6,747 | 6,777 | 0% | 202 | 33 | Township |
| New Carlisle | 11 | 5,499 | 5,559 | -0.22% | 2,050 | 3 | City |
| Springfield | 12 | 5,459 | 5,481 | -0.13% | 294 | 19 | Township |
| Park Layne | 13 | 3,882 | 4,420 | -0.77% | 2,652 | 1 | CDP |
| Pike | 14 | 3,727 | 3,733 | 0.24% | 100 | 37 | Township |
| Harmony | 15 | 3,626 | 3,639 | 0.19% | 72 | 51 | Township |
| Springfield | 16 | 3,406 | 3,453 | -0.29% | 93 | 37 | Township |
| Pleasant | 17 | 3,128 | 3,127 | 0.26% | 75 | 42 | Township |
| Springfield | 18 | 2,991 | 3,034 | -0.13% | 83 | 36 | Township |
| Springfield | 19 | 2,550 | 2,609 | -0.58% | 84 | 30 | Township |
| Enon | 20 | 2,443 | 2,466 | -0.2% | 1,888 | 1 | Village |
| Choctaw Lake | 21 | 2,339 | 2,099 | 2.32% | 2,256 | 1 | CDP |
| Green Meadows | 22 | 2,157 | 2,060 | -0.51% | 2,713 | 1 | CDP |
| Springfield | 23 | 1,948 | 2,005 | -0.31% | 63 | 31 | Township |
| South Charleston | 24 | 1,691 | 1,709 | -0.24% | 1,371 | 1 | Village |
| Crystal Lakes | 25 | 1,636 | 1,478 | 0.68% | 3,401 | 0 | CDP |
| Holiday Valley | 26 | 1,516 | 1,573 | 0% | 833 | 2 | CDP |
| Wright-Patterson AFB | 27 | 1,487 | 2,414 | -1.52% | 151 | 10 | CDP |
| Medway | 28 | 668 | 360 | 7.22% | 1,400 | 0 | CDP |
| North Hampton | 29 | 450 | 457 | -0.44% | 1,169 | 0 | Village |
| South Vienna | 30 | 406 | 411 | -0.25% | 624 | 1 | Village |
| Tremont City | 31 | 344 | 352 | -0.58% | 1,557 | 0 | Village |
| Plumwood | 32 | 268 | 240 | -1.11% | 431 | 1 | CDP |
| Donnelsville | 33 | 256 | 260 | -0.39% | 805 | 0 | Village |
| Catawba | 34 | 241 | 245 | -0.41% | 1,043 | 0 | Village |
Springfield is the largest city in Clark County, with a population of 58,025.
Catawba is the smallest city in Clark County, with a population of 241.
There are 34 cities in Clark County, Ohio.