8 zips
| Zip Code | City | Population ↓ |
|---|---|---|
| 43050 | Mount Vernon | 31,074 |
| 43019 | Fredericktown | 9,445 |
| 43028 | Howard | 7,799 |
| 43011 | Centerburg | 6,594 |
| 43014 | Danville | 3,738 |
| 43022 | Gambier | 3,635 |
| 43005 | Bladensburg | 339 |
| 43037 | Martinsburg | 293 |
The data shown reflect ZCTAs from the US Census. As of 2024, there are 8 ZCTAs in Knox County, Ohio (US Census).