7 zips
| Zip Code | City | Population ↓ |
|---|---|---|
| 52353 | Washington | 9,072 |
| 52327 | Riverside | 3,722 |
| 52356 | Wellman | 2,754 |
| 52248 | Keota | 1,572 |
| 52201 | Ainsworth | 1,359 |
| 52621 | Crawfordsville | 620 |
| 52359 | West Chester | 344 |
The data shown reflect ZCTAs from the US Census. As of 2024, there are 7 ZCTAs in Washington County, Iowa (US Census).