7 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Mansfield | 1 | 47,627 | 47,525 | 0.04% | 1,543 | 31 | City |
| Shelby | 2 | 9,212 | 9,289 | -0.14% | 1,459 | 6 | City |
| Ontario | 3 | 6,638 | 6,668 | -0.08% | 599 | 11 | City |
| Bellville | 4 | 2,012 | 1,960 | 0.45% | 706 | 3 | Village |
| Butler | 5 | 935 | 943 | -0.11% | 725 | 1 | Village |
| Shiloh | 6 | 610 | 616 | -0.16% | 666 | 1 | Village |
| Lucas | 7 | 584 | 589 | -0.17% | 863 | 1 | Village |
Mansfield is the largest city in Richland County, with a population of 47,627.
Lucas is the smallest city in Richland County, with a population of 584.
There are 7 cities in Richland County, Ohio.