| Tracey ANN Distribution Ltd | Wholesale & retail | 2024 |
| Tracey Construction Ltd | Construction | 2025 |
| TRACK2TEST Ltd | Professional & scientific | 2009 |
| Trackimo UK Limited | Wholesale & retail | 2013 |
| Tracy’S Stellar Retreat Limited | Real estate | 2025 |
| Trafck Ltd | Information & communication | 2024 |
| Trans Insulation Ltd | Manufacturing | 2013 |
| Transmaxx UK Ltd | Transport & logistics | 2019 |
| Traxen Ltd | Construction | 2018 |
| Trayned Bandes Limited | Administrative & support | 2010 |
| Treasurewells Accountancy & Consultancy Ltd | Other services | 2016 |
| Treasurewells Properties Ltd | Real estate | 2022 |
| Treasurewells Resources Ltd | Other services | 2018 |
| Treasurewells Services Ltd | Real estate | 2023 |
| Treasury Gates Limited | Professional & scientific | 2019 |
| Treblejay Consulting Ltd | Professional & scientific | 2021 |
| TREES4GOOD Limited | Agriculture & fishing | 2024 |
| TREES4GROWTH Limited | Agriculture & fishing | 2024 |
| Trevatt Design Ltd | Professional & scientific | 2023 |
| Trident Environmental Solutions Limited | Construction | 2021 |
| Trident Utilities and Civils Ltd. | Water & waste | 2019 |
| Trifecta Property Management Ltd | Real estate | 2025 |
| Triggerads Ltd | Professional & scientific | 2022 |
| Trinity Gardens (Gravesend) NO.1 Residents Company Limited | Households | 1991 |
| Triple Edge Training Limited | Education | 2025 |
| Triple TEE Property Investment Limited | Real estate | 2021 |
| Tripleo&A Ltd | Health & social care | 2021 |
| Troost Film Company Ltd | Information & communication | 2026 |
| True Care Staffing Recruitment Ltd | Administrative & support | 2025 |
| True Clear Garage Co Ltd | Water & waste | 2026 |
| True Power Technology Co., Ltd | Manufacturing | 2024 |
| Trueability Ltd | Health & social care | 2024 |
| Truelife Healthcare Ltd | Administrative & support | 2019 |
| TRV Pharma Limited | Wholesale & retail | 2014 |
| TS Accounting Dorset Limited | Real estate | 2020 |
| TS Accounting Southwest Limited | Professional & scientific | 2007 |
| TSH Taxi Ltd | Transport & logistics | 2025 |
| Tshuma Transport Limited | Transport & logistics | 2018 |
| TSJ Investments Ltd | Construction | 2019 |
| TSL Construction Ltd | Professional & scientific | 2025 |
| Tubabs Limited | Health & social care | 2021 |
| TUC Construction Ltd | Construction | 2017 |
| Tulip Food Centre Limited | Wholesale & retail | 2004 |
| Tunde Akinsola Ltd | Real estate | 2022 |
| Tundra Sense Ltd | Professional & scientific | 2021 |
| Tunshopping Ltd | Other services | 2019 |
| Tunstall Trading Limited | Administrative & support | 2017 |
| TUO PU International Machinery Trade Co., Ltd | Wholesale & retail | 2023 |
| Turkish Grill Kent Ltd | Hospitality | 2025 |
| Turner Rigging Ltd | Construction | 2021 |
| Turngreen Ventures Ltd | Information & communication | 2024 |
| Turtlereality Limited | Information & communication | 2012 |
| Turvey Property Services Limited | Financial services | 2017 |
| Tutela Earth Limited | Professional & scientific | 2016 |
| Tuwonk Ltd | Information & communication | 2022 |
| TVT Drive Ltd | Transport & logistics | 2014 |
| TW Consult Limited | Other services | 2016 |
| TW Farm Ltd | Agriculture & fishing | 2020 |
| Twin & Earth Electrical Ltd | Manufacturing | 2025 |
| Twist Media Consulting Ltd | Professional & scientific | 2018 |
| Twisted Fuse Ltd | Professional & scientific | 2023 |
| Twydall Carpets Limited | Wholesale & retail | 1974 |
| Twymans Mill Management Company Limited | Households | 1990 |
| TXD Steel Group Co., Ltd | Manufacturing | 2023 |
| TXT 2000 Software Limited | Information & communication | 2000 |
| Tyner Properties Limited | Households | 2025 |
| Tyre Resolve Ltd | Wholesale & retail | 2016 |
| U&S Flux Limited | Wholesale & retail | 2025 |
| U.H.S Trading Limited | Real estate | 2018 |
| Ubique 24 Ltd | Professional & scientific | 2014 |
| Ubuncare Limited | Information & communication | 2025 |
| Udder Investments Limited | Real estate | 2023 |
| UFG FX Ltd | Financial services | 2017 |
| UFG Holdings Ltd | Financial services | 2023 |
| UK Airports Ltd | Other services | 2017 |
| UK Boho Cafe Ltd | Wholesale & retail | 2024 |
| UK Bros Ltd | Wholesale & retail | 2026 |
| UK Detailing and Valeting Limited | Wholesale & retail | 2020 |
| UK EDU Care Limited | Education | 2022 |
| UK Eduzone Ltd | Education | 2023 |
| UK Home Supplies Limited | Wholesale & retail | 2018 |
| UK Land & Assets Ltd | Real estate | 2020 |
| UK Myer Chemical Industry Co., Ltd. | Extraterritorial | 2023 |
| UK Office Cleaning Ltd | Administrative & support | 2023 |
| UK Petrogate Ltd | Information & communication | 2010 |
| UK Policing Security Services Ltd | Administrative & support | 2017 |
| UK SAN York Mining Co., Ltd | Agriculture & fishing | 2025 |
| UK YZ Agrotech Corp Limited | Agriculture & fishing | 2025 |
| Ulela Chemical Group Ltd | Wholesale & retail | 2019 |
| Ulivo Consulting Limited | Information & communication | 2023 |
| Ulrix Law Limited | Professional & scientific | 1997 |
| Ultimakind Care Partners Limited | Health & social care | 2025 |
| Ultimate Drive Company Limited | Health & social care | 2015 |
| Ultimate Home Improvements Ltd | Construction | 2012 |
| Ultimet Architectural Limited | Extraterritorial | 2014 |
| Ultimet Group Limited | Extraterritorial | 2014 |
| Ultimet Industrial Limited | Extraterritorial | 2014 |
| Ultra CNC Machining Co., Ltd | Manufacturing | 2019 |
| Umba London Ltd | Wholesale & retail | 2025 |
| Umoya Trust (UK) | Health & social care | 2009 |