| UBM5PROPERTIES Ltd | Construction | 2025 |
| UCV Limited | Construction | 2025 |
| UG Ltd | Wholesale & retail | 2025 |
| UK Chinese (Ying-Hua) Table Tennis Club Ltd | Arts & recreation | 2016 |
| UK Chinese Ying-Hua Education Centre Ltd | Education | 2025 |
| UK Deaf Sport | Arts & recreation | 2013 |
| UK Eco Projects Ltd | Professional & scientific | 2025 |
| UK Grooming Room Ltd | Other services | 2018 |
| UK Print and Promotions Ltd | Arts & recreation | 2009 |
| UK Saif Ltd | Transport & logistics | 2025 |
| UK Tianjin Chinese Association | Extraterritorial | 2014 |
| UK Tianjin Chinese Business Association | Extraterritorial | 2014 |
| Ukguests.Com Limited | Real estate | 2005 |
| UKI Storage Solutions Ltd | Construction | 2009 |
| UKM Films Ltd | Information & communication | 2016 |
| Ukos Design & Build Limited | Construction | 2023 |
| Ukos Direct Ltd | Wholesale & retail | 2026 |
| Ukos Group Limited | Financial services | 2023 |
| Ukos Ltd | Wholesale & retail | 2000 |
| Ukos Property Limited | Real estate | 2023 |
| Ultra Cold AC Limited | Wholesale & retail | 2026 |
| Ultra Security Solutions Ltd | Administrative & support | 2022 |
| Ultra Sharp Films Ltd | Information & communication | 2017 |
| Uncle City Ltd | Transport & logistics | 2024 |
| Under 23 Limited | Information & communication | 2019 |
| Unebun Ltd | Other services | 2022 |
| Uni-Fronts Limited | Construction | 1968 |
| Union Brands Collection Limited | Hospitality | 2022 |
| Union Coffee and Dough Limited | Hospitality | 2023 |
| Union Electric Vehicle Charging Limited | Professional & scientific | 2024 |
| Unioncrest Capital Limited | Professional & scientific | 2025 |
| Unique Cars Limited | Transport & logistics | 2007 |
| Unique Home School Limited | Education | 2023 |
| Unique Tennis Langley Ltd | Arts & recreation | 2025 |
| Unisolve Properties Limited | Real estate | 2015 |
| Unisolve Services Limited | Information & communication | 2005 |
| United First Light Productions Limited | Information & communication | 2014 |
| United KAB Co Limited | Transport & logistics | 2003 |
| United Kingdom OIL Pipelines Limited | Professional & scientific | 1963 |
| United Krav Maga Force Limited | Education | 2018 |
| United Strategic Metals Ltd | Professional & scientific | 2025 |
| Unity Asphalt Company (London) Limited | Real estate | 1947 |
| Unity IT Software Limited | Wholesale & retail | 2023 |
| Universal Clutches Limited | Manufacturing | 2019 |
| Unknown Communications Ltd | Professional & scientific | 2026 |
| UNLIMIT3D Ltd | Manufacturing | 2023 |
| UNQ Villas Collection Ltd | Real estate | 2024 |
| Unread Productions Ltd | Professional & scientific | 2010 |
| Unybrands Operations Ltd | Professional & scientific | 2020 |
| Unyk Solutions Ltd | Administrative & support | 2025 |
| UP Digital Marketing & Business Services Ltd | Professional & scientific | 2023 |
| Up-Stir Collection Ltd | Wholesale & retail | 2022 |
| Uplay Sports CIC | Education | 2022 |
| Uplay Venues Ltd | Administrative & support | 2020 |
| Uppa Ltd | Hospitality | 2025 |
| Uppercut Barber Ltd | Other services | 2025 |
| Upson Noble Binders Limited | Manufacturing | 2014 |
| Upson Noble Press Limited | Manufacturing | 2009 |
| Uptown Chauffeurs Ltd | Transport & logistics | 2021 |
| Uranda Group Ltd | Information & communication | 2022 |
| Urban Electric Networks Ltd | Manufacturing | 2017 |
| Urban Torque Ltd | Wholesale & retail | 2025 |
| Urjaa Limited | Real estate | 2003 |
| Urnamai Ltd | Information & communication | 2025 |
| US Vitta Ltd | Administrative & support | 2025 |
| USA Nails TD Ltd | Other services | 2023 |
| Usafi Cleaning Services Ltd | Administrative & support | 2018 |
| USB Media Limited | Wholesale & retail | 2006 |
| Utopia Signs Limited | Professional & scientific | 1995 |
| UV Cured Ltd | Manufacturing | 2022 |
| UV Interiors Ltd | Construction | 2021 |
| Uxbridge Snow Foam Limited | Other services | 2025 |
| V G Merchants Limited | Wholesale & retail | 2025 |
| V M Berridge Builders Ltd | Construction | 2015 |
| V P Building Contractor Ltd | Construction | 2019 |
| V Squared Properties Limited | Real estate | 2019 |
| V Thaker Limited | Wholesale & retail | 2015 |
| V-Flatroofing Ltd | Construction | 2024 |
| V-Squared Properties (Holdings) Limited | Financial services | 2023 |
| V.Gan Limited | Wholesale & retail | 2018 |
| V5G Solution Limited | Administrative & support | 2015 |
| Vaboo Limited | Hospitality | 2015 |
| VAD Construction Ltd | Construction | 2020 |
| Vaga Media Ltd | Information & communication | 2017 |
| Vale Farm Management Company Limited | Households | 2008 |
| Valentindrive Ltd | Transport & logistics | 2024 |
| Valere Capital Ltd | Construction | 2025 |
| Valravn Ltd | Manufacturing | 2025 |
| Valtertrans Ltd | Administrative & support | 2017 |
| Value Landscapes Limited | Construction | 2013 |
| Valy Plumbing Ltd | Construction | 2021 |
| Van MAN NOW Ltd | Transport & logistics | 2014 |
| Vanaddics Ltd | Manufacturing | 2026 |
| Vanea Construction Ltd | Construction | 2021 |
| Vanessa Dainty Limited | Professional & scientific | 2014 |
| Vango Limited | Transport & logistics | 2022 |
| Vania Limited | Administrative & support | 2007 |
| Vanity H & B Salon Ltd | Other services | 2019 |
| Vanpool Services Ltd | Transport & logistics | 2012 |
| Vantage Diagnostics Ltd | Administrative & support | 2006 |