18 zips
| Zip Code | City | Population ↓ |
|---|---|---|
| 21740 | Hagerstown | 62,760 |
| 21742 | Hagerstown | 34,549 |
| 21713 | Boonsboro | 9,999 |
| 21783 | Smithsburg | 9,866 |
| 21795 | Williamsport | 9,772 |
| 21722 | Clear Spring | 6,709 |
| 21782 | Sharpsburg | 4,389 |
| 21750 | Hancock | 3,613 |
| 21756 | Keedysville | 3,303 |
| 21746 | Hagerstown | 2,613 |
| 21779 | Rohrersville | 1,731 |
| 21733 | Fairplay | 1,202 |
| 21719 | Cascade | 1,145 |
| 21767 | Maugansville | 873 |
| 21711 | Big Pool | 864 |
| 21734 | Funkstown | 861 |
| 21781 | Saint James | 41 |
| 21715 | Brownsville | 12 |
The data shown reflect ZCTAs from the US Census. As of 2024, there are 18 ZCTAs in Washington County, Maryland (US Census).