| Trustitech Solutions Ltd | Information & communication | 2015 |
| TS Prime Residential Ltd | Real estate | 2026 |
| Tsquared Tiling Ltd | Other services | 2024 |
| TT Global Shipping Ltd | Transport & logistics | 2019 |
| TTR Global Ltd | Other services | 2026 |
| Tuba Connect Ltd | Professional & scientific | 2025 |
| Tudor Bank Limited | Health & social care | 2003 |
| Tulip Medicals Ltd | Health & social care | 2011 |
| Tulsi Enterprises Limited | Hospitality | 2002 |
| Turing Consulting Ltd | Professional & scientific | 2012 |
| Turmeric Kitchen Ltd | Hospitality | 2019 |
| Turquoise Kitchen (Pinner) Limited | Hospitality | 2018 |
| Tvisha Housing Ltd | Real estate | 2022 |
| Twaraa Technology & Services Ltd | Information & communication | 2021 |
| Tweak Facial Aesthetics Limited | Health & social care | 2017 |
| Twelfth August Ltd | Professional & scientific | 2019 |
| Twenty Four Eighty SIX Limited | Arts & recreation | 2005 |
| TWENTY8 Consulting Ltd | Professional & scientific | 2026 |
| Twickenham Hardware Ltd | Wholesale & retail | 2025 |
| Twiga Solis Group Limited | Hospitality | 2025 |
| Twistable Ltd | Professional & scientific | 2026 |
| Twisted Catering Ltd | Hospitality | 2023 |
| Twlhc Limited | Financial services | 2019 |
| Two Fingers Restaurants Ltd | Hospitality | 2017 |
| Two Little Bros Limited | Real estate | 2011 |
| Two Schillers Limited | Information & communication | 2012 |
| TY Investments Ltd | Real estate | 2012 |
| Tyas Properties Ltd | Real estate | 2023 |
| Tyfiant Property Limited | Professional & scientific | 2007 |
| Tym&D Limited | Health & social care | 2016 |
| Tyre Angels Ltd | Wholesale & retail | 2026 |
| Tysza Limited | Information & communication | 2021 |
| TZM Capital Limited | Financial services | 2025 |
| TZP Investments Limited | Financial services | 2025 |
| U&M E-Com Sales Limited | Wholesale & retail | 2018 |
| Udsm Services Limited | Manufacturing | 2020 |
| UG Consulting Ltd. | Professional & scientific | 2018 |
| UG Property Ltd | Real estate | 2021 |
| UJP Consulting Ltd | Information & communication | 2018 |
| UK Automap Ltd | Manufacturing | 2016 |
| UK Bespoke Property Ltd | Real estate | 2021 |
| UK Chapter Limited | Other services | 2016 |
| UK Construction Solutions Ltd | Construction | 2017 |
| UK Deliveries Services Ltd | Transport & logistics | 2021 |
| UK Legal Process Agents Limited | Professional & scientific | 2020 |
| UK NRI Services Limited | Administrative & support | 2024 |
| UK NRI Solutions Limited | Administrative & support | 2020 |
| UK Professional Services Corporation (Holdings) Ltd | Financial services | 2024 |
| UK Property Investors Ltd | Real estate | 2017 |
| UK Water Homes Ltd | Manufacturing | 2022 |
| UKO2MAP Ltd | Manufacturing | 2025 |
| Ukvo Ltd | Professional & scientific | 2021 |
| Ultimate Care Limited | Hospitality | 2006 |
| Ultimate Power Solutions Limited | Professional & scientific | 2000 |
| Ultrix Limited | Information & communication | 2020 |
| Umber Properties Limited | Hospitality | 2003 |
| Umbrella Mortgage Solutions Ltd | Financial services | 2016 |
| UNA Properties Ltd | Real estate | 2017 |
| Undefeated Queens Limited | Wholesale & retail | 2025 |
| Unicourt Finance Limited | Administrative & support | 2015 |
| Unicourt Milton Keynes Limited | Real estate | 2022 |
| Unicourt Properties Limited | Real estate | 1998 |
| Unicourt Wandsworth LLP | | 2007 |
| Uniqol Ltd | Manufacturing | 2023 |
| Unique Beauty Ltd | Other services | 2025 |
| Unique Gardens Ltd | Wholesale & retail | 2024 |
| Universal Distance Healing Limited | Health & social care | 2021 |
| Universal Fish Limited | Wholesale & retail | 2025 |
| Universal Technical Services Limited | Information & communication | 2019 |
| Universal Technology Systems Limited | Information & communication | 2011 |
| Universals Shipping (UK) Ltd. | Transport & logistics | 1998 |
| UNK International Limited | Wholesale & retail | 2024 |
| Unknown London Limited | Wholesale & retail | 2025 |
| Unmarkets Holdings Africa Limited | Financial services | 2025 |
| Untangle Strategy Ltd | Professional & scientific | 2019 |
| Untangle UK PVT Ltd | Information & communication | 2026 |
| UP Top Developments Limited | Construction | 2020 |
| Upsell Limited | Information & communication | 2015 |
| Upskillrx Ltd | Professional & scientific | 2023 |
| Urban Brickwork Solutions Ltd | Construction | 2026 |
| Urban Fleet & Securities Ltd | Administrative & support | 2026 |
| Urban Nest Investment Ltd | Real estate | 2021 |
| Urban Refrigeration & Shop Fitting Limited | Construction | 2009 |
| Urban Style Interiors Limited | Construction | 2021 |
| Urban Ville Limited | Wholesale & retail | 2021 |
| Uruzgym Ltd | Wholesale & retail | 2025 |
| Usman TIK Deals Ltd | Wholesale & retail | 2025 |
| UX DEN Ltd | Information & communication | 2023 |
| V & L Corporation Ltd | Health & social care | 2003 |
| V & R Builders (Brent) Limited | Construction | 1972 |
| V & R Homes Limited | Construction | 2002 |
| V & S Investments Limited | Real estate | 2016 |
| V & S Limited | Real estate | 2023 |
| V for Virtuoso Ltd | Manufacturing | 2019 |
| V J a Network Limited | Professional & scientific | 2022 |
| V N K R Ltd | Wholesale & retail | 2021 |
| V Ratnam & Co Limited | Health & social care | 2020 |
| V&P Logistics Ltd | Transport & logistics | 2020 |
| V-Square Holding Limited | Financial services | 2020 |
| V. Marsh Mushrooms & Salad Sales Limited | Wholesale & retail | 2010 |