- Shorewood
- Shorewood Beach
- Shuck Island
- Shumway
- Sibley
- Sicily
- Sidell
- Sidney
- Star Subdivision
- Sigel
- Signal Hill
- Sikkemas Trailer Park
- Silent Meadow
- Siloam
- Silver Glen Meadows
- Silver Lake
- Silvis
- Simmons Island
- Simpson
- Sims
- Sinclair
- Sixmile Island
- Skare Estates
- Skelton
- Ski Hill
- Skiersch's Subdivision
- Skinner Island
- Skinney Island
- Skokie
- Skokie Highlands