- Sabota Lark
- Saffron Toucanet
- Sage Thrasher
- Sahel Bush Sparrow
- Salvadori's Fig Parrot
- Sandstone Shrikethrush
- Sapphire-vented Puffleg
- Satanic Nightjar
- Satyr Tragopan
- Saw-billed Hermit
- Saxaul Sparrow
- Scale-throated Earthcreeper
- Scaly-breasted Munia
- Scaly Ground Roller
- Scarlet-browed Tanager
- Scarlet-rumped Trogon
- Scarlet Finch
- Scarlet Minivet
- Schlegel's Asity
- Sclater's Nightingale-Thrush
- Scripps's Murrelet
- Sepia-capped Flycatcher
- Serendib Scops Owl
- Serra do Mar Tyrant-Manakin
- Shaft-tailed Whydah
- Sharp-billed Treehunter
- Sharp-tailed Grouse
- Sharp-tailed Streamcreeper
- Shelley's Sparrow
- Short-bearded Melidectes
- Short-tailed Lark
- Shrike-like Tanager
- Shy Albatross
- Siberian Jay
- Sickle-billed Vanga
- Sierra Madre Sparrow
- Silver-eared Mesia
- Silver Gull
- Sinaloa Wren
- Singing Starling
- Sirkeer Malkoha
- Slaty-backed Gull
- Slaty Robin
- Slaty Vireo
- Slender-billed Finch
- Slender-billed Flufftail
- Slender-billed Oriole
- Small Ground Finch
- Small Tree Finch
- Smoky Robin
- Snow Goose
- Snow Mountain Robin
- Somali Short-toed Lark
- Sombre Hummingbird
- Sombre Kingfisher
- Sombre Rock Chat
- Sooty-fronted Spinetail
- Sora
- Southern Antpipit
- Southern Black Flycatcher
- Southern Royal Albatross
- Spanish Sparrow
- Speckled Piculet
- Speckled Wood Pigeon
- Spectacled Guillemot
- Spice Imperial Pigeon
- Spinifex Pigeon
- Spinifexbird
- Splendid Astrapia
- Spot-backed Antshrike
- Spot-breasted Antvireo
- Spot-winged Wood Quail
- Spotted Antbird
- Spotted Bamboowren
- Spotted Bush Warbler
- Spotted Crocias
- Spotted Ground Thrush
- Spotted Honeyeater
- Spotted Laughingthrush
- Spotted Owl
- Spotted Wren
- Squamate Antbird
- Sri Lanka Scimitar Babbler
- Sri Lanka Spurfowl
- Sri Lanka White-eye
- Sri Lanka Wood Pigeon
- Standardwing
- Steller's Sea Eagle
- Stephan's Emerald Dove
- Steppe Eagle
- Straight-billed Earthcreeper
- Streak-breasted Scimitar Babbler
- Streak-headed Honeyeater
- Streak-throated Barwing
- Streaked Shearwater
- Streaked Weaver
- Streaked Xenops
- Striated Babbler
- Striated Bulbul
- Striated Prinia
- Strickland's Woodpecker
- Stripe-breasted Starthroat
- Stripe-throated Yuhina
- Striped Sparrow
- Styan's Grasshopper Warbler
- Subantarctic Snipe
- Subdesert Brush Warbler
- Sulawesi Babbler
- Sulawesi Cicadabird
- Sulawesi Masked Owl
- Sulawesi Scops Owl
- Sulawesi Thrush
- Sulphur-bellied Warbler
- Sulphur-vented Whistler
- Sumatran Babbler
- Sunda Bush Warbler
- Sunda Frogmouth
- Sunda Minivet
- Sunda Scops Owl
- Swamp Francolin
- Sword-billed Hummingbird