| Truly Events Ltd | Administrative & support | 2018 |
| Trywines Expertise Limited | Wholesale & retail | 2003 |
| TSD Cost Services Ltd | Administrative & support | 2016 |
| Tsform Limited | Financial services | 2018 |
| Tslandscapes Limited | Administrative & support | 2018 |
| Tubney Warren Barns Properties Ltd | Real estate | 2026 |
| Tudor Court (Newbury) Limited | Households | 1967 |
| Tumbleweed Productions Limited | Hospitality | 2001 |
| Turaco Labs Limited | Information & communication | 2023 |
| Turbo Zeus Marketing Limited | Information & communication | 2024 |
| Turbostyle Coaches Limited | Transport & logistics | 1985 |
| Turkuaz Newbury Limited | Real estate | 2021 |
| Turner & Summersbee (Wessex) Ltd | Construction | 2026 |
| Turner and Summersbee Limited | Construction | 2003 |
| Turner Barratt Limited | Professional & scientific | 2010 |
| Turner Stone Holdings Limited | Financial services | 2016 |
| Tv-Bay Limited | Extraterritorial | 2024 |
| Tweak Consulting Ltd | Professional & scientific | 2025 |
| Twin Peak Services Ltd | Administrative & support | 2024 |
| Twinstar OPS Ltd | Other services | 2021 |
| Twisted Networks Ltd | Information & communication | 2019 |
| Twonicks QA Limited | Wholesale & retail | 2018 |
| TWP Engineering Services Ltd | Professional & scientific | 2021 |
| TWR Arrows Ltd | Professional & scientific | 2023 |
| TWR Performance Ltd | Manufacturing | 2020 |
| Twynham Tech Limited | Information & communication | 2022 |
| Twynings Limited | Administrative & support | 2007 |
| TY DA Group Ltd | Financial services | 2024 |
| TY DA Property Services Ltd | Hospitality | 2022 |
| Tyas Financial Solutions Ltd | Professional & scientific | 2021 |
| Tydevale Management Company Limited | Real estate | 2000 |
| Tymar Associates Limited | Professional & scientific | 2006 |
| Tyrrell Homes Limited | Real estate | 2008 |
| U-Stay Ltd | Other services | 2008 |
| U.K. Solenoid Limited | Extraterritorial | 2008 |
| U.K. Spares Limited | Extraterritorial | 1996 |
| Ubah Limited | Public administration | 2019 |
| UBT UK Division Limited | Professional & scientific | 2020 |
| UK Accounts Team Ltd | Information & communication | 2012 |
| UK Cables Limited | Wholesale & retail | 1993 |
| UK Components Limited | Extraterritorial | 2016 |
| UK Drives Limited | Extraterritorial | 1979 |
| UK Electric Limited | Wholesale & retail | 1992 |
| UK Material Handling Association Limited | Other services | 2020 |
| UK Metering Ltd | Extraterritorial | 2007 |
| UK Roasters Limited | Wholesale & retail | 2019 |
| UK Test Instruments Limited | Wholesale & retail | 1990 |
| UK-118-001 Limited | Real estate | 2021 |
| UK-118-002 Limited | Real estate | 2021 |
| UK-118-017 Limited | Real estate | 2021 |
| Ukbushcraft Ltd | Professional & scientific | 2021 |
| Ukfa Limited | Other services | 2025 |
| Ulajh Productions Ltd | Information & communication | 2023 |
| Ultimate Electrical Engineering Ltd | Other services | 2023 |
| Unique Vehicles Ltd | Wholesale & retail | 2021 |
| Unistrata Consulting Limited | Information & communication | 2007 |
| Unite Technology Ltd | Information & communication | 2017 |
| Unitech Design Limited | Professional & scientific | 1997 |
| Unitech Engineering Services Limited | Professional & scientific | 1990 |
| Unitech Fabrications Limited | Manufacturing | 2025 |
| Unitech Property Services (Newbury) Limited | Real estate | 2021 |
| Unitech Residential Services Limited | Real estate | 2024 |
| United Konsultants Limited | Information & communication | 2013 |
| Unity Automotive Holdings Ltd | Financial services | 2025 |
| Unknown Hair Space Limited | Other services | 2021 |
| Unorthodox Films Ltd | Information & communication | 2019 |
| UP in Smoke BBQ Limited | Hospitality | 2018 |
| Updown Farmhouse (Holdings) Limited | Financial services | 2023 |
| Updown Farmhouse Ltd | Hospitality | 2020 |
| Upton Grange Investments Ltd | Financial services | 2020 |
| Urban Grill Newbury Limited | Hospitality | 2025 |
| Urban Storage & Living Ltd | Financial services | 2020 |
| Urbanshare Opportunity Fund Limited Partnership | | 2009 |
| Usefulalus Limited | Construction | 2021 |
| USL a Ltd | Real estate | 2020 |
| Uventop Limited | Real estate | 2012 |
| UVN Consultants Ltd | Information & communication | 2025 |
| UX Skills Ltd | Information & communication | 2014 |
| Vadned & CVM Ltd | Construction | 2020 |
| Validity Limited | Information & communication | 2005 |
| Valley Cars Limited | Transport & logistics | 2014 |
| Valonon Ltd | Professional & scientific | 2015 |
| Value Accountants Ltd | Professional & scientific | 2019 |
| Value Bridge Advisory Ltd | Professional & scientific | 2015 |
| VAM Thomas Talent Ltd | Information & communication | 2024 |
| Vanessco Limited | Water & waste | 2015 |
| Vanilla Rain Ltd | Professional & scientific | 2022 |
| Vanilla Sky Technology Limited | Information & communication | 2014 |
| Vanson Bourne Limited | Professional & scientific | 1999 |
| Vantage Data Centers UK Limited | Information & communication | 2007 |
| Varad Agritech UK Ltd | Wholesale & retail | 2023 |
| Variablex Software Services Limited | Information & communication | 2024 |
| Vash Production UK Limited | Information & communication | 2018 |
| Vassago Property Ltd | Real estate | 2016 |
| Vaughan Plumbing Limited | Construction | 2010 |
| Vawal Ltd | Manufacturing | 2021 |
| VCH Commissioning Limited | Construction | 2018 |
| Vcloud Solutions Limited | Information & communication | 2012 |
| Vcmr Ltd | Professional & scientific | 2021 |
| Vector Operations Advisory Ltd | Professional & scientific | 2026 |