Founded in 1852, Island County is one of 39 counties in the state of Washington. Historically, Island County was formed from Thurston County. The city of Coupeville is the county seat. With FIPS code of 29, Island County has a population of 86,857 and area of 209 square miles (541 km2).
List of all cities in Island County, WA alphabetically
| City/Town | Postal Code | Area Code |
| Ault Field, WA | 98277 | 360/564 |
| Camano Island, WA | 98282 | 360/564 |
| Clinton, WA | 98236 | 360/564 |
| Coupeville, WA | 98239 | 360/564 |
| Freeland, WA | 98249 | 360/564 |
| Greenbank, WA | 98253 | 360/564 |
| Langley, WA | 98260 | 360/564 |
| Maxwelton, WA | 98236 | 360/564 |
| Nas Whidbey, WA | 98278 | 360/564 |
| Oak Harbor, WA | 98277 | 360/564 |
| 98278 | 360/564 | |
| Possession, WA | 98236 | 360/564 |
| Stanwood, WA | 98282 | 360/564 |
| Whidbey Island Naval Air, WA | 98278 | 360/564 |
| Whidbey Nas, WA | 98278 | 360/564 |