| TTS Performance Parts Limited | Professional & scientific | 2005 |
| Ttsh Ltd | Financial services | 2021 |
| Ttxx Northampton Limited | Wholesale & retail | 2018 |
| Tucanu Transport Limited | Transport & logistics | 2015 |
| Tuckwell Domestic Buildings Ltd | Construction | 2022 |
| Tuco Services Ltd | Financial services | 2018 |
| Tudor Borta Ltd | Transport & logistics | 2016 |
| Tudor Freight Limited | Transport & logistics | 2024 |
| Tudor Manor Day Nursery Limited | Education | 2015 |
| Tudor Wood Limited | Construction | 2022 |
| Tuga's Home Ltd | Real estate | 2026 |
| Tumbuka Limited | Health & social care | 2022 |
| Tuned Music Ltd | Wholesale & retail | 2019 |
| Tuneera Ltd | Wholesale & retail | 2026 |
| Tunetables Ltd | Professional & scientific | 2024 |
| Tung Shing Delight Limited | Hospitality | 2026 |
| Tunibim Ltd | Transport & logistics | 2020 |
| Tunwell Mews Flats Management Limited | Households | 1989 |
| Turbo Technics Limited | Manufacturing | 1982 |
| Turc Logistic Transport Limited | Transport & logistics | 2022 |
| Turcan@Company Limited | Transport & logistics | 2014 |
| Turn 2 Classics Ltd | Wholesale & retail | 2019 |
| Turnberry Financial Planning Ltd | Financial services | 2006 |
| Turnberry Holding Ltd | Real estate | 2015 |
| Turnberry Portfolio Limited | Real estate | 2026 |
| Turnberry Properties (Midlands) Limited | Real estate | 2024 |
| Turnberry Property Management Ltd | Real estate | 2010 |
| Turner Tanks Limited | Construction | 2008 |
| Turners Farm Ltd | Agriculture & fishing | 2026 |
| Turnkey CNC Limited | Manufacturing | 2026 |
| Turtle Gate Property Limited | Real estate | 2024 |
| Turzo Limited | Transport & logistics | 2022 |
| Tusesal Ltd | Information & communication | 2026 |
| Tusker Rock Limited | Information & communication | 2002 |
| Tutu Cars Limited | Wholesale & retail | 2022 |
| Tutum Counselling Limited | Health & social care | 2024 |
| Tuudah & Sons Ltd | Health & social care | 2018 |
| Tuzik Limited | Transport & logistics | 2019 |
| TVV Express Solutions Ltd | Transport & logistics | 2024 |
| TW Interiors Limited | Construction | 2010 |
| TW Transport Limited | Transport & logistics | 2014 |
| TW54 Ltd | Wholesale & retail | 2024 |
| Twenty Eight Leisure Ltd | Hospitality | 2019 |
| Twenty TEN Developments Limited | Construction | 2010 |
| Twenty-Fifteen Engineering Limited | Manufacturing | 2015 |
| TWENTY8 Restaurants Limited | Hospitality | 2024 |
| TWHO19 Limited | Hospitality | 2019 |
| Twice (Milton Keynes) Ltd | Wholesale & retail | 2020 |
| Twickers Limited | Other services | 2011 |
| Twiga NET Solutions Ltd | Information & communication | 2022 |
| Twin Beeches Limited | Agriculture & fishing | 2023 |
| Twin Flag Ltd | Extraterritorial | 2021 |
| Twin Oaks Landscaping Ltd | Administrative & support | 2025 |
| Twin Peaks Bar and Restaurant Limited | Extraterritorial | 2023 |
| Twin Pine Developments Ltd | Real estate | 2016 |
| Twin Wholesale Limited | Wholesale & retail | 2007 |
| Twin-Track Consulting Ltd | Health & social care | 2014 |
| Twinkeys Property Limited | Real estate | 2025 |
| Twinkling Stars Care Ltd | Public administration | 2024 |
| Twins Brickwork Ltd | Construction | 2019 |
| Twist Consultancy Ltd | Professional & scientific | 2016 |
| Twisted Cork Limited | Wholesale & retail | 2023 |
| Twizll Ltd. | Administrative & support | 2018 |
| Twlm Ltd | Transport & logistics | 2026 |
| Two 28 Sarl Ltd | Professional & scientific | 2025 |
| Two Barns Ltd | Wholesale & retail | 2026 |
| Two Bros Restaurant Brands Limited | Hospitality | 2014 |
| Two Bru's Coffee Co. Ltd. | Hospitality | 2026 |
| Two Larches Ltd | Real estate | 2025 |
| Two Little Goats Limited | Administrative & support | 2006 |
| Two Wheels for Life Limited | Health & social care | 2016 |
| TWP Groundwork and Civil Engineering Contractors Ltd | Construction | 2019 |
| TWR Investors Ltd | Real estate | 2023 |
| Twum Ltd | Wholesale & retail | 2026 |
| TX Group Europe Ltd. | Wholesale & retail | 1991 |
| TX Perfect Ltd. | Information & communication | 2016 |
| Tyarya Limited | Manufacturing | 2002 |
| Tyarya Properties Limited | Real estate | 2020 |
| Tycadi Limited | Real estate | 2012 |
| Tye's UK Travel Ltd | Transport & logistics | 2025 |
| Tyler & Gallini’S Limited | Real estate | 2020 |
| Tylka Transport Ltd | Information & communication | 2012 |
| Type 21 Investments Limited | Real estate | 2026 |
| Type SB Ltd | Professional & scientific | 2026 |
| Typically Tina Ltd | Arts & recreation | 2020 |
| Tyre NOW Ltd | Professional & scientific | 2026 |
| Tyre Traxx Logistics Ltd | Transport & logistics | 2018 |
| Tyrego 24/7 Limited | Transport & logistics | 2022 |
| Tyres (Northampton) Limited | Wholesale & retail | 1983 |
| Tyres PIT Stop Ltd | Wholesale & retail | 2025 |
| Tyringham Care Limited | Health & social care | 2013 |
| Tyro CS Limited | Wholesale & retail | 2011 |
| TZA Limited | Professional & scientific | 1999 |
| TZB Construction Ltd | Construction | 2019 |
| U & W Stone Masonry Ltd | Construction | 2021 |
| U S Accountancy Services Ltd | Professional & scientific | 2015 |
| U-Can Marketing Ltd | Administrative & support | 2023 |
| U-Can Solutions Ltd | Administrative & support | 2023 |
| U-Nite Scaffolding Services Ltd | Construction | 2017 |
| U-Ukslp Community Interest Company | Education | 2010 |