Communities
| Cities |
| Galion (partially in Richland County) |
| Mansfield (County Seat) |
| Ontario |
| Shelby |
| Villages |
| Bellville |
| Butler |
| Crestline (partially located in Richland County) |
| Lexington |
| Lucas |
| Plymouth (partially located in Richland County) |
| Shiloh |
| Townships |
| Blooming Grove |
| Butler |
| Cass |
| Franklin |
| Jackson |
| Jefferson |
| Madison |
| Mifflin |
| Monroe |
| Perry |
| Plymouth |
| Sandusky |
| Sharon |
| Springfield |
| Troy |
| Washington |
| Weller |
| Worthington |
