15 zips
| Zip Code | City | Population ↓ |
|---|---|---|
| 45750 | Marietta | 26,485 |
| 45714 | Belpre | 9,333 |
| 45742 | Little Hocking | 3,447 |
| 45784 | Vincent | 3,089 |
| 45786 | Waterford | 3,019 |
| 45767 | New Matamoras | 2,566 |
| 45744 | Lowell | 2,164 |
| 45729 | Fleming | 2,149 |
| 45724 | Cutler | 1,597 |
| 45768 | Newport | 1,566 |
| 45788 | Whipple | 1,021 |
| 45773 | Reno | 516 |
| 45746 | Macksburg | 301 |
| 45789 | Wingett Run | 177 |
| 45721 | Coal Run | 32 |
The data shown reflect ZCTAs from the US Census. As of 2024, there are 15 ZCTAs in Washington County, Ohio (US Census).