- Tapes philippinarum
- Tectura testudinalis
- Tellimya ferruginosa
- Tellina donacina
- Tellina fabula
- Tellina pygmaea
- Tellina tenuis
- Tenellia adspersa
- Teredo navalis
- Teredora malleolus
- Teretia teres
- Tergipes tergipes
- Teuthowenia megalops
- Thecacera pennigera
- Theodoxus fluviatilis
- Thracia convexa
- Thracia distorta
- Thracia papyracea
- Thracia villosiuscula
- Thyasira croulinensis
- Thyasira equalis
- Thyasira ferruginea
- Thyasira flexuosa
- Thyasira gouldi
- Thyasira sarsi
- Timoclea ovata
- Todarodes sagittatus
- Todaropsis eblanae
- Tonicella marmoreus
- Tonicella rubra
- Tornus subcarinatus
- Trichotropis borealis
- Tricolia picta
- Tritonia hombergi
- Tritonia lineata
- Tritonia plebeia
- Trivia arctica
- Trivia monacha
- Trophon barvicensis
- Trophon clathratus
- Trophon muricatus
- Trophon truncatus
- Troschelia berniciensis
- Turbonilla crenata
- Turbonilla jeffreysii
- Turbonilla lactea
- Turbonilla rufescens
- Turritella communis
- Turtonia minuta
- Typhlomangelia nivalis