| Tuscawilla Care Group Ltd | Health & social care | 2019 |
| Tussell Traders Ltd | Wholesale & retail | 2025 |
| Tuva Collection Ltd | Manufacturing | 2024 |
| TW Cleaning Services Ltd | Administrative & support | 2024 |
| TW Dean Enterprises LLP | | 2007 |
| TW Dean Group Limited | Financial services | 2007 |
| TW Solicitors Ltd | Professional & scientific | 2016 |
| Twc&L Ltd | Construction | 2024 |
| TWD Training Limited | Education | 2022 |
| TWD Ward Holdings Limited | Financial services | 2025 |
| Twelve Behind UK Ltd | Administrative & support | 2019 |
| Twelve Roses Limited | Other services | 2019 |
| TWELVE59 Ltd | Professional & scientific | 2011 |
| Twenty Four Digital Media Ltd | Professional & scientific | 2016 |
| Twenty One United Ltd | Administrative & support | 2024 |
| TWENTY23 Marketing Ltd | Professional & scientific | 2015 |
| TWENTY4SEVEN Homes Ltd | Households | 2021 |
| TWENTY4SEVEN Site Services Ltd | Construction | 2020 |
| TWENTY4SEVEN Trade Waste Ltd | Water & waste | 2025 |
| TWENTY4SEVEN Waste Management Limited | Water & waste | 2015 |
| Twentynine TM Limited | Construction | 2024 |
| Twin Capital Holdings Ltd | Financial services | 2025 |
| Twin Palace Ltd | Hospitality | 2009 |
| Twin Peaks Investment Ltd | Real estate | 2023 |
| Twin Ventures International Cromwell Road Limited | Wholesale & retail | 2025 |
| Twin Ventures International Limited | Manufacturing | 1995 |
| Twin Ventures International Loughborough Road Limited | Wholesale & retail | 2025 |
| Twin Ventures International Peace Limited | Wholesale & retail | 2025 |
| Twin Ventures International Ramsey House Limited | Wholesale & retail | 2025 |
| TWM Haulage Ltd | Transport & logistics | 2016 |
| Two Blues Limited | Construction | 2024 |
| Two Fifty Short Limited | Administrative & support | 2022 |
| Two Techs (Dartford) Limited | Wholesale & retail | 2010 |
| TWS Property Management Limited | Households | 2019 |
| Typhon Studio Ltd | Information & communication | 2021 |
| Tyrrell-Lewis Associates Limited | Information & communication | 1995 |
| U.C.O Properties Ltd | Real estate | 2022 |
| U4S Solutions Ltd | Administrative & support | 2023 |
| Uappacademy Ltd | Education | 2024 |
| UAUDIT24 Ltd | Information & communication | 2025 |
| UBS Financial Management Ltd | Other services | 2025 |
| UFC Gym Fit OUT UK Limited | Construction | 2025 |
| UFC Orpington Ltd | Arts & recreation | 2025 |
| UGO Paulon Ltd | Manufacturing | 2020 |
| UIC Events LP | | 2009 |
| UK ADI Services Limited | Construction | 2015 |
| UK Boiler Installations Limited | Construction | 2019 |
| UK Building Interior Ltd | Construction | 2019 |
| UK Business Affairs Limited | Professional & scientific | 2016 |
| UK Centres and Trainers Organisation CIC | Other services | 2025 |
| UK Construction Supplies Ltd | Construction | 2024 |
| UK Dalian Association Ltd | Other services | 2020 |
| UK Dancehall Entertainment Ltd | Information & communication | 2024 |
| UK Deep Clean Limited | Administrative & support | 2018 |
| UK Facilities Solutions Ltd | Real estate | 2013 |
| UK Fostering (MNW) Limited | Health & social care | 2016 |
| UK Fostering (NE) Limited | Health & social care | 2016 |
| UK Fostering Limited | Health & social care | 2012 |
| UK Goshen Hope & Empowerment Relief Ltd | Other services | 2024 |
| UK Hindu Cultural Centre (Ukhcc) Ltd | Education | 2019 |
| UK Leadership Awards for Excellence Ltd | Professional & scientific | 2024 |
| UK Lift Inspection Services Ltd | Professional & scientific | 2025 |
| UK Paints Ltd | Wholesale & retail | 2024 |
| UK Pet and Aquatics Limited | Wholesale & retail | 2020 |
| UK Quincyzhaochuan International Trading Co., Limited | Wholesale & retail | 2021 |
| UK Rapid Movements Ltd | Households | 2021 |
| UK Tiantian Education Ltd | Administrative & support | 2018 |
| UK Traffic Safety Ltd | Construction | 2016 |
| Ukac Wholesale Limited | Wholesale & retail | 2024 |
| Ukfm Warehousing and Distribution Limited | Transport & logistics | 2014 |
| UL15 Trading Ltd | Other services | 2017 |
| Ultimate Business Limited | Extraterritorial | 2015 |
| Ultimate Developers Limited | Real estate | 2020 |
| Ultimate Engineers Limited | Construction | 2021 |
| Ultimate Hygiene Care Limited | Health & social care | 2015 |
| Ultimate Perfection Ltd | Hospitality | 2024 |
| Ultimate Spotless Ltd | Administrative & support | 2016 |
| Ultimate Zanata Limited | Construction | 2013 |
| Ultra Contracting Services Ltd | Construction | 2024 |
| Ultra Dove Properties Limited | Real estate | 2020 |
| Ultrasound Partners Limited | Health & social care | 2016 |
| Ultronix Ltd | Wholesale & retail | 2026 |
| Ulustrans UK Ltd | Transport & logistics | 2007 |
| UN Toque Agency Ltd | Professional & scientific | 2019 |
| Unalome Consultancy Ltd | Administrative & support | 2023 |
| Uncle Beef Ltd | Manufacturing | 2018 |
| Uncle Beef Street Food Ltd | Hospitality | 2021 |
| Unclouded Solar Ltd | Construction | 2017 |
| Undirected FUN Limited | Professional & scientific | 2025 |
| Unghar Investments Limited | Administrative & support | 2013 |
| UNI Health Distribution Ltd | Manufacturing | 2015 |
| Unic Associates Limited | Manufacturing | 2012 |
| Unic Group Ltd | Construction | 2020 |
| Uniclamp Ltd | Manufacturing | 2014 |
| Unico Dartford Ltd | Hospitality | 2024 |
| Unicorn 73 Ltd | Extraterritorial | 2011 |
| Unicorn Property Limited | Construction | 1998 |
| Unicorn Uniforms Ltd | Wholesale & retail | 2013 |
| Unified Security Ltd | Information & communication | 2009 |
| Unigrad Ltd | Education | 2024 |