- Stony Island
- Stover Corner
- Stover Island
- Summer Harbor
- Sunshine
- Sutton Island
- Sandhill Corner
- Sawyer Island
- Sheepscot
- Smutty Nose Island
- South Dresden
- South Jefferson
- South Newcastle
- South Waldoboro
- Southport Island
- Spectacle Island
- Spectacle Islands
- Sprague Corner
- Spruce Shores
- Spruceworld
- Squirrel Island
- Sanderson Corners
- Scott Island
- Seaveys Corner
- Seaward Mills
- Sennetts Corner
- Sevenmile Island
- Sheep Island
- South Albion
- South Gardiner