- Kalama (Population: 1,783)
- Kelso (Population: 11,895)
- Kenmore (Population: 18,678)
- Kennewick (Population: 54,693)
- Kent (Population: 79,524)
- Kettle Falls (Population: 1,527)
- Kingsgate (Population: 12,222)
- Kingston (Population: 1,611)
- Kirkland (Population: 45,054)
- Kittitas (Population: 1,105)
