Founded in Dec 9, 1800, Fairfield County is one of 88 counties in the state of Ohio. Historically, Fairfield County was formed from Ross and Washington Counties. The city of Lancaster is the county seat. With FIPS code of 45, Fairfield County has a population of 161,064 and area of 505.11 square miles (1,308 km2).
List of all cities in Fairfield County, OH alphabetically
| City/Town | Postal Code | Area Code |
| Amanda, OH | 43102 | 740 |
| Baltimore, OH | 43105 | 740 |
| Bremen, OH | 43107 | 740 |
| Carroll, OH | 43112 | 614/380 |
| Hide Away Hills, OH | 43107 | 740 |
| Hideaway Hls, OH | 43107 | 740 |
| Lancaster, OH | 43130 | 740 |
| Lithopolis, OH | 43136 | 740 |
| Millersport, OH | 43046 | 740 |
| Pickerington, OH | 43147 | 614/380 |
| Pleasantville, OH | 43148 | 740 |
| Rushville, OH | 43150 | 740 |
| 43163 | 740 | |
| Stoutsville, OH | 43154 | 740 |
| Sugar Grove, OH | 43155 | 740 |
| Thurston, OH | 43157 | 740 |
| West Rushville, OH | 43163 | 740 |