- Tacazze Sunbird
- Taczanowski's Ground Tyrant
- Taiga Bean Goose
- Taiga Flycatcher
- Taita Fiscal
- Taita Thrush
- Taita White-eye
- Taiwan Bamboo Partridge
- Taiwan Barbet
- Taiwan Barwing
- Taiwan Blue Magpie
- Taiwan Bush Warbler
- Taiwan Cupwing
- Taiwan Hwamei
- Taiwan Partridge
- Taiwan Rosefinch
- Taiwan Scimitar Babbler
- Taiwan Whistling Thrush
- Taiwan Yuhina
- Tanimbar Corella
- Tanna Fruit Dove
- Taveta Weaver
- Tawny-breasted Parrotfinch
- Tawny-crowned Pygmy Tyrant
- Tawny-flanked Prinia
- Tawny-headed Swallow
- Tawny Antpitta
- Tawny Eagle
- Tawny Frogmouth
- Tawny Owl
- Tawny Piculet
- Tawny Pipit
- Tawny Tit-Spinetail
- Temminck's Courser
- Temminck's Lark
- Temminck's Stint
- Tenerife Blue Chaffinch
- Tepui Brushfinch
- Tepui Goldenthroat
- Terek Sandpiper
- Terrestrial Brownbul
- Tessmann's Flycatcher
- Thekla's Lark
- Thick-billed Euphonia
- Thick-billed Fox Sparrow
- Thick-billed Green Pigeon
- Thick-billed Heleia
- Thick-billed Kingbird
- Thick-billed Murre
- Thick-billed Raven
- Thick-billed Seed Finch
- Thick-billed Seedeater
- Thick-billed Vireo
- Thick-billed Weaver
- Three-banded Courser
- Three-banded Plover
- Three-banded Rosefinch
- Three-streaked Tchagra
- Three-striped Warbler
- Thrush Nightingale
- Tibetan Babax
- Tibetan Lark
- Tibetan Partridge
- Tibetan Rosefinch
- Tibetan Snowfinch
- Tickell's Leaf Warbler
- Timneh Parrot
- Timor Blue Flycatcher
- Timor Cuckoo-Dove
- Timor Leaf Warbler
- Timor Sparrow
- Timor Stubtail
- Tiny Cisticola
- Tiny Sunbird
- Tiny Tyrant-Manakin
- Tit Berrypecker
- Tit Hylia
- Titicaca Grebe
- Tolima Dove
- Tomtit
- Torrent Duck
- Torresian Crow
- Torresian Imperial Pigeon
- Toucan Barbet
- Tourmaline Sunangel
- Townsend's Warbler
- Tree Pipit
- Tree Swallow
- Tricolored Heron
- Trilling Shrike-babbler
- Tropical Gnatcatcher
- Tropical Kingbird
- Tropical Parula
- Trumpeter Finch
- Trumpeter Hornbill
- Trumpeter Swan
- Tufted Duck
- Tufted Puffin
- Tui
- Tullberg's Woodpecker
- Tumbes Hummingbird
- Tumbes Pewee
- Tumbes Tyrant
- Tundra Swan
- Turkey Vulture
- Turquoise Dacnis
- Turquoise Jay
- Turquoise Parrot
- Twelve-wired Bird-of-paradise
- Twite
- Two-banded Puffbird
- Two-barred Crossbill
- Two-barred Warbler
- Tyrian Metaltail