15 ZIP Codes
| Zip Code | City | Population ↓ |
|---|---|---|
| 45750 | Marietta | 26,420 |
| 45714 | Belpre | 9,503 |
| 45742 | Little Hocking | 3,752 |
| 45786 | Waterford | 3,187 |
| 45784 | Vincent | 3,002 |
| 45767 | New Matamoras | 2,428 |
| 45744 | Lowell | 2,179 |
| 45729 | Fleming | 2,121 |
| 45768 | Newport | 1,503 |
| 45724 | Cutler | 1,218 |
| 45788 | Whipple | 691 |
| 45773 | Reno | 600 |
| 45746 | Macksburg | 329 |
| 45789 | Wingett Run | 280 |
| 45721 | Coal Run | 15 |
The data shown reflect ZCTAs from the US Census. As of 2025, there are 15 ZCTAs in Washington County, Ohio (US Census).