23 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Mansfield | 1 | 47,828 | 47,535 | 0.12% | 1,549 | 30.87 | City |
| Shiloh | 2 | 13,174 | 11,681 | 7.14% | 3,364 | 3.92 | CDP |
| Shelby | 3 | 9,247 | 9,286 | -0.09% | 1,465 | 6.31 | City |
| Sharon township | 4 | 8,964 | 9,007 | -0.12% | 372 | 24.08 | Township |
| Butler township | 5 | 8,223 | 8,272 | 0% | 528 | 15.57 | Township |
| Ontario | 6 | 6,647 | 6,662 | -0.05% | 600 | 11.08 | City |
| Butler township | 7 | 6,639 | 6,662 | 0.14% | 201 | 33.05 | Township |
| Washington township | 8 | 6,572 | 6,601 | -0.12% | 206 | 31.95 | Township |
| Mifflin township | 9 | 6,096 | 6,107 | -0.07% | 277 | 22.02 | Township |
| Butler township | 10 | 3,458 | 3,560 | -0.52% | 105 | 32.88 | Township |
| Worthington township | 11 | 2,988 | 2,990 | -0.03% | 83 | 35.85 | Township |
| Roseland | 12 | 2,294 | 1,678 | 7.15% | 3,508 | 0.65 | CDP |
| Bellville | 13 | 2,000 | 1,965 | 0.35% | 702 | 2.85 | Village |
| Weller township | 14 | 1,873 | 1,882 | -0.16% | 77 | 24.27 | Township |
| Cass township | 15 | 1,602 | 1,612 | -0.19% | 62 | 25.66 | Township |
| Butler township | 16 | 1,426 | 1,450 | -0.28% | 41 | 34.60 | Township |
| Bloominggrove township | 17 | 1,290 | 1,291 | 0% | 51 | 25.26 | Township |
| Butler township | 18 | 1,259 | 1,299 | -0.71% | 52 | 24.26 | Township |
| Butler township | 19 | 1,183 | 1,181 | 0.08% | 47 | 25.44 | Township |
| Butler | 20 | 934 | 943 | -0.21% | 724 | 1.29 | Village |
| Lincoln Heights | 21 | 859 | 867 | 7.11% | 1,615 | 0.53 | CDP |
| Shiloh | 22 | 612 | 616 | -0.16% | 668 | 0.92 | Village |
| Lucas | 23 | 586 | 590 | -0.17% | 866 | 0.68 | Village |
Mansfield is the largest city in Richland County, with a population of 47,828.
Lucas is the smallest city in Richland County.
There are 23 cities in Richland County, Ohio.