| Tysr Limited | Wholesale & retail | 2019 |
| U & I Trading Services Limited | Professional & scientific | 2013 |
| U Catering Group Ltd | Hospitality | 2019 |
| UA UK Delivery Ltd | Transport & logistics | 2026 |
| UA1988 Ltd | Professional & scientific | 2019 |
| UAA Fish Limited | Hospitality | 2020 |
| Uber AI Ltd | Manufacturing | 2023 |
| Ubiq Digital Partners Ltd | Information & communication | 1991 |
| Ucpro Investments Limited | Real estate | 2015 |
| Ucpro Limited | Information & communication | 2019 |
| UCS (NW) Ltd | Construction | 2023 |
| UG Healthcare Limited | Health & social care | 2019 |
| Uheat Services Limited | Construction | 2018 |
| UIG Projects Ltd | Professional & scientific | 2016 |
| UK Bunded Fuel Tanks Ltd | Extraterritorial | 2008 |
| UK Electrical & Data Installations Limited | Construction | 2022 |
| UK Freight & Logistics Ltd | Transport & logistics | 2020 |
| UK Industrial Control Systems Ltd | Administrative & support | 2019 |
| UK Robotics Ltd | Manufacturing | 2007 |
| UK Skin MED Ltd | Wholesale & retail | 2026 |
| UK Sports Management Limited | Professional & scientific | 2018 |
| UK Veterans Golf Association CIC | Other services | 2025 |
| UKI Group Ltd | Professional & scientific | 2024 |
| UKI Mechanical Ltd | Construction | 2022 |
| UKI Print Ltd | Manufacturing | 2025 |
| UKI Site Operations Ltd | Construction | 2020 |
| Ulteum Ltd | Professional & scientific | 2021 |
| Ultimate Handyman Limited | Information & communication | 2006 |
| Ultimate Physique Personal Trainer Ltd | Health & social care | 2023 |
| Ultimate Projects Ltd | Construction | 2019 |
| Ultra Spikes Ltd | Wholesale & retail | 2025 |
| Ultraspec Medical Limited | Extraterritorial | 2013 |
| Umsa Communication Limited | Wholesale & retail | 2021 |
| UN1TY Network Ltd | Professional & scientific | 2025 |
| Uni-Clean (Enviromental) Ltd | Manufacturing | 2018 |
| Uni-Fire Protection Limited | Administrative & support | 2005 |
| Unicity United Kingdom Limited | Financial services | 2017 |
| Unicorn Creator Network Ltd | Information & communication | 2026 |
| Unicorn Developments Limited | Construction | 2018 |
| Unicorn Solutions Limited | Health & social care | 2015 |
| Unicorn Suites Asset Ltd | Construction | 2021 |
| Union Park, Jessop Court, Residents Management Company Limited | Households | 2026 |
| Union Park, Weston Court, Residents Management Company Limited | Households | 2026 |
| Unique Fire UK Ltd | Manufacturing | 2021 |
| Unique Nails & Beauty Limited | Other services | 2025 |
| Unique Trio Holdings Limited | Financial services | 2023 |
| United Fabrications Limited | Manufacturing | 2010 |
| Uniter Projects Ltd | Administrative & support | 2024 |
| Unitii Ltd | Manufacturing | 2017 |
| Unity Carers Private Limited | Health & social care | 2025 |
| Unity Facilities Ltd | Construction | 2024 |
| Unity Group Limited | Administrative & support | 2014 |
| Universal Contractors Limited | Administrative & support | 2024 |
| Universal Ground Care Limited | Administrative & support | 1997 |
| Unlocked Sacred Ltd | Administrative & support | 2023 |
| Untio Ltd | Professional & scientific | 2024 |
| UP North Timepieces Ltd | Wholesale & retail | 2026 |
| Upholstery Guru Ltd | Manufacturing | 2022 |
| Uprawr Network Ltd | Professional & scientific | 2025 |
| Upvc Kitchen Revival Ltd | Other services | 2000 |
| Upwards Agency Network Ltd | Professional & scientific | 2025 |
| UR Onyx Ltd | Health & social care | 2020 |
| Urban AGE Ltd | Construction | 2024 |
| Urban NU Ltd | Construction | 2017 |
| Urban Property Solutions North West Limited | Households | 2025 |
| Urban Spaces (NW) Limited | Construction | 2021 |
| Urbane Residential Roofing Ltd | Construction | 2009 |
| Urbane Roofing Limited | Construction | 2004 |
| Urbanlodge Limited | Hospitality | 2004 |
| Urmson LLP | | 2011 |
| US Three Properties Limited | Real estate | 2024 |
| USO Ltd | Hospitality | 2016 |
| USP Creations Limited | Administrative & support | 2016 |
| Utiligroup Acquisitions Limited | Professional & scientific | 2014 |
| Utiligroup Holdings Limited | Professional & scientific | 1998 |
| Utiligroup Limited | Professional & scientific | 2014 |
| Utiliserve Limited | Administrative & support | 2009 |
| Utilities Connect Ltd | Energy | 2015 |
| Utility Survey & Design Limited | Professional & scientific | 2023 |
| Utopian Industries Limited | Construction | 2024 |
| Uvbp Limited | Hospitality | 2026 |
| V & T Logistics Ltd | Transport & logistics | 2017 |
| V.A.B. Travel Limited | Administrative & support | 2003 |
| V360 Limited | Information & communication | 2003 |
| V4 Building & Design Ltd | Wholesale & retail | 2004 |
| VAL & RA Limited | Hospitality | 2019 |
| Vale Construction (Mc/R) Ltd | Construction | 2015 |
| Vale Narsche Limited | Financial services | 2023 |
| Valentin Amariei Ltd | Transport & logistics | 2023 |
| Valentis AI Labs Ltd | Information & communication | 2025 |
| Valiant Furniture Ltd | Manufacturing | 2020 |
| Valley Carpets Limited | Construction | 2018 |
| Value Beauty Ltd | Wholesale & retail | 2025 |
| Value Masks Ltd | Wholesale & retail | 2020 |
| Valvesafe Ltd | Professional & scientific | 2019 |
| Vamison Property Investment Ltd | Real estate | 2019 |
| Van Roof Rack Ltd | Wholesale & retail | 2020 |
| Vanguard Cleaning Management Solutions Limited | Administrative & support | 2002 |
| Vanguard CMS Holdings Limited | Financial services | 2020 |
| Vanilla Photography OR Design Ltd | Professional & scientific | 2007 |