| Tyren Transport Ltd | Transport & logistics | 2026 |
| TYRES4U Walsall Ltd | Wholesale & retail | 2016 |
| Tytan Tanning Studio Quinton Limited | Other services | 2023 |
| Tzsk First Ltd | Professional & scientific | 2020 |
| Tzsk Fourth Ltd | Hospitality | 2022 |
| Tzsk Second Ltd | Hospitality | 2021 |
| Tzsk Third Ltd | Hospitality | 2022 |
| U CAN Store IT Limited | Extraterritorial | 1975 |
| U K Made Group Limited | Wholesale & retail | 2016 |
| UA Management Services Limited | Professional & scientific | 2017 |
| UB75 Limited | Hospitality | 2025 |
| UBER1263 Limited | Transport & logistics | 2025 |
| Ubhi Property Group Ltd | Real estate | 2026 |
| Ubsidi Financial Limited | Information & communication | 2022 |
| Ubuntu Stem CIC | Education | 2025 |
| Ucgr Care Limited | Health & social care | 2024 |
| UDN Accountants Ltd | Professional & scientific | 2020 |
| UFC Shawarma Ltd | Hospitality | 2025 |
| Ufone Precision Engineers Limited | Manufacturing | 2001 |
| UHG Group Residential Limited | Health & social care | 2023 |
| UHM Logistics Limited | Real estate | 2023 |
| Uhpmc Ltd | Professional & scientific | 2014 |
| Uhuru Botanicals Ltd | Administrative & support | 2017 |
| UI Medical UK Limited | Wholesale & retail | 2020 |
| UIL Holding Ltd | Real estate | 2025 |
| Ujjan Limited | Health & social care | 2019 |
| Ujjan Properties Limited | Real estate | 2022 |
| UJP Distribution Limited | Wholesale & retail | 2025 |
| UK Best Carpets Ltd | Wholesale & retail | 2022 |
| UK Coach Tours Ltd | Transport & logistics | 2021 |
| UK Decorations Ltd | Wholesale & retail | 2024 |
| UK Direct Couriers Limited | Transport & logistics | 2003 |
| UK Electrical Installations (Midlands) Limited | Construction | 2002 |
| UK Flavour Fusion Ltd | Hospitality | 2025 |
| UK Hosted Provider Limited | Wholesale & retail | 2019 |
| UK Left Hand Drive Ltd | Wholesale & retail | 2021 |
| UK Life Medical Limited | Health & social care | 2024 |
| UK Lotus Centre Limited | Wholesale & retail | 2021 |
| UK Plumbing, Plastics and Bathrooms Ltd | Wholesale & retail | 2012 |
| UK School Badges Limited | Manufacturing | 2021 |
| UK Secure Shutters & Doors Ltd | Manufacturing | 2025 |
| UK Security and Events Limited | Administrative & support | 2010 |
| UK Site Welding Limited | Construction | 2007 |
| UK Telco Ltd | Administrative & support | 2009 |
| UK Thai Study Ltd | Education | 2019 |
| UK Tyre Group Ltd | Wholesale & retail | 2020 |
| UK Venture Property Ltd | Households | 2025 |
| Ukequitypartners Limited | Real estate | 2016 |
| Ukhippo Ltd | Real estate | 2025 |
| Ukis Services Ltd | Education | 2021 |
| Ukpk Consulting Ltd | Professional & scientific | 2023 |
| ULA1 Ltd | Real estate | 2023 |
| Ultima Build Limited | Real estate | 2021 |
| Ultimate Professionals Ltd | Administrative & support | 2015 |
| Ultra Host Pro Ltd | Information & communication | 2025 |
| Ultransportation Solution Ltd | Transport & logistics | 2025 |
| Ultrasound Pro Ltd | Health & social care | 2023 |
| Umarafashions Ltd | Wholesale & retail | 2024 |
| Umbrient Ltd | Information & communication | 2018 |
| Umfolkrem Ltd | Transport & logistics | 2024 |
| Umjizic Ltd | Transport & logistics | 2024 |
| UMR Consultancy Ltd | Professional & scientific | 2026 |
| Umrah Supermarket Walsall Ltd | Wholesale & retail | 2024 |
| Umrenzaer Ltd | Administrative & support | 2024 |
| UN1TY Fitness CIC | Health & social care | 2026 |
| Uncharted Restaurant and Lounge Ltd | Hospitality | 2026 |
| Unclebirdhead Games Ltd | Professional & scientific | 2025 |
| Underwater World (Midlands) Limited | Wholesale & retail | 2024 |
| Unemirtix Ltd | Administrative & support | 2024 |
| UNI Genie Ltd | Information & communication | 2017 |
| UNI YES OR NO Limited | Education | 2017 |
| Unibridge Education Limited | Education | 2024 |
| Unibuy Hub Limited | Wholesale & retail | 2025 |
| Uniclear Limited | Wholesale & retail | 2010 |
| Unico 3 Limited | Professional & scientific | 2010 |
| Unicores Limited | Professional & scientific | 1991 |
| Unified Associates CIC | Health & social care | 2026 |
| Union Community and Education Centre Ltd | Education | 2020 |
| Union Utilities Limited | Wholesale & retail | 2025 |
| Unique 1 Cleaning Services & Waste Management Ltd | Administrative & support | 2019 |
| Unique 1 Recruitment Limited | Administrative & support | 2024 |
| Unique Bar & Grill Ltd | Hospitality | 2022 |
| Unique Initiative Ltd | Transport & logistics | 2024 |
| Unique Jamaican Foodstore Ltd | Wholesale & retail | 2026 |
| Unique Solutions Central Limited | Administrative & support | 2013 |
| Unique Solutions Direct Limited | Wholesale & retail | 2011 |
| Unique Tastybuds and Events Limited | Hospitality | 2022 |
| Unique Triad Limited | Hospitality | 2017 |
| Unisson Properties Ltd | Real estate | 2024 |
| Unit Design Limited | Manufacturing | 1987 |
| United 4EVER Software Limited | Information & communication | 2025 |
| United Cars(Uk) Ltd | Transport & logistics | 2015 |
| United Glass Group Ltd | Professional & scientific | 2012 |
| United Hospitality Ltd. | Hospitality | 2018 |
| United K Fixings Ltd | Wholesale & retail | 2021 |
| United Kingdom Sepsis Trust Limited | Health & social care | 2013 |
| United Support Group CIC | Public administration | 2017 |
| Unity Dist Holdings Limited | Real estate | 2025 |
| Unity Distribution Ltd | Wholesale & retail | 2014 |
| Unity Health Limited | Health & social care | 2022 |