Founded in 1870, Loudon County is one of 95 counties in the state of Tennessee. Historically, Loudon County was formed from Roane, Monroe, Blount and McMinn counties. The city of Loudon is the county seat. With FIPS code of 105, Loudon County has a population of 56,690 and area of 229 square miles (593 km2).
List of all cities in Loudon County, TN alphabetically
| City/Town | Postal Code | Area Code |
| Greenback, TN | 37742 | 865 |
| Lenoir City, TN | 37771 | 865 |
| 37772 | 865 | |
| Loudon, TN | 37774 | 865 |
| Philadelphia, TN | 37846 | 865 |