- Sage Thrasher
- Sand Martin
- Sanderling
- Sandwich Tern
- Sardinian Warbler
- Scopoli's Shearwater
- Sedge Warbler
- Short-eared Owl
- Siberian Jay
- Silvereye
- Slender-billed Gull
- Snow Bunting
- Snowy Egret
- Song Sparrow
- Song Thrush
- Sooty Tern
- Spanish Sparrow
- Speckled Pigeon
- Spotless Starling
- Spotted Dove
- Spotted Flycatcher
- Spotted Redshank
- Spotted Sandpiper
- Spotted Towhee
- Steller's Jay
- Swainson's Hawk
- Swainson's Thrush
- Swamp Harrier