Founded in 1852, Jefferson County is one of 39 counties in the state of Washington. Historically, Jefferson County was formed from Thurston County. The city of Port Townsend is the county seat. With FIPS code of 31, Jefferson County has a population of 32,977 and area of 1,804 square miles (4,672 km2).
List of all cities in Jefferson County, WA alphabetically
| City/Town | Postal Code | Area Code |
| Adelma Beach, WA | 98368 | 360/564 |
| Beckett Point, WA | 98368 | 360/564 |
| Brinnon, WA | 98320 | 360/564 |
| Center, WA | 98376 | 360/564 |
| Chimacum, WA | 98325 | 360/564 |
| Dabob, WA | 98376 | 360/564 |
| Discovery Bay, WA | 98368 | 360/564 |
| East Quilcene, WA | 98376 | 360/564 |
| Fort Flagler, WA | 98358 | 360/564 |
| Fort Worden, WA | 98368 | 360/564 |
| Glen Cove, WA | 98368 | 360/564 |
| Hadlock, WA | 98339 | 360/564 |
| Indian Island, WA | 98358 | 360/564 |
| Irondale, WA | 98339 | 360/564 |
| Leland, WA | 98368 | 360/564 |
| Marrowstone Island, WA | 98358 | 360/564 |
| Mats Mats, WA | 98368 | 360/564 |
| Mount Walker, WA | 98376 | 360/564 |
| Nordland, WA | 98358 | 360/564 |
| Oak Bay, WA | 98339 | 360/564 |
| Point Townsend, WA | 98368 | 360/564 |
| Port Hadlock, WA | 98339 | 360/564 |
| 98365 | 360/564 | |
| Port Ludlow, WA | 98365 | 360/564 |
| Port Townsend, WA | 98368 | 360/564 |
| Protection Island, WA | 98368 | 360/564 |
| Quilcene, WA | 98376 | 360/564 |
| Shine, WA | 98325 | 360/564 |
| Townsend, WA | 98368 | 360/564 |