- Spanaway
- Spanaway Mobile Village
- Spangle
- Spee-Bi-Dah
- Speelyai
- Spencer Island
- Sperry
- Spieden Island
- Spirit
- Split Rock
- Spokane
- Spokane Valley
- Sprague
- Spring Beach
- Spring Beach
- Spring Glen
- Spring Valley
- Spring Valley Mobile Home Park
- Springdale
- Spruce West Mobile Home Park
- Squaw Island
- Squaw Islands
- Squaxin Island
- Squire Mobile Home Park
- Stabler
- Staley
- Stampede
- Stanwood
- Star Lake
- Starbuck