8 zips
| Zip Code | City | Population ↓ |
|---|---|---|
| 43050 | Mount Vernon | 30,360 |
| 43019 | Fredericktown | 9,517 |
| 43028 | Howard | 8,063 |
| 43011 | Centerburg | 6,978 |
| 43014 | Danville | 4,185 |
| 43022 | Gambier | 3,621 |
| 43005 | Bladensburg | 308 |
| 43037 | Martinsburg | 265 |
The data shown reflect ZCTAs from the US Census. As of 2024, there are 8 ZCTAs in Knox County, Ohio (US Census).