33 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Trotwood | 1 | 23,071 | 23,079 | -0.01% | 757 | 30 | City |
| Greenville | 2 | 17,053 | 17,185 | 0.05% | 298 | 57 | Township |
| Greenville | 3 | 12,675 | 12,805 | -0.2% | 1,905 | 7 | City |
| Twin | 4 | 4,199 | 4,239 | 0.02% | 145 | 29 | Township |
| Adams | 5 | 3,314 | 3,345 | 0.06% | 89 | 37 | Township |
| Versailles | 6 | 2,712 | 2,746 | -0.26% | 1,351 | 2 | Village |
| Arcanum | 7 | 2,327 | 2,356 | -0.26% | 1,829 | 1 | Village |
| Neave | 8 | 2,196 | 2,197 | 0.27% | 96 | 23 | Township |
| Brown | 9 | 2,035 | 2,046 | 0.1% | 69 | 30 | Township |
| Union City | 10 | 1,560 | 1,578 | -0.26% | 1,699 | 1 | Village |
| Patterson | 11 | 1,419 | 1,434 | 0.07% | 53 | 27 | Township |
| Washington | 12 | 1,266 | 1,277 | 0% | 40 | 32 | Township |
| Ansonia | 13 | 1,147 | 1,156 | -0.17% | 1,773 | 1 | Village |
| Allen | 14 | 1,002 | 1,005 | 0.1% | 35 | 29 | Township |
| Liberty | 15 | 980 | 988 | 0.1% | 30 | 33 | Township |
| Wabash | 16 | 919 | 928 | 0% | 42 | 22 | Township |
| New Madison | 17 | 832 | 842 | -0.24% | 1,755 | 0 | Village |
| Richland | 18 | 829 | 832 | 0% | 39 | 21 | Township |
| Mississinawa | 19 | 684 | 686 | 0.15% | 23 | 29 | Township |
| Wayne Lakes | 20 | 683 | 688 | -0.15% | 1,286 | 1 | Village |
| York | 21 | 557 | 564 | 0% | 26 | 22 | Township |
| Gettysburg | 22 | 461 | 465 | -0.22% | 1,053 | 0 | Village |
| Pitsburg | 23 | 375 | 382 | -0.53% | 2,219 | 0 | Village |
| Osgood | 24 | 298 | 306 | -0.67% | 847 | 0 | Village |
| Hollansburg | 25 | 239 | 246 | -0.83% | 1,975 | 0 | Village |
| Gordon | 26 | 228 | 235 | -0.87% | 1,382 | 0 | Village |
| North Star | 27 | 226 | 230 | -0.44% | 441 | 1 | Village |
| Palestine | 28 | 178 | 183 | -0.56% | 1,219 | 0 | Village |
| Rossburg | 29 | 158 | 161 | -0.63% | 1,129 | 0 | Village |
| New Weston | 30 | 123 | 125 | -0.81% | 480 | 0 | Village |
| Castine | 31 | 105 | 107 | -0.94% | 1,382 | 0 | Village |
| Yorkshire | 32 | 103 | 105 | -0.96% | 381 | 0 | Village |
| Ithaca | 33 | 91 | 93 | -1.09% | 2,935 | 0 | Village |
Trotwood is the largest city in Darke County, with a population of 23,071.
Ithaca is the smallest city in Darke County, with a population of 91.
There are 33 cities in Darke County, Ohio.