- Sacred Kingfisher
- Salvin's Albatross
- Sanderling
- Sandwich Tern
- Sardinian Warbler
- Sarus Crane
- Satin Bowerbird
- Scaly-feathered Weaver
- Scarlet Macaw
- Scintillant Hummingbird
- Semicollared Flycatcher
- Semipalmated Plover
- Semipalmated Sandpiper
- Senegal Parrot
- Sharp-tailed Sandpiper
- Short-eared Owl
- Short-toed Snake Eagle
- Siberian Jay
- Silver Gull (scopulinus)
- Silvereye
- Singing Honeyeater
- Slaty Flowerpiercer
- Slender-billed Gull
- Snow Bunting
- Snowy Albatross
- Sociable Weaver
- Song Thrush
- South Island Robin
- South Island Takahe
- Southern Bald Ibis
- Southern Grey-headed Sparrow
- Southern Pied Babbler
- Southern Red-billed Hornbill
- Southern Red Bishop
- Southern Royal Albatross
- Spanish Sparrow
- Speckled Pigeon
- Spectacled Warbler
- Spot-billed Pelican
- Spotless Starling
- Spotted Flycatcher
- Spotted Sandpiper
- Spotted Shag
- Squacco Heron
- Stitchbird
- Striated Heron
- Sunda Zebra Finch
- Superb Fairywren
- Swainson's Spurfowl
- Swamp Sparrow