| Umiya Construction Services Ltd | Construction | 2026 |
| Umma's Kitchen Ltd | Hospitality | 2022 |
| Umoja Staffing Solutions Limited | Administrative & support | 2026 |
| UNA Property Consultancy Limited | Real estate | 2014 |
| Unafraid Life Limited | Information & communication | 2021 |
| Unami Sushi Limited | Wholesale & retail | 2025 |
| Unboxxed Ltd | Wholesale & retail | 2025 |
| Uncle Builder Limited | Construction | 2019 |
| Undermywing Ltd | Education | 2024 |
| Unequalled Construction Limited | Construction | 2020 |
| Unexpected Avenues Limited | Arts & recreation | 2021 |
| Ungar& Ungar Limited | Wholesale & retail | 2002 |
| UNI Admit Ltd | Information & communication | 2026 |
| UNI Agent Ltd | Education | 2021 |
| UNI Drive in Ltd | Real estate | 2017 |
| UNI Offer Ltd | Education | 2021 |
| Unibud International Ltd. | Manufacturing | 1992 |
| Unic Assets Ltd | Construction | 2019 |
| Unico Property Holdings Ltd | Real estate | 2025 |
| Unicorn Accessories Limited | Wholesale & retail | 2020 |
| Unicorn Construction Ltd | Wholesale & retail | 2018 |
| Unicraft Limited | Construction | 2009 |
| Unified Credit Solutions Ltd | Information & communication | 2013 |
| Unified Global Solutions Ltd. | Wholesale & retail | 2020 |
| Unifier Technologies Ltd | Information & communication | 2020 |
| Unifique Ltd | Professional & scientific | 2023 |
| Uniforms & Sportswear Distributors Limited | Wholesale & retail | 1990 |
| Uniglo Real Estate Ltd | Real estate | 2025 |
| Uniguard Limited | Professional & scientific | 2014 |
| Unihart Properties Limited | Real estate | 1988 |
| Unik Store Ltd | Wholesale & retail | 2025 |
| Unikin Technologies Limited | Information & communication | 2020 |
| Unilead Global Solutions Ltd | Wholesale & retail | 2025 |
| Unileaf Ventures Limited | Wholesale & retail | 2025 |
| Unilinqs Limited | Wholesale & retail | 2018 |
| Unimaxx Global Services Ltd | Wholesale & retail | 2025 |
| Unimore Products (UK) Limited | Professional & scientific | 2014 |
| Union Auto Traders Limited | Wholesale & retail | 2025 |
| Union Point Limited | Construction | 2021 |
| Union Tours Limited | Administrative & support | 2004 |
| Uniq Care & Support Ltd | Administrative & support | 2009 |
| Uniq Dental Limited | Health & social care | 2022 |
| Uniq Electrical Services Ltd | Construction | 2021 |
| Unique Drainage Solutions Limited | Construction | 2019 |
| Unique Gelato Ltd | Hospitality | 2020 |
| Unique Hair and Beauty Ltd | Other services | 2026 |
| Unique Holdco Ltd | Financial services | 2025 |
| Unique House Limited | Wholesale & retail | 2021 |
| Unique Label International Private Limited | Wholesale & retail | 2025 |
| Unique Look Construction Ltd | Construction | 2024 |
| Unique Metal Design Limited | Wholesale & retail | 1999 |
| Unique Tunes Raga Connect Ltd | Arts & recreation | 2025 |
| Unique Valeting Limited | Administrative & support | 1999 |
| Unique Wellness Solutions Limited | Professional & scientific | 2014 |
| Unique Wholesale Limited | Wholesale & retail | 2025 |
| Unique Windows Doors & Conservatories Limited | Construction | 2006 |
| UNIQUE2CARE Ltd. | Health & social care | 2016 |
| Unisco Investments Ltd | Real estate | 2023 |
| Unisco Limited | Construction | 2005 |
| UNIT3D Property Partners Ltd | Real estate | 2026 |
| Unitech IT Solutions Limited | Information & communication | 2018 |
| Unitech IT Systems Ltd | Information & communication | 2026 |
| United Beauty Solutions Limited | Wholesale & retail | 2021 |
| United Brothers 24 Ltd | Construction | 2024 |
| United Business Solutions USA Limited | Information & communication | 2024 |
| United Cargo Services Limited | Transport & logistics | 2002 |
| United Digambar Jain Community UK Ltd | Other services | 2026 |
| United Export Services UK Ltd | Information & communication | 2013 |
| United Fine Arts Academy (London) Limited | Education | 2014 |
| United Health Limited | Professional & scientific | 2024 |
| United Homes Group Ltd | Health & social care | 2020 |
| United Immigration Limited | Professional & scientific | 2025 |
| United Industrial Services Ltd. | Manufacturing | 2003 |
| United Jets Limited | Other services | 2023 |
| United Kingdom Transfers Ltd | Transport & logistics | 2017 |
| United Money Services Ltd | Financial services | 2016 |
| United Muslim Ummah Limited | Other services | 2018 |
| United Shoretravel Limited | Transport & logistics | 2010 |
| United Swallows Limited | Financial services | 2021 |
| United Tech Services Limited | Professional & scientific | 2018 |
| Unitworks Limited | Information & communication | 2019 |
| Unity Assets Limited | Real estate | 2026 |
| Unity Automotive Engineering & Design Ltd | Wholesale & retail | 2018 |
| Unity Consulting and Trading Co. Ltd | Professional & scientific | 2023 |
| Unity Fire Safety Limited | Construction | 2020 |
| Unity Foster Care Limited | Health & social care | 2015 |
| Unity Governance Limited | Professional & scientific | 2026 |
| Unity Supplies Limited | Real estate | 1996 |
| Unity Ventures Holistic (I AM One) Ltd | Other services | 2019 |
| Unitysuite Ltd | Wholesale & retail | 2026 |
| Univag Limited | Real estate | 1983 |
| Univation-Sa Ltd | Wholesale & retail | 2022 |
| Universal a+ Limited | Education | 2005 |
| Universal Akseer Services Ltd | Administrative & support | 2026 |
| Universal Consultech Ltd | Information & communication | 2023 |
| Universal Culture Limited | Arts & recreation | 2000 |
| Universal Delivery Solutions Limited | Transport & logistics | 2008 |
| Universal Heating & Plumbing Limited | Construction | 2003 |
| Universal Holistic Practitioners Community Ltd | Health & social care | 2025 |
| Universal Interiors (UK) Limited | Construction | 2005 |