10 zips
| Zip Code | City | Population ↓ |
|---|---|---|
| 64506 | Saint Joseph | 22,241 |
| 64507 | Saint Joseph | 14,316 |
| 64503 | Saint Joseph | 12,033 |
| 64501 | Saint Joseph | 10,567 |
| 64504 | Saint Joseph | 10,348 |
| 64443 | Easton | 1,734 |
| 64401 | Agency | 1,299 |
| 64448 | Faucett | 935 |
| 64440 | De Kalb | 904 |
| 64484 | Rushville | 819 |
The data shown reflect ZCTAs from the US Census. As of 2024, there are 10 ZCTAs in Buchanan County, Missouri (US Census).