38 zips
| Zip Code | City | Population ↓ |
|---|---|---|
| 13601 | Watertown | 37,409 |
| 13603 | Watertown | 13,973 |
| 13619 | Carthage | 10,774 |
| 13637 | Evans Mills | 5,280 |
| 13605 | Adams | 5,106 |
| 13624 | Clayton | 4,438 |
| 13634 | Dexter | 3,866 |
| 13691 | Theresa | 3,172 |
| 13656 | La Fargeville | 2,945 |
| 13612 | Black River | 2,940 |
| 13602 | Fort Drum | 2,700 |
| 13606 | Adams Center | 2,397 |
| 13685 | Sackets Harbor | 2,234 |
| 13622 | Chaumont | 2,100 |
| 13607 | Alexandria Bay | 2,061 |
| 13661 | Mannsville | 2,043 |
| 13673 | Philadelphia | 1,983 |
| 13608 | Antwerp | 1,845 |
| 13618 | Cape Vincent | 1,696 |
| 13616 | Calcium | 1,560 |
| 13650 | Henderson | 1,268 |
| 13679 | Redwood | 1,169 |
| 13682 | Rodman | 795 |
| 13615 | Brownville | 538 |
| 13659 | Lorraine | 371 |
| 13693 | Three Mile Bay | 315 |
| 13640 | Wellesley Island | 305 |
| 13611 | Belleville | 265 |
| 13692 | Thousand Island Park | 216 |
| 13628 | Deferiet | 185 |
| 13636 | Ellisburg | 184 |
| 13638 | Felts Mills | 172 |
| 13674 | Pierrepont Manor | 154 |
| 13632 | Depauville | 128 |
| 13651 | Henderson Harbor | 127 |
| 13641 | Fishers Landing | 69 |
| 13675 | Plessis | 51 |
| 13643 | Great Bend | 20 |
The data shown reflect ZCTAs from the US Census. As of 2024, there are 38 ZCTAs in Jefferson County, New York (US Census).