- Sabattus
- Saddleback Inc.
- Saint Agatha
- Saint Albans
- Saint Francis
- Saint John
- Sandy River
- Sangerville
- Searsmont
- Searsport
- Sebec
- Seboeis
- Sedgwick
- Shapleigh
- Skowhegan
- Smithfield
- Somerville
- Sorrento
- South Berwick
- South Bristol
- South Eliot
- South Paris
- South Portland Gardens
- South Sanford
- South Thomaston
- South Windham
- Southport
- Southwest Harbor
- Springvale
- Stacyville
- Standish
- Starks
- Steep Falls
- Stetson
- Steuben
- Stockholm
- Stockton Springs
- Stonington
- Strong
- Sugarloaf
- Sullivan
- Sumner
- Sunday River
- Surry
- Swans Island
- Swanville
