| Tryology Limited | Wholesale & retail | 2025 |
| TS Domestics Community Movement CIC | Administrative & support | 2026 |
| TS Domestics Limited | Wholesale & retail | 2021 |
| TS Domestics Logistics Ltd | Transport & logistics | 2023 |
| TS Insulations Ltd | Construction | 2013 |
| TS Motorsport Limited | Manufacturing | 2026 |
| TS1 Consulting Ltd | Professional & scientific | 2025 |
| TSA Advanced Pharma Solutions Ltd | Health & social care | 2025 |
| TSA Construction Ltd | Construction | 2019 |
| TSA Properties Limited | Real estate | 2020 |
| TSA Rental Ltd | Real estate | 2024 |
| TSB Management Company Ltd | Households | 2022 |
| TSE Property Developments Limited | Construction | 2017 |
| TSL Car Trading Ltd | Wholesale & retail | 2019 |
| Tsvaira Limited | Administrative & support | 2025 |
| TT Projects & Holdings Ltd | Wholesale & retail | 2017 |
| TT Racing Ltd | Wholesale & retail | 2020 |
| TTI Success Insights (UK) Limited | Administrative & support | 2012 |
| TTS INT Ltd | Transport & logistics | 2019 |
| Tttutoring Ltd | Education | 2025 |
| Tubuso Ltd | Wholesale & retail | 2025 |
| Tudor Chestergate Limited | Real estate | 2021 |
| Tudor Driving Limited | Manufacturing | 2019 |
| Tudor FRN Ltd | Manufacturing | 2023 |
| Tudor's Property and Maintenance Ltd | Real estate | 2024 |
| Tudor-Davies Funeral Services Ltd | Other services | 2019 |
| Tudor-Davies Funeral Support Services Limited | Other services | 2023 |
| Tudor-Davies Ltd | Transport & logistics | 2019 |
| Tuktuk Creative Marketing Ltd | Professional & scientific | 2016 |
| Tulbure Motos Ltd | Wholesale & retail | 2017 |
| Tulip Heating & Cooling Solutions Ltd | Wholesale & retail | 2019 |
| Tulip Nursery Limited | Education | 2019 |
| Tulley Property Services Ltd | Households | 2024 |
| Tuncombe Limited | Real estate | 1977 |
| Tuney Tech Engineering Ltd | Construction | 2019 |
| Tungate Group Ltd. | Professional & scientific | 2016 |
| Tungate Print & Packaging Limited | Manufacturing | 1984 |
| Tungate Print Limited | Professional & scientific | 1993 |
| Tunstall Thai Gym Limited | Other services | 2026 |
| Tunstall Together C.I.C. | Arts & recreation | 2025 |
| Tunstall Tuition Centre Limited | Education | 2026 |
| Tunstall Tyrehub Ltd | Wholesale & retail | 2025 |
| Tureline Payroll Solution Limited | Professional & scientific | 2025 |
| Turmeric Indian Ltd | Hospitality | 2024 |
| Turn Left Consultancy Limited | Real estate | 2025 |
| Turners Building Contractors Ltd | Construction | 2017 |
| Turnhill Homes Ltd | Real estate | 2024 |
| Turnhurst Properties Ltd | Real estate | 2016 |
| Turpentine Vintage Limited | Wholesale & retail | 2022 |
| Tutorage C.I.C. | Education | 2019 |
| Tutors Point Ltd | Education | 2025 |
| Tuwame Cosmetics Limited | Wholesale & retail | 2026 |
| TVI Holdings Limited | Real estate | 2025 |
| TW1N Customs Limited | Manufacturing | 2017 |
| TWA Stoke Limited | Arts & recreation | 2025 |
| Tweats Electrical Services Limited | Other services | 2023 |
| TWENTY4 ZERO4 Limited | Construction | 2024 |
| TWENTYFOUR11 Ltd | Administrative & support | 2025 |
| Twickenham Health Limited | Health & social care | 2025 |
| Twin&Two Ltd | Wholesale & retail | 2025 |
| Twist Chair Ltd | Wholesale & retail | 2025 |
| Twitt Twoo Limited | Wholesale & retail | 2025 |
| Twmad Community Interest Company | Education | 2015 |
| Twmad Properties Ltd | Education | 2021 |
| Two CAN Clean Ltd | Administrative & support | 2015 |
| Two Feet Forward Ltd | Financial services | 2023 |
| Twobees Group Ltd | Construction | 2025 |
| Twocees Cuts Ltd | Other services | 2020 |
| Tycoon Autos Ltd | Wholesale & retail | 2023 |
| Tyli Holdings Ltd | Financial services | 2024 |
| Tyre Industry Publications Limited | Information & communication | 1971 |
| Tyre Works Ltd | Wholesale & retail | 2025 |
| TYRES99 Tyre Shop Ltd | Wholesale & retail | 2025 |
| Tyretech Training Academy Ltd | Wholesale & retail | 2025 |
| Tyretech Workforce UK Ltd | Administrative & support | 2026 |
| U Store U Lock (Stoke) Limited | Administrative & support | 2020 |
| U&Man's Ltd | Wholesale & retail | 2023 |
| U.K. Event Catering Limited | Hospitality | 2004 |
| U.K. Marquees Limited | Manufacturing | 1996 |
| U.K. Security Shutters Limited | Administrative & support | 1996 |
| UA Accountancy Limited | Professional & scientific | 2021 |
| Uasquares Limited | Wholesale & retail | 2025 |
| UBI Ltd | Wholesale & retail | 2003 |
| UCB Academy Limited | Extraterritorial | 2019 |
| UCB Digital Ltd | Professional & scientific | 2010 |
| UCB Europe Limited | Professional & scientific | 1995 |
| UCB Extra Ltd | Professional & scientific | 2013 |
| UCB Prayerline Limited | Extraterritorial | 2019 |
| UCL Retail Limited | Wholesale & retail | 2004 |
| UCS Automation Limited | Construction | 2006 |
| UCS Developments Limited | Manufacturing | 2022 |
| Udallsfield Allotment Association Limited | Agriculture & fishing | 2015 |
| Uftrade Ltd | Wholesale & retail | 2024 |
| Uhlsport (UK) Limited | Extraterritorial | 2006 |
| UK Aluminium Products Limited | Wholesale & retail | 2026 |
| UK AMH Traders Ltd | Wholesale & retail | 2026 |
| UK Architecture Ltd | Extraterritorial | 2022 |
| UK BEE Removers (Ukbr) Ltd | Other services | 2021 |
| UK Care Excel Ltd | Health & social care | 2023 |
| UK Crispy Chicken Ltd | Hospitality | 2026 |