| Unapologetically YOU Ltd | Other services | 2024 |
| Unbounded Internet Technology Ltd | Information & communication | 2026 |
| Unboundse Ltd | Manufacturing | 2026 |
| Unbreakables Group Ltd | Wholesale & retail | 2026 |
| Unchained Media Ltd | Wholesale & retail | 2025 |
| Uncle EJ Limited | Wholesale & retail | 2025 |
| Uncommon Labs Ltd | Information & communication | 2024 |
| Uneaca Trading Co., Ltd | Administrative & support | 2021 |
| Unearthing Ltd | Wholesale & retail | 2020 |
| Unfiltered Sporting Minds Ltd | Arts & recreation | 2024 |
| Unfurl Media Ltd | Information & communication | 2019 |
| Unicorn Magic Brew Limited | Hospitality | 2023 |
| Unicoursesuk Ltd | Education | 2024 |
| Unifaberry Ltd | Administrative & support | 2021 |
| Uniflex Systems Limited | Information & communication | 2026 |
| Unika Dance Events Ltd. | Arts & recreation | 2013 |
| Unikss Ltd | Information & communication | 2025 |
| Union Commercial Associates Limited | Professional & scientific | 2024 |
| Union Reach Ltd | Wholesale & retail | 2026 |
| Union Wardrobe Ltd | Wholesale & retail | 2024 |
| Unionchoice Retail Ltd | Wholesale & retail | 2026 |
| Unipufftech Limited | Wholesale & retail | 2023 |
| Uniq Marketing Ltd | Professional & scientific | 2025 |
| Uniqchem (UK) Co., Ltd | Administrative & support | 2011 |
| Unique Digital Business Ltd | Wholesale & retail | 2025 |
| Unique Plots Ltd | Real estate | 2020 |
| Unique Technology Ltd | Information & communication | 2025 |
| Uniqusy Ltd | Wholesale & retail | 2025 |
| Uniroute Exim Ltd | Wholesale & retail | 2025 |
| Unisell Global Ltd | Wholesale & retail | 2025 |
| United Agricultural Energy Limited | Manufacturing | 2025 |
| United and Thriving Co., Ltd | Extraterritorial | 2022 |
| United Engineering & Management Solutions Ltd | Professional & scientific | 2023 |
| United Kingdom Imperial Fine Art Academy Co., Ltd. | Extraterritorial | 2022 |
| United Risheng International PTE. Ltd. | Extraterritorial | 2018 |
| United Soles (UK) Ltd | Wholesale & retail | 2025 |
| United Technology Network Ltd | Wholesale & retail | 2023 |
| Unity Properties Service Ltd | Real estate | 2026 |
| Unity Workforce Solutions Limited | Administrative & support | 2026 |
| Universe Association | Professional & scientific | 2023 |
| Universe Unity Holdings Ltd | Real estate | 2021 |
| Uniwines (London) Ltd | Wholesale & retail | 2026 |
| Unlimited Union Ltd | Transport & logistics | 2025 |
| Unlock Luxury UK Ltd | Wholesale & retail | 2024 |
| Unova International Co., Ltd | Wholesale & retail | 2026 |
| Unreal Wargaming Studios Limited | Manufacturing | 2016 |
| Unsolicited Demos Records Ltd | Information & communication | 2026 |
| Untainted Hearts Ltd | Agriculture & fishing | 2021 |
| Untainted Limited | Manufacturing | 2019 |
| Untether Ltd | Information & communication | 2009 |
| Unum Diem Ltd | Arts & recreation | 2022 |
| Unuss Marketing Limited | Information & communication | 2022 |
| Unveil Ltd | Wholesale & retail | 2025 |
| UP Branding Ltd | Professional & scientific | 2018 |
| Upbeat Streamupbeat Stream Ltd | Wholesale & retail | 2025 |
| Updown Productions Ltd | Information & communication | 2025 |
| Upgrade People LLP | | 2022 |
| Upmart Store Limited | Wholesale & retail | 2026 |
| UPN Advisory Ltd | Information & communication | 2026 |
| Uprise Solutions Ltd | Education | 2016 |
| Upstream Network Ltd | Information & communication | 2022 |
| Urban Basic Ltd | Wholesale & retail | 2026 |
| Urban Bedouin Limited | Wholesale & retail | 2025 |
| Urban Cake Republic Limited | Wholesale & retail | 2017 |
| Urban Consultancy Ltd | Real estate | 2025 |
| Urban Elevation Group Ltd | Construction | 2025 |
| Urban Home Lettings Limited | Administrative & support | 2007 |
| Urban Thread Ltd | Wholesale & retail | 2025 |
| Urban Witch Ltd | Administrative & support | 2018 |
| Urbannest Commerce Ltd | Wholesale & retail | 2025 |
| Urbanpath Ltd | Wholesale & retail | 2026 |
| URC Webdesign Limited | Information & communication | 2024 |
| Urticad Tech Ltd | Wholesale & retail | 2025 |
| USA AEK Bearing Co., Ltd | Manufacturing | 2025 |
| USE Ability Ltd | Information & communication | 2021 |
| Useful and Practical Ideas Limited | Wholesale & retail | 2010 |
| Usefulthings Land Ltd | Wholesale & retail | 2023 |
| Usefulthings Ltd | Wholesale & retail | 2023 |
| USK Consulting Limited | Extraterritorial | 2013 |
| USK River Honey Ltd | Agriculture & fishing | 2025 |
| Usman Nika Ltd | Wholesale & retail | 2025 |
| Ustad Shani Ltd | Wholesale & retail | 2026 |
| Utopixel Ltd | Administrative & support | 2024 |
| Utrts Ltd | Information & communication | 2021 |
| Utyru Jghi Trading Limited | Wholesale & retail | 2025 |
| Uvesafe Limited | Professional & scientific | 2008 |
| Uwin Intl Co., Ltd | Extraterritorial | 2025 |
| Uygus Jakg Trading Limited | Wholesale & retail | 2025 |
| Uyxa Qqao Trading Limited | Wholesale & retail | 2025 |
| V and E Holdings Ltd | Hospitality | 2025 |
| V2B Distribution Ltd | Wholesale & retail | 2021 |
| V5 Integrated Industrial Solutions Ltd | Construction | 2026 |
| V7C Limited | Information & communication | 2013 |
| VA Tech Vision Ltd | Wholesale & retail | 2026 |
| Vaclue Property Limited | Construction | 2020 |
| Vadantia Limited | Financial services | 2017 |
| Vaelis Ltd | Wholesale & retail | 2025 |
| VAH Limited | Construction | 2023 |
| Vaillant (EUR) Ltd | Manufacturing | 2025 |
| Vaka Type Shyt Ltd | Wholesale & retail | 2025 |