Founded in May 1, 1803, Warren County is one of 88 counties in the state of Ohio. Historically, Warren County was formed from Hamilton County. The city of Lebanon is the county seat. With FIPS code of 165, Warren County has a population of 246,553 and area of 399.63 square miles (1,035 km2).
List of all cities in Warren County, OH alphabetically
| City/Town | Postal Code | Area Code |
| Blue Ball, OH | 45005 | 513/283 |
| Butlerville, OH | 45162 | 513/283 |
| Carlisle, OH | 45005 | 513/283 |
| Corwin, OH | 45068 | 513/283 |
| Edenton, OH | 45162 | 513/283 |
| Foster, OH | 45039 | 513/283 |
| Franklin, OH | 45005 | 513/283 |
| Hamilton Township, OH | 45039 | 513/283 |
| Harveysburg, OH | 45032 | 513/283 |
| Kings Island, OH | 45034 | 513/283 |
| Kings Mills, OH | 45034 | 513/283 |
| Landon, OH | 45039 | 513/283 |
| Lebanon, OH | 45036 | 513/283 |
| Liberty Township, OH | 45036 | 513/283 |
| Lytle, OH | 45068 | 513/283 |
| Maineville, OH | 45039 | 513/283 |
| Mason, OH | 45040 | 513/283 |
| Massie, OH | 45032 | 513/283 |
| Morrow, OH | 45152 | 513/283 |
| Mount Holly, OH | 45068 | 513/283 |
| Oregonia, OH | 45054 | 513/283 |
| Pleasant Plain, OH | 45162 | 513/283 |
| South Lebanon, OH | 45065 | 513/283 |
| Springboro, OH | 45066 | 513/283 |
| Waynesville, OH | 45068 | 513/283 |