| Think in the Circle Ltd | Professional & scientific | 2010 |
| Think Media Consultancy Limited | Professional & scientific | 2009 |
| Think Smart NOT Hard Limited | Administrative & support | 2016 |
| Think Spinc Ltd | Health & social care | 2017 |
| Think Student Ltd | Education | 2020 |
| Third Smile Limited | Financial services | 2026 |
| Third Smile Manchester Limited | Health & social care | 2026 |
| Third Smile Midlands Limited | Health & social care | 2026 |
| Thirdway Advisory Ltd | Professional & scientific | 2020 |
| Thirty-Nine Design Ltd. | Construction | 2015 |
| This Esme Ltd | Information & communication | 2019 |
| This IS Breeze Ltd | Information & communication | 2024 |
| Thisishomeholdings Limited | Real estate | 2021 |
| THM Creative Ltd | Information & communication | 2020 |
| Thoger Limited | Health & social care | 2019 |
| Thomas Flows Limited | Water & waste | 2024 |
| Thomas Psychology Associates Ltd | Education | 2023 |
| Thomas's Medical Ltd | Health & social care | 2015 |
| Thompson Distribution Services Ltd | Construction | 2023 |
| Thompson Homes Education Limited | Education | 2023 |
| Thompson Homes Investment Limited | Real estate | 2014 |
| Thompson Homes Lettings Limited | Real estate | 2016 |
| Thor Juice Limited | Wholesale & retail | 2014 |
| Thorley Holdings Limited | Financial services | 2021 |
| Thorneyfield Developments Ltd | Construction | 2025 |
| Thornside Security Services Ltd | Administrative & support | 2026 |
| Thorpe Heating & Plumbing Limited | Construction | 2011 |
| Thoughtful HR Ltd | Professional & scientific | 2020 |
| Thula Ltd. | Health & social care | 2013 |
| Thurlow Baker Ltd | Financial services | 2026 |
| TIA Brow Bar Ltd | Professional & scientific | 2016 |
| Tickhead Ltd | Financial services | 2023 |
| Tide Group Ltd | Information & communication | 2019 |
| Tide Trading Ltd | Financial services | 2023 |
| Tideswell Auto Ltd | Wholesale & retail | 2025 |
| Tidy Lady Ltd | Wholesale & retail | 2023 |
| Tidy SUM Ltd | Education | 2022 |
| Tilbury Yard Events CIC | Real estate | 2026 |
| Tilbury Yard Ltd | Hospitality | 2026 |
| Tilsmore Homes Ltd | Construction | 2025 |
| TIM Cobb Associates Limited | Professional & scientific | 2002 |
| TIM Cragg Limited | Professional & scientific | 2003 |
| Time Capital (Holdings) Limited | Financial services | 2007 |
| Time Capital Assets Limited | Extraterritorial | 2026 |
| Time Capital Limited | Real estate | 2014 |
| Timeless Prestige Ltd | Wholesale & retail | 2025 |
| Timeline FX Ltd | Information & communication | 2019 |
| Timely Classics Limited | Wholesale & retail | 2004 |
| Tims RPL Limited | Construction | 2022 |
| TIN BIN Ltd | Hospitality | 2018 |
| Tinaco Ltd | Extraterritorial | 2011 |
| Tinderbox Music UK CIC | Information & communication | 2023 |
| Tingley Sparks Electrical Services Limited | Construction | 2017 |
| Tinkatop Global Limited | Professional & scientific | 2025 |
| Tinseltown Ltd | Information & communication | 2025 |
| Tinseltown Trees Ltd | Wholesale & retail | 2020 |
| Tiny Corp Limited | Financial services | 2019 |
| Tiny Town Eastbourne Ltd | Hospitality | 2019 |
| Titan UK Logistics Limited | Transport & logistics | 2017 |
| Tixuy Limited | Information & communication | 2025 |
| TK Carpentry Ltd | Manufacturing | 2024 |
| TK Properties Investment Limited | Real estate | 2026 |
| Tld.Advice Ltd | Information & communication | 2025 |
| Tm&C Ltd | Construction | 2018 |
| TN Nails Eastbourne Ltd | Other services | 2024 |
| TNT Refinishing Limited | Construction | 2015 |
| TO the Rise Limited | Manufacturing | 2021 |
| Toasthaus Studios Limited | Professional & scientific | 2025 |
| Tobias Adam Consulting Limited | Information & communication | 2004 |
| Tobias Peter Ltd | Other services | 2024 |
| Tobytooth Ltd | Health & social care | 2022 |
| Todd UK Limited | Construction | 2003 |
| Together WE CAN Projects CIC | Education | 2025 |
| Tollgate Bramber Limited | Hospitality | 2026 |
| Tollgate Gardens RTM Company Limited | Extraterritorial | 2016 |
| Tollgate RTM Company Limited | Households | 2016 |
| TOM Haley Ecology Limited | Professional & scientific | 2023 |
| Tomango Limited | Professional & scientific | 2012 |
| Tombreezetv Ltd | Extraterritorial | 2011 |
| Tombstone Studios Ltd | Information & communication | 2024 |
| Tommies Guides Limited | Wholesale & retail | 2008 |
| Tommy Rail Ltd | Construction | 2019 |
| Tommy V Comms Ltd | Information & communication | 2025 |
| Tonic Advisory Limited | Professional & scientific | 2026 |
| Tonium Limited | Information & communication | 2012 |
| Tony Pulford Consulting Ltd | Administrative & support | 2023 |
| Tony Wilson Illustration Limited | Professional & scientific | 2008 |
| Tonypiccante Limited | Hospitality | 2020 |
| Tooth and Mouth Limited | Health & social care | 2006 |
| Toothfairy 21 Ltd | Health & social care | 2021 |
| Topagraphics Ltd | Manufacturing | 2023 |
| Topnotch Construction Supplies Ltd | Construction | 2018 |
| Tops Trade Limited | Wholesale & retail | 2010 |
| Topshock Limited | Real estate | 1996 |
| Toreros Eastbourne Ltd | Hospitality | 2022 |
| Torfield Court (Eastbourne) Tenants Association Limited | Households | 1961 |
| Tornado Productions Ltd | Administrative & support | 2023 |
| Torreros Limited | Hospitality | 2018 |
| Toska H Ltd | Real estate | 2018 |
| Total Care Laundry Limited | Administrative & support | 2007 |