- Sabine's Gull
- Sanderling
- Sandwich Tern
- Sardinian Warbler
- Savi's Warbler
- Sedge Warbler
- Short-eared Owl
- Short-toed Snake Eagle
- Short-toed Treecreeper
- Siberian Stonechat
- Slender-billed Gull
- Smew
- Snow Bunting
- Snowy Owl
- Solitary Sandpiper
- Song Thrush
- Spanish Imperial Eagle
- Spectacled Warbler
- Spotless Starling
- Spotted Crake
- Spotted Flycatcher
- Spotted Redshank
- Spotted Sandpiper
- Squacco Heron
- Stilt Sandpiper
- Surf Scoter
- Swan Goose