| TJS Total Joinery Solutions Ltd | Construction | 2020 |
| TL Pallets Limited | Manufacturing | 2025 |
| TM Renewables Ltd | Construction | 2026 |
| TM Tronix Ltd | Wholesale & retail | 2018 |
| TMI Potter Limited | Real estate | 2021 |
| TO Consulting Engineers Ltd | Professional & scientific | 2024 |
| Toast Pet Ltd | Wholesale & retail | 2025 |
| Token Works Ltd | Wholesale & retail | 2025 |
| Tolleys Tack Limited | Other services | 2014 |
| Tomaro Bros. Ltd | Information & communication | 2023 |
| Tomlinson & Smith Limited | Construction | 1930 |
| Tomsen Ltd | Wholesale & retail | 2023 |
| Top Fade (Langold) Ltd | Other services | 2022 |
| Top G Education Ltd | Education | 2022 |
| Top Locks Limited | Other services | 2003 |
| Topioneer Care Limited | Health & social care | 2023 |
| Total Dog Daycare Ltd | Other services | 2023 |
| Total Dog Grooming Ltd | Other services | 2023 |
| Total Dog Training & Behaviour Ltd | Other services | 2024 |
| Total Logistics Solutions Ltd | Professional & scientific | 2025 |
| Total Property Solutions 86 Ltd | Construction | 2025 |
| Tournament Holdings Limited | Arts & recreation | 2016 |
| Tower Air Movement (Contracts) Ltd | Construction | 2010 |
| Track Technology Limited | Financial services | 1958 |
| Trackside Civils Ltd | Construction | 2024 |
| Trackside Management Limited | Professional & scientific | 2025 |
| Trackside Management M Limited | Professional & scientific | 2025 |
| Traffic Light Graphics Ltd | Manufacturing | 2022 |
| Training Education Services Limited | Professional & scientific | 2003 |
| Trainright Limited | Other services | 2011 |
| Transform Training Ltd | Health & social care | 2014 |
| Transit Titans Ltd | Transport & logistics | 2025 |
| Translyn Limited | Transport & logistics | 2021 |
| Travis LEE Commercials Ltd | Wholesale & retail | 2024 |
| Trawlsound Limited | Construction | 1981 |
| Trenam Engineering Limited | Mining & quarrying | 2021 |
| Tribe Engineering Limited | Professional & scientific | 2011 |
| Trinity Comfort Assets Limited | Real estate | 2026 |
| Truckland Ltd | Transport & logistics | 2018 |
| Truestyle Windows and Property Repairs Ltd | Construction | 2011 |
| Trust by Benchmark Limited | Construction | 2024 |
| Trustee & Probate Services Ltd | Professional & scientific | 2019 |
| Trustseal Limited | Construction | 1995 |
| Trustseal Property Holdings Limited | Real estate | 2023 |
| TS4 Limited | Real estate | 2013 |
| TSL Retailers Ltd | Wholesale & retail | 2018 |
| Ttmcadsolutions Ltd | Professional & scientific | 2026 |
| Ttrl Financial Planning Ltd | Professional & scientific | 2020 |
| Tubbytech Partners Ltd | Information & communication | 2021 |
| Turner & Wilson (Whitwell) Limited | Construction | 2002 |
| Turner and Walker Ltd | Manufacturing | 2019 |
| TVK Wholesale Ltd | Wholesale & retail | 2025 |
| Twins FD Ltd | Hospitality | 2020 |
| Two Teachers Ltd | Education | 2020 |
| TYH Consulting Ltd | Wholesale & retail | 2024 |
| Ugly Duckling Interiors Limited | Other services | 2013 |
| UK Luca-S Ltd | Wholesale & retail | 2021 |
| UK Security Nation Ltd | Administrative & support | 2025 |
| UK Smart Energy Ltd | Extraterritorial | 2021 |
| UK1 Trading Ltd | Wholesale & retail | 2012 |
| Ukey Consulting & Publishing Ltd | Wholesale & retail | 2020 |
| Ukgrassrootsshow Ltd | Administrative & support | 2025 |
| Ukot IEX Ltd | Manufacturing | 2013 |
| UKT Services Limited | Professional & scientific | 2017 |
| Uniconsystems Ltd | Manufacturing | 2018 |
| Uniq (Holdings) Limited | Financial services | 1959 |
| Uniq Limited | Financial services | 2000 |
| Unique KB Ltd | Construction | 2022 |
| Unique Kitchens & Bathrooms Ltd | Construction | 2019 |
| Unique Software Solutions Limited | Information & communication | 2003 |
| Unique Tables Ltd | Manufacturing | 2014 |
| Upandunda Limited | Construction | 2014 |
| Urban Clay Limited | Real estate | 2010 |
| Urban Nest Rentals Limited | Real estate | 2024 |
| USS Holdings Limited | Financial services | 2024 |
| V&V Property Solutions Ltd | Real estate | 2025 |
| Vanclaron CIC | Health & social care | 2019 |
| Vanguard Property Sourcing Limited | Real estate | 2025 |
| Vapes 4 UK Ltd | Wholesale & retail | 2024 |
| VAPESHOP2024 Limited | Wholesale & retail | 2024 |
| VCS Driver Training Ltd | Education | 2026 |
| VEN Mccaul & Associates Ltd | Administrative & support | 2018 |
| Ventec Services Ltd | Construction | 2008 |
| Venus Bathroom Studio Ltd. | Administrative & support | 2002 |
| Venus Xpress Ltd | Transport & logistics | 2017 |
| Verification International Limited | Professional & scientific | 2010 |
| Vertex Fire Specialists Limited | Other services | 2026 |
| VIBE2024 Limited | Hospitality | 2024 |
| Vibesco Ltd | Wholesale & retail | 2023 |
| Vinetree Media Solutions Limited | Arts & recreation | 2019 |
| Vintage Skunkworks LLP | | 2009 |
| Virum TCG Ltd | Wholesale & retail | 2026 |
| Vision Campervans Ltd | Wholesale & retail | 2024 |
| Vision Canvassing Ltd | Administrative & support | 2019 |
| Vision Traffic Management Solutions Limited | Information & communication | 2022 |
| Vivos Retail Holdings Limited | Financial services | 2021 |
| Vlaxmi Ltd | Real estate | 2025 |
| Voldi Ltd | Wholesale & retail | 2017 |
| VTX Performance Coaching Limited | Health & social care | 2025 |
| Vulcan AI Ltd | Information & communication | 2025 |