33 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Steubenville | 1 | 18,007 | 18,149 | -0.16% | 1,709 | 10.54 | City |
| Island Creek township | 2 | 9,897 | 10,239 | -0.62% | 237 | 41.76 | Township |
| Cross Creek township | 3 | 7,555 | 7,843 | -0.67% | 241 | 31.29 | Township |
| Toronto | 4 | 5,118 | 5,297 | -0.7% | 2,453 | 2.09 | City |
| Knox township | 5 | 4,179 | 4,307 | -0.55% | 144 | 29.12 | Township |
| Steubenville township | 6 | 3,935 | 4,097 | -0.73% | 525 | 7.50 | Township |
| Wintersville | 7 | 3,616 | 3,766 | -0.82% | 1,157 | 3.13 | Village |
| Dillonvale | 8 | 3,277 | 3,411 | -0.4% | 3,674 | 0.89 | CDP |
| Mingo Junction | 9 | 3,200 | 3,342 | -0.87% | 1,190 | 2.69 | Village |
| Smithfield township | 10 | 2,902 | 3,005 | -0.62% | 77 | 37.56 | Township |
| Wells township | 11 | 2,357 | 2,442 | -0.63% | 88 | 26.81 | Township |
| Mount Pleasant township | 12 | 2,135 | 2,223 | -0.74% | 112 | 19.09 | Township |
| Tiltonsville | 13 | 1,204 | 1,256 | -0.82% | 2,298 | 0.52 | Village |
| Saline township | 14 | 1,119 | 1,159 | -0.62% | 53 | 21.09 | Township |
| Richmond township | 15 | 1,000 | 1,011 | -0.1% | 40 | 25.25 | Township |
| Brilliant | 16 | 964 | 1,302 | -3.5% | 552 | 1.75 | CDP |
| Richmond township | 17 | 944 | 970 | -0.53% | 37 | 25.47 | Township |
| Yorkville | 18 | 925 | 967 | -0.86% | 1,563 | 0.59 | Village |
| Adena | 19 | 634 | 664 | -0.94% | 1,181 | 0.54 | Village |
| Dillonvale | 20 | 589 | 614 | -0.84% | 1,526 | 0.39 | Village |
| Bergholz | 21 | 520 | 542 | -0.76% | 924 | 0.56 | Village |
| Amsterdam | 22 | 418 | 437 | -0.95% | 1,306 | 0.32 | Village |
| Richmond | 23 | 394 | 411 | -0.76% | 712 | 0.55 | Village |
| Brush Creek township | 24 | 378 | 392 | -0.53% | 16 | 23.66 | Township |
| Rayland | 25 | 376 | 393 | -0.79% | 795 | 0.47 | Village |
| Mount Pleasant | 26 | 375 | 392 | -0.79% | 1,471 | 0.26 | Village |
| Irondale | 27 | 310 | 325 | -0.96% | 214 | 1.45 | Village |
| Stratton | 28 | 257 | 264 | -0.39% | 479 | 0.54 | Village |
| Empire | 29 | 223 | 228 | -0.45% | 743 | 0.30 | Village |
| New Alexandria | 30 | 219 | 231 | -0.9% | 597 | 0.37 | Village |
| East Springfield | 31 | 139 | 263 | 6.92% | 339 | 0.41 | CDP |
| Bloomingdale | 32 | 133 | 138 | -0.75% | 1,511 | 0.09 | Village |
| Pottery Addition | 33 | 52 | 139 | -23.53% | 61 | 0.85 | CDP |
Steubenville is the largest city in Jefferson County, with a population of 18,007.
Pottery Addition is the smallest city in Jefferson County.
There are 33 cities in Jefferson County, Ohio.