| Tabagam Island | Fakfak | 0.00 km² | — | — |
| Tabako Island | Raja Ampat | 0.01 km² | — | — |
| Tabar Island | Aru Islands Regency | 5.26 km² | — | 1 m |
| Tabar Island | Aru Islands Regency | 0.27 km² | — | — |
| Tabarfufun Island | Aru Islands Regency | 0.00 km² | — | — |
| Tabby Tabby Island | Queensland | — | — | 2 m |
| Tabek Island | Raja Ampat | 0.68 km² | — | — |
| Tabek Mgun Island | Raja Ampat | 0.10 km² | — | 10 m |
| Tabelomani Island | Raja Ampat | 0.00 km² | — | — |
| Tabelomaniyef Island | Raja Ampat | 0.00 km² | — | — |
| Taberaknanam Island | Fakfak | 0.21 km² | — | — |
| Taberfane | Maluku | — | — | 25 m |
| Tabiteuea | Gilbert Islands | 37.6 km² | 5,477 | 3 m |
| Table Island | New South Wales | — | — | 4 m |
| Tabuaeran | Line Islands | 33.7 km² | 2,539 | 3 m |
| Tafahi | Niuas | 3.42 km² | 31 | 546 m |
| Tafer Island | Fakfak | 3.09 km² | — | — |
| Taffy Island | Queensland | — | — | 20 m |
| Tafir Island | Aru Islands Regency | 0.48 km² | — | — |
| Tagunnawahia Island | Aru Islands Regency | 0.02 km² | — | — |
| Tagur Island | Aru Islands Regency | 2.42 km² | — | — |
| Tait Island | Queensland | — | — | 3 m |
| Takangaroa Island | Auckland Region | — | — | 21 m |
| Takuiwahia Island | Aru Islands Regency | 0.00 km² | — | — |
| Takuu Atoll | Autonomous Region of Bougainville | 2 km² | — | 2 m |
| Talbaul Island | Aru Islands Regency | 0.47 km² | — | — |
| Talbaulgoriri Island | Aru Islands Regency | 0.01 km² | — | — |
| Talikbibi Kecil Island | Tanimbar Islands | 0.00 km² | — | — |
| Tam Island | Tual | 13.3 km² | — | 82 m |
| Tamadawinin Island | Aru Islands Regency | 0.00 km² | — | — |
| Tamagui Island | Raja Ampat | 0.38 km² | — | 55 m |
| Tamaitemioka Island | Southland District | — | — | 90 m |
| Tamana | Gilbert Islands | 4.50 km² | 951 | — |
| Tamar Island | Tasmania | — | — | 3 m |
| Tamata Deman Island | Aru Islands Regency | 0.38 km² | — | — |
| Tamatarasuo Island | Teluk Bintuni | 20.1 km² | — | — |
| Tamba Island | Teluk Bintuni | 17.0 km² | — | — |
| Tambur Pat Island | Raja Ampat | 0.00 km² | — | — |
| Tambur Sawi Island | Raja Ampat | 0.02 km² | — | — |
| Tamoni Island | Teluk Wondama | 0.02 km² | — | — |
| Tamoni Kecil Selatan Island | Teluk Wondama | 0.00 km² | — | — |
| Tamoni Kecil Utara Island | Teluk Wondama | 0.00 km² | — | — |
| Tampea Island | Aru Islands Regency | 0.00 km² | — | — |
| Tamtulal Island | Raja Ampat | 0.00 km² | — | — |
| Tanaf Natuk Island | Fakfak | 0.01 km² | — | — |
| Tanaf Nenem Island | Fakfak | 0.03 km² | — | — |
| Tancred Island | Queensland | — | — | 34 m |
| Tandula Island | Tanimbar Islands | 7.10 km² | — | 4 m |
| Tanger Island | Aru Islands Regency | 0.13 km² | — | — |
| Tangwain Island | Southeast Maluku | 0.48 km² | — | 26 m |
| Tanimbar Kei Island | Southeast Maluku | 9.80 km² | — | 14 m |
| Tanjong Island | Fakfak | 0.00 km² | — | — |
| Tanjung Gaidesi Jina Island | Aru Islands Regency | 0.07 km² | — | — |
| Tanjung Gaidesi Sisiay Island | Aru Islands Regency | 0.11 km² | — | — |
| Tanjung Pasirlauran Island | Tanimbar Islands | 0.00 km² | — | — |
| Tanna | Tafea | 555 km² | 28,799 | 389 m |
| Taongtaong Island | Fakfak | 0.00 km² | — | — |
| Tapakbus Genan Island | Raja Ampat | 0.00 km² | — | — |
| Tapakbus Lol Island | Raja Ampat | 0.00 km² | — | — |
| Tapakbus Peley Island | Raja Ampat | 0.00 km² | — | — |
| Tapapai Island | Teluk Wondama | 0.02 km² | — | — |
| Tapianpop Island | Raja Ampat | 0.00 km² | — | — |
| Tapor Ai Kayai Island | Raja Ampat | 0.00 km² | — | — |
| Tapor Anyaf Island | Raja Ampat | 0.00 km² | — | — |
| Tapor Doi Island | Raja Ampat | 0.00 km² | — | — |
| Tapor Ingkintus | Raja Ampat | 0.00 km² | — | — |
| Tapor Inkir | Raja Ampat | 0.00 km² | — | — |
| Tapor Ipyoper | Raja Ampat | 0.00 km² | — | — |
| Tapor Kapar Island | Raja Ampat | 0.00 km² | — | — |
| Tapor Mangkubre | Raja Ampat | 0.00 km² | — | — |
| Tapor Ranso | Raja Ampat | 0.06 km² | — | — |
| Tapor Ruwin Island | Raja Ampat | 0.01 km² | — | — |
| Tapor Tabitatu | Raja Ampat | 0.00 km² | — | — |
| Taporiswek Selatan Island | Raja Ampat | 0.00 km² | — | — |
| Taporiswek Tengah Island | Raja Ampat | 0.00 km² | — | — |
| Taporiswek Utara Island | Raja Ampat | 0.01 km² | — | — |
| Taptopon Lek Island | Raja Ampat | 0.01 km² | — | — |
| Tapuranusa Natuk Island | Fakfak | 0.00 km² | — | — |
| Taputerangi | Napier City | — | — | 25 m |
| Tarahiki Island | Auckland Region | 0.06 km² | 0 | 68 m |
| Tarakuning Besar Island | Fakfak | 0.00 km² | — | — |
| Tarakuning Kecil Island | Fakfak | 0.00 km² | — | — |
| Taralanggera Island | Fakfak | 0.00 km² | — | — |
| Taramnusa Barat Island | Fakfak | 0.00 km² | — | — |
| Taramnusa Natuk Island | Fakfak | 0.00 km² | — | — |
| Taramnusa Nenem Island | Fakfak | 0.04 km² | — | — |
| Taramnusa Tengah Island | Fakfak | 0.00 km² | — | — |
| Taramnusa Timur Island | Fakfak | 0.00 km² | — | — |
| Tarawai Island | East Sepik Province | 4 km² | — | — |
| Tareerpattel-tarerenner / Ninth Island | Tasmania | 32 km² | — | 25 m |
| Tarfa Island | Fakfak | 0.00 km² | — | — |
| Tarfarfar Island | Fakfak | 0.01 km² | — | — |
| Tariramata Island | Fakfak | 0.39 km² | — | — |
| Taris Ai Island | Fakfak | 0.04 km² | — | — |
| Taris Island | Fakfak | 0.00 km² | — | — |
| Tarise Island | Fakfak | 0.01 km² | — | — |
| Taruk Induwaf Island | Raja Ampat | 0.00 km² | — | — |
| Taruk Indwaf Island | Raja Ampat | 0.00 km² | — | — |
| Tarwa Island | Southeast Maluku | 1.24 km² | — | 25 m |
| Tasiranbaju Island | Raja Ampat | 1.28 km² | — | 25 m |
| Tasman Island | Tasmania | 1.20 km² | — | 235 m |
| Tasmania | Tasmania | 65,022 km² | 536,600 | 1,009 m |
| Tasod Island | Raja Ampat | 0.00 km² | — | — |
| Tasodyeben Island | Raja Ampat | 0.00 km² | — | — |
| Tatana | National Capital District | 0.48 km² | — | — |
| Tatosiwori Island | Teluk Wondama | 0.00 km² | — | — |
| Tatul Island | Raja Ampat | 0.00 km² | — | — |
| Tatulbus Island | Raja Ampat | 0.01 km² | — | — |
| Tatun Balengan Island | Tanimbar Islands | 0.00 km² | — | — |
| Tatunwatyoki Island | Tanimbar Islands | 0.00 km² | — | — |
| Taukihepa / Big South Cape Island | Southland District | 9.39 km² | — | 235 m |
| Taulagap'a Island | Samoa | — | — | 130 m |
| Taumaka Island | Westland District | — | — | 30 m |
| Taumeasina Island | Samoa | — | — | 9 m |
| Taupiri Island | Northland Region | 3.80 km² | 0 | 69 m |
| Tauwitchere Island | South Australia | — | — | 2 m |
| Tavaerua | Cook Islands | — | — | 7 m |
| Taval Island | Tanimbar Islands | 0.04 km² | — | 23 m |
| Taveuni | Cakaudrove | 434 km² | 19,000 | 1,241 m |
| Taw Alifuru Island | Raja Ampat | 0.01 km² | — | — |
| Taw Famani Island | Raja Ampat | 0.01 km² | — | — |
| Tawa Island | Sorong | 0.11 km² | — | — |
| Tawaya Island | Sorong | 0.10 km² | — | — |
| Tayando Island | Tual | 26.6 km² | — | 32 m |
| Taylor Island | South Australia | — | — | 59 m |
| Te Au Ot | Cook Islands | — | — | 3 m |
| Te Haupa Island | Auckland Region | — | — | 35 m |
| Te Hauturu-o-Toi / Little Barrier Island | Auckland Region | 28.2 km² | 0 | 722 m |
| Te Hāwere-a-Maki / Goat Island | Auckland Region | 0.10 km² | — | — |
| Te Kahaatuwai Island | Wairoa District | — | — | 954 m |
| Te Kainga | Cook Islands | — | — | 13 m |
| Te Motu o Tarakapoe | Cook Islands | — | — | 6 m |
| Te Motu-o-Kura / Bare Island | Hawke's Bay Region | 15 km² | — | 106 m |
| Te Pa | Cook Islands | — | — | 6 m |
| Te Ruerue Iti | Cook Islands | — | — | 14 m |
| Te Ruerue Rahi | Cook Islands | — | — | 4 m |
| Te Toka-Tapu-a-Kupe / Ninepin Rock | Auckland Region | — | — | 29 m |
| Tea Tree Island | New South Wales | — | — | 92 m |
| Teague Island | Queensland | — | — | 45 m |
| Teal Island | New South Wales | — | — | 1,211 m |
| Teal Island | South Australia | — | — | 1 m |
| Teatree Island | New South Wales | — | — | 92 m |
| Teddy Bear Island | Victoria | — | — | 136 m |
| Tefa Island | New Ireland Province | 4 km² | — | — |
| Tefartefar Island | Fakfak | 0.00 km² | — | — |
| Tegua | Torba | 30.7 km² | 58 | 139 m |
| Tehapai | Cook Islands | — | — | 5 m |
| Tekef Island | Raja Ampat | 0.00 km² | — | — |
| Tekopi Island | Yapen Islands | 0.00 km² | — | — |
| Telagoi Island | Raja Ampat | 0.01 km² | — | — |
| Teleme Island | Sorong | 1.89 km² | — | 24 m |
| Temangtemang Island | Jayapura | 0.00 km² | — | — |
| Temple Island | Queensland | — | — | 11 m |
| Templer Island | Northern Territory | — | — | 13 m |
| Temun Island | Aru Islands Regency | 0.04 km² | — | — |
| Temwen Island | Pohnpei State | 3 km² | — | — |
| Tench Island | New Ireland Province | 0.50 km² | 100 | — |
| Tenef Island | Raja Ampat | 0.00 km² | — | — |
| Tengah Island | Aru Islands Regency | 0.04 km² | — | — |
| Tenggiriwamar Nus Island | Raja Ampat | 0.00 km² | — | — |
| Tengkorak Island | Raja Ampat | 0.01 km² | — | — |
| Tenth Island | Tasmania | 900 km² | 0 | — |
| Teor Island | Eastern Seram | 21.9 km² | 2,556 | 115 m |
| Teraina | Line Islands | 14.2 km² | 1,893 | 5 m |
| Terangan Island | Aru Islands Regency | 2,149 km² | — | 14 m |
| Teri Island | Tanimbar Islands | 0.26 km² | — | — |
| Terilbah Island | New South Wales | — | — | 5 m |
| Tern Island | Queensland | 0.08 km² | — | 8 m |
| Tern Islet | Queensland | — | — | 3 m |
| Tern Rock | Tasmania | — | — | 13 m |
| Terrille Island | New South Wales | — | — | 200 m |
| Tetanoi Island | Aru Islands Regency | 0.08 km² | — | — |
| Teteruga Atsa Island | Raja Ampat | 0.00 km² | — | — |
| Teteruga Lu Island | Raja Ampat | 0.00 km² | — | — |
| Teteruga Tol Island | Raja Ampat | 0.00 km² | — | — |
| Tevusa Island | Aru Islands Regency | 1.10 km² | — | — |
| Tey Peley Island | Raja Ampat | 0.00 km² | — | — |
| The Beehives | Tasmania | — | — | 1,035 m |
| The Brothers | South Australia | — | — | 6 m |
| The Carbuncle | Tasmania | 0.02 km² | — | — |
| The Child | Queensland | — | — | 49 m |
| The Chinamans Garden | New South Wales | — | — | 11 m |
| The Chinamens | New South Wales | — | — | 11 m |
| The Chinamens Island | New South Wales | — | — | 11 m |
| The Images | Tasmania | — | — | 16 m |
| The Island | New South Wales | — | — | 291 m |
| The Island | New South Wales | — | — | 165 m |
| The Island | New South Wales | — | — | 273 m |
| The Island | New South Wales | — | — | 152 m |
| The Island | Tasmania | — | — | 510 m |
| The Island | Victoria | — | — | 44 m |
| The Island | Victoria | — | — | 1 m |
| The Island | Victoria | — | — | 9 m |
| The Island | Victoria | — | — | 294 m |
| The Lanterns | Tasmania | — | — | 32 m |
| The Monument | Tasmania | — | — | 3 m |
| The Monuments | South Australia | — | — | 4 m |
| The Nangus Island | New South Wales | — | — | 202 m |
| The Nobbies | Victoria | — | — | 15 m |
| The Nuggets | Tasmania | — | — | 105 m |
| The Pages | New South Wales | — | — | 5 m |
| The Pineapple | Tasmania | — | — | 412 m |
| The Pound | New South Wales | — | — | 534 m |
| The Pyramid | Chatham Islands Territory | 0.10 km² | 0 | — |
| Thion | Sanma | — | — | 213 m |
| Thistle Island | New South Wales | — | — | 182 m |
| Thistle Island | South Australia | — | — | 214 m |
| Thomas Island | Queensland | — | — | 6 m |
| Thomas Island | Queensland | — | — | 81 m |
| Thomas Island | Queensland | — | — | 1 m |
| Thooloora Island | Queensland | — | — | 15 m |
| Thorny Island | New South Wales | — | — | 3 m |
| Thorpe Island | Queensland | — | — | 73 m |
| Three Hummock Island | Circular Head | 70 km² | 0 | 237 m |
| Three Month Island | Queensland | — | — | 12 m |
| Three Sisters | Tasmania | — | — | 3 m |
| Thrum Cap | Southland District | — | — | 51 m |
| Thunder Island | Queensland | — | — | 6 m |
| Thurk Island | South Australia | — | — | 17 m |
| Thursday Island | Queensland | 3.50 km² | 2,938 | 104 m |
| Tia Island / Entrance | Southland District | — | — | 30 m |
| Tide Island | Queensland | — | — | 10 m |
| Tide Island | Queensland | — | — | 20 m |
| Tidegauge Rock | Tasmania | — | — | 1 m |
| Tifanunusa Barat Island | Fakfak | 0.00 km² | — | — |
| Tifanunusa Tengah Island | Fakfak | 0.00 km² | — | — |
| Tifanunusa Timur Island | Fakfak | 0.00 km² | — | — |
| Tiga Besar Island | Aru Islands Regency | 0.01 km² | — | — |
| Tiga Kecil Selatan Island | Aru Islands Regency | 0.26 km² | — | — |
| Tiga Kecil Utara Island | Aru Islands Regency | 0.00 km² | — | — |
| Tik Island | Queensland | — | — | 15 m |
| Tilarfufun Island | Aru Islands Regency | 0.05 km² | — | — |
| Tima | Cook Islands | — | — | 6 m |
| Timintui Ndabe Island | Kaimana | 0.01 km² | — | — |
| Timintui Nit Island | Kaimana | 0.00 km² | — | — |
| Timore Island / Chimneys | Southland District | — | — | 66 m |
| Tims Island | New South Wales | — | — | 52 m |
| Tinana Island | Queensland | — | — | 8 m |
| Tinkers Rock | Tasmania | — | — | 7 m |
| Tinonee Peak Island | Queensland | — | — | 119 m |
| Tinpot Island | Tasmania | — | — | 2 m |
| Tinsmith Island | Queensland | — | — | 80 m |
| Tip Facan Island | Raja Ampat | 0.02 km² | — | — |
| Tip Island | Victoria | — | — | 1 m |
| Tip Kapas Island | Raja Ampat | 0.00 km² | — | — |
| Tipale Island | Raja Ampat | 0.54 km² | — | — |
| Tipinupai Island | Raja Ampat | 0.00 km² | — | — |
| Tiplo Island | Raja Ampat | 0.00 km² | — | — |
| Tipoaret Island | Fakfak | 0.01 km² | — | — |
| Tipoaret Island | Fakfak | 0.01 km² | — | — |
| Tipolo Island | Raja Ampat | 0.01 km² | — | — |
| Tippecan Island | Raja Ampat | 0.00 km² | — | — |
| Tipplers Island | Queensland | — | — | 6 m |
| Tiritiri Matangi Island | Auckland Region | 2.20 km² | 0 | 80 m |
| Tita Island | Aru Islands Regency | 0.00 km² | — | — |
| Titernoha Island | Fakfak | 0.01 km² | — | — |
| Titi Island | Marlborough District | 0.32 km² | 0 | — |
| Titim Island | Fakfak | 0.02 km² | — | — |
| Titima / Trefoil Island | Circular Head | — | — | 6 m |
| Titpegam Genan Island | Raja Ampat | 0.00 km² | — | — |
| Titpegam Island | Raja Ampat | 0.00 km² | — | — |
| To Nut Island | Raja Ampat | 0.00 km² | — | — |
| Toayef Les Island | Raja Ampat | 0.00 km² | — | — |
| Toayef Lool Island | Raja Ampat | 0.01 km² | — | — |
| Toayef Sawi Island | Raja Ampat | 0.01 km² | — | — |
| Toba Island | Aru Islands Regency | 0.85 km² | — | 11 m |
| Tobeloyen Atsa Island | Raja Ampat | 0.00 km² | — | — |
| Tobeloyen Fat Island | Raja Ampat | 0.00 km² | — | — |
| Tobeloyen Lu Island | Raja Ampat | 0.00 km² | — | — |
| Tobeloyen Tol Island | Raja Ampat | 0.00 km² | — | — |
| Tobi | Hatohobei | 0.60 km² | 20 | 3 m |
| Tobin Island | Queensland | 0.05 km² | 0 | 10 m |
| Tobur Island | Tanimbar Islands | 0.13 km² | — | — |
| Tofongarijuri Island | Aru Islands Regency | 0.00 km² | — | — |
| Tofua | Haʻapai district | 55.6 km² | 200 | 515 m |
| Toga | Torba | 18.8 km² | 276 | 104 m |
| Togoannusa Island | Fakfak | 0.00 km² | — | — |
| Toke Atoll | Marshall Islands | 0.57 km² | — | 0.30 m |
| Token Island | Victoria | — | — | 202 m |
| Tol | Chuuk | 10.3 km² | 5,129 | — |
| Tol Sepatu Island | Raja Ampat | 0.00 km² | — | — |
| Tolar Island | Aru Islands Regency | 0.00 km² | — | — |
| Tolesi Island | Sorong | 0.47 km² | — | — |
| Tolesi Kecil Island | Sorong | 0.02 km² | — | — |
| Tolobi Island | Raja Ampat | 0.42 km² | — | — |
| Toltoljurin Gaga Island | Aru Islands Regency | 0.00 km² | — | — |
| Toltoljurin Island | Aru Islands Regency | 11.3 km² | — | 16 m |
| Tomahawk Island | Tasmania | — | — | 21 m |
| Tomai Island | Yapen Islands | 0.01 km² | — | — |
| Tomato Island | Queensland | — | — | 14 m |
| Tomayen Island | New South Wales | — | — | 6 m |
| Tomman Island | Malampa | — | — | 1 m |
| Tommys Island | New South Wales | — | — | 1 m |
| Tomyar Da Island | Tanimbar Islands | 0.00 km² | — | — |
| Tong Island | Papua New Guinea | 25 km² | 400 | — |
| Tonga Island | Tasman District | 0.15 km² | — | 83 m |
| Tongariki | Shefa | — | — | 20 m |
| Tongatapu | Tongatapu | 260.5 km² | 71,260 | — |
| Tonggorongrogrog Island | Fakfak | 0.04 km² | — | — |
| Tongoa | Shefa | 41 km² | 2,300 | 191 m |
| Tongot Les Island | Raja Ampat | 0.00 km² | — | — |
| Tongot Lol Island | Raja Ampat | 0.00 km² | — | — |
| Tonton Island | Aru Islands Regency | 0.34 km² | — | — |
| Tonys Island | New South Wales | — | — | 52 m |
| Tonys Point Island | New South Wales | — | — | 1 m |
| Tooth Island | Queensland | — | — | 4 m |
| Top Island | Raja Ampat | 0.01 km² | — | — |
| Top Island | New South Wales | — | — | 133 m |
| Top Island | Queensland | — | — | 144 m |
| Top Island | Victoria | — | — | 111 m |
| Top-Gallant Isles | South Australia | — | — | 10 m |
| Topa Le Island | Raja Ampat | 0.00 km² | — | — |
| Topa Lol Island | Raja Ampat | 0.00 km² | — | — |
| Torin Island | Tanimbar Islands | 0.28 km² | — | — |
| Tormyar Island | Tanimbar Islands | 0.00 km² | — | — |
| Torrens Island | South Australia | 7.69 km² | — | 3 m |
| Torrens Island | New South Wales | — | — | 1 m |
| Tortor Island | Aru Islands Regency | 0.07 km² | — | — |
| Totoya | Lau | 28 km² | — | — |
| Towagery Island | The Coorong | — | — | 3 m |
| Towatchery Island | The Coorong | — | — | 3 m |
| Towatwa Pale Island | Raja Ampat | 0.00 km² | — | — |
| Tower Hill Island | Victoria | — | — | 75 m |
| Townshend Island | Queensland | — | — | 26 m |
| Trappes Island | Tasmania | — | — | 304 m |
| Travers Island | Queensland | — | — | 25 m |
| Treble Island | Queensland | — | — | 5 m |
| Tree Island | Queensland | — | — | 10 m |
| Triangle Island | Queensland | — | — | 13 m |
| Triangle Island | New South Wales | — | — | 1 m |
| Triangular Island | Queensland | — | — | 14 m |
| Trochus Island | Queensland | 1.60 km² | 0 | 14 m |
| Troubridge Island | South Australia | 2 km² | — | 5 m |
| Truant Island | Northern Territory | — | — | 20 m |
| Trut Ndoku Island | Tanimbar Islands | 0.00 km² | — | — |
| Tryon Island | Queensland | — | — | 10 m |
| Tual Island | Tanimbar Islands | 0.67 km² | — | 12 m |
| Tualmalawan Island | Tanimbar Islands | 0.01 km² | — | — |
| Tuamotu Island | Gisborne District | — | — | 38 m |
| Tuari Island | Fakfak | 0.01 km² | — | — |
| Tuaua | Cook Islands | — | — | 4 m |
| Tub Island | Aru Islands Regency | 1.38 km² | — | — |
| Tubirserang Island | Fakfak | 0.05 km² | — | 2 m |
| Tuboi Island | Aru Islands Regency | 0.37 km² | — | — |
| Tuckean Island | New South Wales | — | — | 5 m |
| Tuckers Island | New South Wales | — | — | 1 m |
| Tudu Island | Queensland | — | — | 10 m |
| Tufir Besar Island | Fakfak | 0.03 km² | — | — |
| Tufir Kecil Island | Fakfak | 0.00 km² | — | — |
| Tufir Tengah Island | Fakfak | 0.02 km² | — | — |
| Tugarpuannerawain Selatan Island | Fakfak | 0.00 km² | — | — |
| Tugarpuannerawain Tengah Island | Fakfak | 0.00 km² | — | — |
| Tuhawaiki Island | Otago Region | 7.80 km² | — | — |
| Tujuh Barat Island | Aru Islands Regency | 0.01 km² | — | — |
| Tujuh Tengah Island | Aru Islands Regency | 0.01 km² | — | — |
| Tujuh Timur Island | Aru Islands Regency | 0.00 km² | — | — |
| Tujullo Island | Raja Ampat | 0.00 km² | — | — |
| Tuk Island | Raja Ampat | 0.00 km² | — | — |
| Tulaha Island | Aru Islands Regency | 2.59 km² | — | — |
| Tulburrerr Island | Queensland | 0.41 km² | — | — |
| Tuleen Island | Queensland | — | — | 5 m |
| Tullaberga Island | Victoria | — | — | 7 m |
| Tumamori Island | Yapen Islands | 0.00 km² | — | — |
| Tumby Island | South Australia | — | — | 13 m |
| Tumit Island | Fakfak | 0.00 km² | — | — |
| Tumpapa Island | Yapen Islands | 0.00 km² | — | — |
| Tunaa Klaa Island | Tanimbar Islands | 0.00 km² | — | — |
| Tuncetau Island | Raja Ampat | 0.00 km² | — | — |
| Tungkwarisa Island | Aru Islands Regency | 0.23 km² | — | — |
| Tunglok Ganan Island | Raja Ampat | 0.00 km² | — | — |
| Tunglok Pale Island | Raja Ampat | 0.00 km² | — | — |
| Tupaimi Island | Sorong | 0.34 km² | — | — |
| Tupaimi Kecil Island | Sorong | 0.12 km² | — | — |
| Tupuaekaha | Cook Islands | — | — | 5 m |
| Turkey Island | Queensland | — | — | 1 m |
| Turkey Island | New South Wales | — | — | 5 m |
| Turn Island | Queensland | — | — | 60 m |
| Turnagain Island | Queensland | 12.0 km² | 0 | 16 m |
| Turners Camp Island | Queensland | — | — | 4 m |
| Turners Island | New South Wales | — | — | 65 m |
| Turners Island | Victoria | — | — | 123 m |
| Turtle Head Island | Queensland | 12.8 km² | — | 19 m |
| Turtle Island | Queensland | 0.04 km² | 0 | — |
| Turtle Island | Queensland | — | — | 14 m |
| Turtle Island | Queensland | — | — | 11 m |
| Turtle Island | Queensland | — | — | 29 m |
| Turtle Island | Northern Territory | — | — | 14 m |
| Turu Cay | Queensland | 0.08 km² | 0 | — |
| Tutuba Island | Samna | — | — | 1 m |
| Tutun Funjai Island | Tanimbar Islands | 0.00 km² | — | — |
| Tutun Island | Tanimbar Islands | 0.02 km² | — | — |
| Tutununusa Island | Fakfak | 0.02 km² | — | 37 m |
| Tuvuca | Lau | 12 km² | — | — |
| Tuwtuwan Island | Tanimbar Islands | 0.03 km² | — | — |
| Tuyam | Milne Bay Province | 0.16 km² | — | 50 m |
| Tweed Island | Queensland | — | — | 41 m |
| Tween Island | Queensland | — | — | 13 m |
| Twi Island | Tanimbar Islands | 0.11 km² | — | — |
| Twin Island | Queensland | — | — | 48 m |
| Tynemouth Island | Queensland | — | — | 12 m |
| Tāhuahua-Paopao-Karoro Island | Far North District | 0.22 km² | 0 | — |