- Seavey Island
- Seven Islands
- Seven Sisters Islands
- Severance
- Shaker Village
- Shapleigh Island
- Sharon
- Shaws Corner
- Shaws Hill
- Sheep Island
- Shel Al Mobile Estates
- Shelburne
- Shelter Island
- Shingle Mill Corner
- Ship Island
- Short Falls
- Silver Lake
- Sixmile Island
- Slab City
- Sleepers Island
- Smith Colony
- Smith Corner
- Smiths Corner
- Smithtown
- Smithville
- Snowville
- Snumshire
- Snyders Hill
- Somersworth
- South Acworth