| Ultimate Support Services Limited | Information & communication | 2023 |
| Ulva Company Limited | Real estate | 2025 |
| UMC Construction Ltd | Construction | 2020 |
| UMC Grand Homes Ltd | Construction | 2023 |
| UMD International Ltd | Information & communication | 2019 |
| Unapologetic Cocktails Ltd | Manufacturing | 2025 |
| Uncoiled Ltd | Information & communication | 2024 |
| Underbridge Platform Rentals Limited | Administrative & support | 2021 |
| Undercutter Limited | Administrative & support | 2008 |
| Unfold Stories Ltd | Information & communication | 2017 |
| UNI School of Motoring Ltd | Education | 2024 |
| Uni'D Wheels Ltd | Wholesale & retail | 2024 |
| Unique Investment Properties Limited | Real estate | 2010 |
| Unique Lifestyle Estates Ltd | Wholesale & retail | 2024 |
| Unique Spices & Herbs Ltd | Wholesale & retail | 2019 |
| Unique Training Solutions Limited | Education | 2003 |
| Unit 4 the Chilterns Building Management Company Limited | Real estate | 2009 |
| Unit Productions Limited | Transport & logistics | 2025 |
| Unitary Ltd | Information & communication | 2019 |
| Unite Insights Ltd | Information & communication | 2025 |
| United Containers Limited | Manufacturing | 2025 |
| United Herts Limited | Wholesale & retail | 2016 |
| Universal Aircraft Sales and Management Ltd | Professional & scientific | 2026 |
| Universal Lawnmowers Limited | Wholesale & retail | 2012 |
| Universal Shield Agency Ltd | Information & communication | 2025 |
| Unlimited Design Solutions Ltd | Wholesale & retail | 2022 |
| Unplugged Early Years Limited | Information & communication | 2025 |
| Unrealised Limited | Professional & scientific | 2024 |
| UP Tutoring Ltd | Professional & scientific | 2019 |
| Upbeat Wellness Limited | Manufacturing | 2023 |
| Upfish Business Services Ltd | Real estate | 2010 |
| Upgrade Accounting Ltd | Professional & scientific | 2019 |
| Uplay Sports Management Ltd. | Education | 2012 |
| Upper Lattimore Road Management Company Limited | Households | 1981 |
| Upscale Marketing Agency Ltd | Professional & scientific | 2014 |
| Upside CS Ltd | Professional & scientific | 2026 |
| Upsolve Labs UK Limited | Information & communication | 2023 |
| Urban Potential Ltd | Real estate | 2018 |
| Urban Saints Attire Ltd | Wholesale & retail | 2025 |
| Urbanissta Ltd | Professional & scientific | 2010 |
| Urben Technologies Holdings Limited | Financial services | 2022 |
| Urben Technologies Limited | Information & communication | 2015 |
| Ureka Ltd | Information & communication | 2022 |
| US Binance Fintech SPV LLP | | 2022 |
| Usips Ltd | Construction | 2022 |
| Uskuri Interiors Ltd | Other services | 2025 |
| Uskuri Ltd | Professional & scientific | 2026 |
| UTC Transport Consultants Limited | Professional & scientific | 2011 |
| Utopia Ecommerce Limited | Professional & scientific | 2022 |
| UYM Herts Ltd | Hospitality | 2025 |
| V a Capital Partners LLP | | 2023 |
| V Douglas Consulting Limited | Professional & scientific | 2024 |
| V Hotel Glasgow Limited | Hospitality | 2021 |
| V&N Real Estates Limited | Real estate | 2022 |
| V&Nglobal Limited | Transport & logistics | 2020 |
| V25 Ltd | Wholesale & retail | 2005 |
| V3RGE Limited | Information & communication | 2025 |
| V8TPR Ltd | Manufacturing | 2022 |
| Vache Bleue Galleries Ltd | Wholesale & retail | 2019 |
| Vaiia Ltd | Information & communication | 2021 |
| VAL Trade Hungari KFT Ltd | Wholesale & retail | 2026 |
| Vale Estates Limited | Real estate | 1994 |
| Valeria Transport Ltd | Transport & logistics | 2025 |
| Valetti Ltd | Wholesale & retail | 2025 |
| Valiantstudios Ltd | Information & communication | 2025 |
| Valley Supply Solutions Limited | Wholesale & retail | 2024 |
| Value Beyond Savings Limited | Professional & scientific | 2017 |
| Valuing Minds Ltd. | Professional & scientific | 2016 |
| Vamp Assist Ltd | Administrative & support | 2021 |
| Vampire Records Limited | Information & communication | 1999 |
| Van Blerk Design Ltd | Other services | 2012 |
| Vanilla Crest Limited | Information & communication | 2020 |
| Vanilr Ltd | Information & communication | 2016 |
| Vanquish Capital Ltd | Administrative & support | 2022 |
| Vantage Chain Advisory Limited | Information & communication | 2026 |
| Vantage Tech Holdings Limited | Information & communication | 2024 |
| Vape Session Ltd | Wholesale & retail | 2025 |
| Vassell's Commercial & Domestic Engineers Ltd. | Construction | 2014 |
| Vatopedi Transport Ltd | Transport & logistics | 2026 |
| Vauban Global Nominees Limited | Financial services | 2022 |
| Vauban Poliorcetics LLP | | 2019 |
| Vauban Technologies Limited | Information & communication | 2018 |
| VB Associates Limited | Administrative & support | 2007 |
| VBC23 Ltd | Wholesale & retail | 2024 |
| VDG Trading Ltd | Hospitality | 2024 |
| Veavia Limited | Manufacturing | 2025 |
| Vecopharm Limited | Professional & scientific | 2013 |
| Veeda Limited | Hospitality | 2013 |
| Veedence Limited | Information & communication | 2011 |
| Vega Link (UK) Limited | Administrative & support | 2002 |
| Veggie Mania Limited | Manufacturing | 2024 |
| Vehicle AI Limited | Information & communication | 2025 |
| Vektor Partners SIDECAR1 LLP | | 2020 |
| Vektor Partners SIDECAR2 LLP | | 2021 |
| Velaro Trading Ltd | Wholesale & retail | 2026 |
| Velo Property Management Ltd | Real estate | 2024 |
| Velocity Co-Invest LLP | | 2024 |
| Velocity Network Services Ltd | Information & communication | 2025 |
| Velocity Vintage Drags Ltd | Administrative & support | 2025 |
| Velsys Limited | Information & communication | 2009 |