| Tropical Reef Aquatics Ltd | Wholesale & retail | 2019 |
| Troubleshooterz Ltd | Information & communication | 2011 |
| Trplogistick Ltd | Transport & logistics | 2026 |
| Truck & Trade Limited | Transport & logistics | 2025 |
| Trucking DG Limited | Transport & logistics | 2024 |
| True Parity Consulting Limited | Other services | 2020 |
| True Services UK Ltd | Wholesale & retail | 2024 |
| True Shield Roofing Ltd | Construction | 2025 |
| True Tiles and Bathrooms Limited | Wholesale & retail | 2020 |
| Truedrive Autos Ltd | Wholesale & retail | 2026 |
| Trueform Digital Limited | Manufacturing | 2017 |
| Trueform Engineering Holdings EBT Limited | Manufacturing | 2015 |
| Trueform Engineering Holdings Limited | Manufacturing | 2011 |
| Trueform Engineering Limited | Manufacturing | 1977 |
| Truesigns Limited | Wholesale & retail | 2025 |
| Truestar Limited | Professional & scientific | 2024 |
| Truguard Security Ltd | Administrative & support | 2025 |
| Truly Humble Ltd | Wholesale & retail | 2024 |
| Truspex Industries Limited | Wholesale & retail | 2026 |
| Trustblock Construction Ltd | Construction | 2024 |
| Trustway Transport Ltd | Transport & logistics | 2025 |
| TS Accessories Ltd | Information & communication | 2016 |
| TS Consultancy Solutions Limited | Professional & scientific | 2021 |
| TS Convenience Store Ltd | Wholesale & retail | 2023 |
| TS Elite UK Construction Ltd | Construction | 2025 |
| TS Food & Wine Ltd | Wholesale & retail | 2015 |
| TS Property Maintenance Ltd | Construction | 2023 |
| TSC Solutions Ltd | Professional & scientific | 2026 |
| TSD Foods Ltd | Wholesale & retail | 2020 |
| TSG Studios Ltd | Education | 2025 |
| TSK Estate Ltd | Real estate | 2024 |
| TSK Haulage Ltd | Administrative & support | 2016 |
| TSK Transports Ltd | Manufacturing | 2018 |
| TSM Assets Ltd | Real estate | 2022 |
| TSN Academy Limited | Education | 2016 |
| TSP 3 Ltd | Professional & scientific | 2024 |
| TSQ Resources Ltd | Professional & scientific | 2024 |
| TSU Constructions Ltd | Construction | 2015 |
| Ttluxevents Ltd | Hospitality | 2025 |
| Tucker DE Vere Limited | Real estate | 1998 |
| Tugra Restaurant Limited | Hospitality | 2017 |
| Tujaar Ltd | Wholesale & retail | 2025 |
| Tulip Mart Ltd | Wholesale & retail | 2026 |
| Tumodeste Ltd | Health & social care | 2013 |
| Tung Developers Ltd | Construction | 2025 |
| Turban Beatz Limited | Information & communication | 2014 |
| Turbo Transportation Ltd | Transport & logistics | 2024 |
| Turna Construction Ltd | Construction | 2021 |
| Turna Ltd | Real estate | 2020 |
| Turna Transport Ltd | Transport & logistics | 2025 |
| Turnaup Ltd | Wholesale & retail | 2023 |
| Tusk MAN and Van Removals Ltd | Transport & logistics | 2025 |
| TVN Limited | Wholesale & retail | 2018 |
| TWB Heathrow Business Centre Ltd | Real estate | 2020 |
| TWB London Events Ltd | Other services | 2021 |
| TWB Parking Ltd | Transport & logistics | 2021 |
| Two Stones One Bird Ltd | Manufacturing | 2023 |
| Twohustlers Ltd | Wholesale & retail | 2024 |
| TXY Ltd | Construction | 2025 |
| Tymacy Ltd | Professional & scientific | 2015 |
| TYRES24HOURS Limited | Wholesale & retail | 2019 |
| U Homey Ltd | Real estate | 2023 |
| U K Builders (TT) Ltd | Construction | 2018 |
| U&G Investments Ltd | Real estate | 2020 |
| U&U Trading Ltd | Wholesale & retail | 2024 |
| U.S Builder Services Limited | Construction | 2021 |
| UASIE-79 Limited | Transport & logistics | 2004 |
| UB Builders Ltd | Construction | 2010 |
| UB Chicken Ltd | Hospitality | 2025 |
| UB1 Investments Limited | Real estate | 2026 |
| UB4 Construction Ltd | Construction | 2018 |
| UB4 Properties Limited | Real estate | 2024 |
| UBER7PLUS.COM Limited | Transport & logistics | 2019 |
| Uberrimae Fidei (London) Ltd | Transport & logistics | 2016 |
| Ubhi Projects Ltd | Construction | 2023 |
| Ubhi Repairs Ltd | Construction | 2026 |
| Ubits Limited | Wholesale & retail | 2024 |
| UBX Cargo Solutions Limited | Transport & logistics | 2025 |
| UBX UK Ltd | Wholesale & retail | 2015 |
| Ucas Portal Ltd | Education | 2024 |
| Ucontrol Solutions Limited | Administrative & support | 2018 |
| Ucorb Ltd | Other services | 1998 |
| Udaj Limited | Professional & scientific | 2013 |
| Udaya Realities Limited | Financial services | 2015 |
| UDI Limited | Real estate | 2010 |
| Ugpool Ltd | Wholesale & retail | 2024 |
| UK Accredeting Services Limited | Professional & scientific | 2020 |
| UK Automotive Sales Ltd | Wholesale & retail | 2022 |
| UK Brothers Roofing Ltd | Construction | 2023 |
| UK Car Trim Ltd | Wholesale & retail | 2023 |
| UK Carpet Hub Ltd | Construction | 2025 |
| UK Cosmetics Ltd | Wholesale & retail | 2025 |
| UK Employment Ltd | Other services | 2017 |
| UK Fast Cargo Ltd | Wholesale & retail | 2020 |
| UK Food & Wine Battersea Ltd | Wholesale & retail | 2017 |
| UK Home 1 Limited | Real estate | 2024 |
| UK Home Design Ltd | Construction | 2023 |
| UK Innovation Ltd | Professional & scientific | 2008 |
| UK Learning Solutions Ltd | Education | 2017 |
| UK Online Bargain Limited | Extraterritorial | 2017 |