| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Columbus | 1 | 944,402 | 906,675 | 0.64% | 4,255 | 222 | City |
| Dublin | 2 | 49,075 | 49,335 | -0.04% | 1,988 | 25 | City |
| Grove City | 3 | 45,821 | 41,320 | 1.42% | 2,420 | 19 | City |
| Reynoldsburg | 4 | 43,780 | 41,052 | 0.99% | 3,865 | 11 | City |
| Hilliard | 5 | 39,270 | 37,177 | 0.96% | 2,751 | 14 | City |
| Gahanna | 6 | 35,937 | 35,701 | -0.14% | 2,891 | 12 | City |
| Upper Arlington | 7 | 35,721 | 36,746 | -0.48% | 3,647 | 10 | City |
| Whitehall | 8 | 19,753 | 20,104 | -0.26% | 3,743 | 5 | City |
| Worthington | 9 | 14,501 | 14,781 | -0.29% | 2,651 | 5 | City |
| Bexley | 10 | 12,167 | 13,909 | -2.29% | 5,026 | 2 | City |
| New Albany | 11 | 11,937 | 11,184 | 1.14% | 549 | 22 | City |
| Canal Winchester | 12 | 10,255 | 9,191 | 1.96% | 1,262 | 8 | City |
| Grandview Heights | 13 | 9,341 | 8,249 | 2.51% | 7,103 | 1 | City |
| Obetz | 14 | 7,779 | 5,523 | 5.95% | 1,335 | 6 | Village |
| Groveport | 15 | 5,780 | 6,002 | -0.65% | 664 | 9 | City |
| Urbancrest | 16 | 997 | 1,034 | -0.6% | 1,698 | 1 | Village |
| Marble Cliff | 17 | 660 | 651 | 0.3% | 2,349 | 0 | Village |
| Valleyview | 18 | 636 | 658 | -0.63% | 4,448 | 0 | Village |
| Riverlea | 19 | 574 | 596 | -0.69% | 3,801 | 0 | Village |
| Harrisburg | 20 | 312 | 314 | -0.32% | 2,013 | 0 | Village |
| Lockbourne | 21 | 226 | 237 | -0.88% | 288 | 1 | Village |
| Brice | 22 | 111 | 94 | 0.91% | 1,261 | 0 | Village |
Columbus is the largest city in Franklin County, with a population of 944,402.
Brice is the smallest city in Franklin County, with a population of 111.
There are 22 cities in Franklin County, Ohio.