| City/Town | Postal Code | Area Code |
| Basin City, WA | 99343 | 509 |
| Connell, WA | 99326 | 509 |
| Eltopia, WA | 99330 | 509 |
| Kahlotus, WA | 99335 | 509 |
| Mesa, WA | 99343 | 509 |
| Pasco, WA | 99301 | 509 |
| 99302 | 509 | |
| Tri Cities, WA | 99302 | 509 |
List of all Cities and Towns in Franklin County, WA alphabetically