4 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Lenoir City | 1 | 12,519 | 10,126 | 3.97% | 1,451 | 9 | City |
| Loudon | 2 | 7,172 | 6,022 | 3.31% | 567 | 13 | City |
| Greenback | 3 | 1,253 | 1,107 | 2.37% | 151 | 8 | City |
| Philadelphia | 4 | 700 | 610 | 2.64% | 450 | 2 | City |
Lenoir City is the largest city in Loudon County, with a population of 12,519.
Philadelphia is the smallest city in Loudon County, with a population of 700.
There are 4 cities in Loudon County, Tennessee.