- South Bancroft
- South Limington
- South Sugarloaf Island
- Southern Island
- Sand Island
- Sabattus
- Sabino
- Saco
- Saddle Island
- Saddleback Island
- Sagamore Village
- Sail Rock
- Saint Agatha
- Saint Albans
- Saint Clair Island
- Saint Croix Island
- Saint Croix Junction
- Saint David
- Saint Francis
- Saint George
- Saint Helena Island
- Saint John
- Sal Seal Island
- Salem
- Sally Island
- Sally Island
- Sally Islands
- Salmon Falls
- Salmon Island
- Salsbury Cove