| Tssa Cars Limited | Administrative & support | 2010 |
| Tuffy Limited | Wholesale & retail | 2025 |
| Tulja Fruit & VEG Ltd | Wholesale & retail | 2025 |
| Tulsi & Bhek Home Ltd | Real estate | 2024 |
| Tulsi Hair & Beauty Parlour Limited | Other services | 2017 |
| Tummies Slough Ltd | Hospitality | 2019 |
| Tune Chemical Tankers (UK) Limited | Administrative & support | 2017 |
| Turban Tones Ltd | Arts & recreation | 2022 |
| Turcanu R&O Ltd | Transport & logistics | 2024 |
| Turkish Takeaway Limited | Hospitality | 2025 |
| Turn IT UP Productions Limited | Information & communication | 2009 |
| Turner & Lally Properties Ltd | Real estate | 2025 |
| Turning Point Educational Services Ltd | Education | 2010 |
| Tuscany Group Limited | Wholesale & retail | 2024 |
| Tuteck Technologies Private Limited | Information & communication | 2020 |
| Tutorie Limited | Education | 2024 |
| Tutum Workplace Ltd | Professional & scientific | 2020 |
| TVK Associates Ltd | Administrative & support | 2026 |
| TW Fintech Ltd | Financial services | 2023 |
| Twelfth House Publicity Ltd | Professional & scientific | 2025 |
| Twelver Properties Ltd | Real estate | 2020 |
| Twenty One Associates Ltd | Construction | 2026 |
| Twentyfour Thirtysix Ltd | Information & communication | 2021 |
| Twentytwointeriors London Ltd | Construction | 2021 |
| Twice TOO Ltd | Wholesale & retail | 2026 |
| Twin Bees Ltd | Professional & scientific | 2023 |
| Twin Tech Limited | Information & communication | 2017 |
| Twinkle RAJ Ltd | Wholesale & retail | 2025 |
| Twinkle Stars Nursery School Ltd | Education | 2019 |
| Twinstar (UK) Limited | Wholesale & retail | 2009 |
| Two Brothers Innovation Ltd | Manufacturing | 2024 |
| Two Seas Holdings Ltd | Real estate | 2021 |
| Twoseventwo Studio Limited | Professional & scientific | 2024 |
| Twrtradings Ltd | Real estate | 2021 |
| TY Medical Limited | Health & social care | 2014 |
| TY Track Ltd | Construction | 2025 |
| Tyamen Limited | Professional & scientific | 1993 |
| Tyda Interiors Ltd | Construction | 2022 |
| Tyleo Investments Ltd | Real estate | 2021 |
| Tylerstanleymedia Ltd | Professional & scientific | 2023 |
| Tyreapp Ltd | Wholesale & retail | 2023 |
| Tyresport Limited | Wholesale & retail | 2025 |
| Tzar Labs UK Private Limited | Professional & scientific | 2024 |
| U and H Assets Ltd | Real estate | 2023 |
| U LET Rooms Ltd | Real estate | 2018 |
| U R Data Consultancy Limited | Information & communication | 2014 |
| U W Homes Ltd | Real estate | 2022 |
| U&Z Delivery Services Ltd | Other services | 2023 |
| U2M2 Ltd | Wholesale & retail | 2023 |
| UA Manchester Ltd | Extraterritorial | 2017 |
| UA Wembley Ltd | Extraterritorial | 2017 |
| UAP Trading Limited | Wholesale & retail | 2017 |
| UB Holdings UK- Ltd | Wholesale & retail | 2018 |
| UBC Accountant Ltd | Professional & scientific | 2012 |
| Ubella Limited | Manufacturing | 2025 |
| Ubnd Ltd | Construction | 2025 |
| UBS Retail Holdings Ltd | Wholesale & retail | 2024 |
| UCC 1 Limited | Transport & logistics | 2018 |
| UCC 3 Limited | Transport & logistics | 2018 |
| UCC 5 Limited | Transport & logistics | 2018 |
| Ucfb Burnley Limited | Other services | 2018 |
| Ucfb College of Football Business Limited | Education | 2014 |
| Ucfb Education Limited | Education | 2011 |
| Ucfb HE Limited | Other services | 2019 |
| Ucfb Holdings Limited | Education | 2013 |
| Ucfb Liverpool Limited | Arts & recreation | 2018 |
| Ucfb London Stadium Limited | Other services | 2019 |
| Ucfb Manchester Academy Ltd | Extraterritorial | 2017 |
| Ucfb Manchester Limited | Arts & recreation | 2015 |
| Ucfb Online Limited | Other services | 2019 |
| Ucfb Student Accommodation Limited | Hospitality | 2011 |
| Ucfb Wembley Limited | Arts & recreation | 2012 |
| UCG Management Services Ltd | Professional & scientific | 2021 |
| UCL Aston Limited | Administrative & support | 2018 |
| UCL Springfield Limited | Administrative & support | 2018 |
| Ucmh Ltd | Other services | 2025 |
| Udai - United Designers of Architectural Intelligence Ltd | Professional & scientific | 2019 |
| Udiavi Solutions Ltd | Professional & scientific | 2025 |
| Udna Limited | Real estate | 2025 |
| Uestates Limited | Real estate | 2015 |
| UJH Group Ltd | Wholesale & retail | 2025 |
| UK & Ireland 2028 Limited | Arts & recreation | 2024 |
| UK Airports Travel Services Ltd | Transport & logistics | 2025 |
| UK AZ Properties Ltd | Real estate | 2023 |
| UK Berkshire Education Ltd | Education | 2024 |
| UK Best Electricals Ltd | Wholesale & retail | 2017 |
| UK Best Target Ltd | Wholesale & retail | 2020 |
| UK Car Services Centre Limited | Wholesale & retail | 2012 |
| UK China Association for International Talents Development | Education | 2023 |
| UK Chinese Tour Guide Association | Administrative & support | 2013 |
| UK Cool and Shopfitting Limited | Manufacturing | 2008 |
| UK Corporate Events Limited | Real estate | 2005 |
| UK Developers Ltd | Real estate | 2021 |
| UK Dosa Ltd | Hospitality | 2020 |
| UK Education Advisors Ltd | Education | 2023 |
| UK Emporium Ltd | Wholesale & retail | 2020 |
| UK Euro Transport Ltd | Other services | 2019 |
| UK Hire Ltd | Wholesale & retail | 2016 |
| UK Holistic Medicine and Treatment Centre Ltd | Health & social care | 2014 |
| UK Hostels Limited | Hospitality | 2004 |