17 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| London | 1 | 10,861 | 10,270 | 1.1% | 1,293 | 8 | City |
| Union | 2 | 5,624 | 5,871 | 0.11% | 145 | 39 | Township |
| West Jefferson | 3 | 5,140 | 4,155 | 3.99% | 518 | 10 | Village |
| Darby | 4 | 4,514 | 4,264 | 0.74% | 213 | 21 | Township |
| Plain City | 5 | 4,429 | 4,151 | 1.26% | 1,611 | 3 | Village |
| Pleasant | 6 | 3,453 | 3,261 | 1.32% | 111 | 31 | Township |
| Somerford | 7 | 3,132 | 3,059 | 0.8% | 103 | 30 | Township |
| Canaan | 8 | 2,749 | 2,663 | 0.92% | 79 | 35 | Township |
| Mount Sterling | 9 | 2,102 | 1,941 | 1.55% | 1,245 | 2 | Village |
| Range | 10 | 987 | 969 | 0.71% | 21 | 48 | Township |
| Deer Creek | 11 | 932 | 918 | 0.43% | 30 | 31 | Township |
| Stokes | 12 | 655 | 645 | 0.61% | 19 | 35 | Township |
| Paint | 13 | 575 | 564 | 0.7% | 15 | 37 | Township |
| Pike | 14 | 571 | 541 | 0.88% | 22 | 26 | Township |
| Oak Run | 15 | 531 | 515 | 1.34% | 19 | 28 | Township |
| South Solon | 16 | 330 | 327 | 0% | 1,404 | 0 | Village |
| Midway | 17 | 273 | 270 | 0% | 1,050 | 0 | Village |
London is the largest city in Madison County, with a population of 10,861.
Midway is the smallest city in Madison County, with a population of 273.
There are 17 cities in Madison County, Ohio.