7 zips
| Zip Code | City | Population ↓ |
|---|---|---|
| 52353 | Washington | 8,930 |
| 52327 | Riverside | 3,691 |
| 52356 | Wellman | 2,577 |
| 52248 | Keota | 1,655 |
| 52201 | Ainsworth | 1,508 |
| 52621 | Crawfordsville | 899 |
| 52359 | West Chester | 422 |
The data shown reflect ZCTAs from the US Census. As of 2024, there are 7 ZCTAs in Washington County, Iowa (US Census).