| Tricord Consulting Group Limited | Information & communication | 2024 |
| Tricord Properties Limited | Real estate | 2009 |
| Trident Estates & Lettings Limited | Real estate | 2026 |
| Trinitycap Ltd | Financial services | 2025 |
| Triomphe Consulting Limited | Professional & scientific | 2025 |
| Triple Shot Coffee Ltd | Hospitality | 2024 |
| Tropical Beauty Salon Ltd | Other services | 2026 |
| Truck Parts Solutions Ltd | Wholesale & retail | 2023 |
| Tryfina Ltd | Health & social care | 2013 |
| TS Property & Maintenance Ltd | Real estate | 2020 |
| TS Roofing Building Services Ltd | Construction | 2025 |
| Tsbl Limited | Wholesale & retail | 2022 |
| TSM LDN Ltd | Administrative & support | 2023 |
| Tuckfield & Co. Ltd | Real estate | 2024 |
| Tuhura Ltd | Education | 2023 |
| Tuitus Media Limited | Professional & scientific | 2003 |
| Tuna Bookkeeping and Financial Consultancy Limited | Professional & scientific | 2021 |
| Tungsten Consulting Group Limited | Professional & scientific | 2015 |
| Turco Medical Ltd | Wholesale & retail | 2022 |
| Turtle Mortgages Ltd | Financial services | 2024 |
| Tusken Limited | Administrative & support | 2009 |
| TW Nikel Limited | Transport & logistics | 2014 |
| Twenty Two Solutions Ltd | Administrative & support | 2018 |
| Two 9 Property Group Ltd | Construction | 2024 |
| Tyson's RAW Ltd. | Manufacturing | 2020 |
| UA Tech London Ltd | Information & communication | 2026 |
| Ucammi Limited | Wholesale & retail | 2024 |
| Ucan International Trading and Consultancy Ltd | Wholesale & retail | 2019 |
| Uchi Harpenden Limited | Professional & scientific | 2011 |
| Ucinity Ltd | Professional & scientific | 2012 |
| Udalowo Ltd | Real estate | 2026 |
| Ugur Baran Hairdresser Ltd | Other services | 2020 |
| UK Asbestos Services Limited | Professional & scientific | 2006 |
| UK Corporate Advisory (Aust) Ltd | Professional & scientific | 2015 |
| UK Corporate Advisory Ltd | Professional & scientific | 2013 |
| UK Gili Ltd | Manufacturing | 2014 |
| UK Recycling Services Limited | Wholesale & retail | 2025 |
| UK Safety Services Ltd | Other services | 2022 |
| Uldedaj.Bxng Limited | Arts & recreation | 2025 |
| Ullmer Group Limited | Professional & scientific | 2017 |
| Ultrox Holdings Limited | Financial services | 2022 |
| Ultrox Limited | Professional & scientific | 2021 |
| Undivided Ltd | Arts & recreation | 2013 |
| Unifai Holdings Limited | Information & communication | 2016 |
| Unifydata LLP | | 2019 |
| Unique IT Support Limited | Information & communication | 2013 |
| Univere Investment Solutions Limited | Administrative & support | 2025 |
| Unknown Collections 20 Ltd | Wholesale & retail | 2023 |
| Unseen Media Group Ltd | Professional & scientific | 2022 |
| Unsupervised Productions Ltd | Information & communication | 2026 |
| UP in the Air Ltd | Financial services | 2022 |
| Upmatch Ltd | Information & communication | 2021 |
| Upper Gade Flyfishers and Conservation Association Limited | Arts & recreation | 2005 |
| Urban Pearl Interiors Ltd | Construction | 2019 |
| Uskuri Theobald Architects Ltd | Professional & scientific | 2019 |
| Utest UK Limited | Manufacturing | 2020 |
| Utility Computing Limited | Information & communication | 2004 |
| UVG Limited | Administrative & support | 2025 |
| UW Trade Services Ltd | Other services | 2018 |
| V&V Model Limited | Professional & scientific | 2013 |
| Vaert AI Limited | Information & communication | 2025 |
| Valency Limited | Financial services | 1994 |
| Van Rentals 247 Limited | Administrative & support | 2026 |
| Vanilla Collective Ltd | Arts & recreation | 2011 |
| Vanlife and Overlander Celebration 23 Ltd | Wholesale & retail | 2022 |
| Vanlife Celebration Ltd | Wholesale & retail | 2022 |
| Vantage Land & Property Ltd | Real estate | 2025 |
| Variety Productions Limited | Information & communication | 2025 |
| Vario London Ltd | Wholesale & retail | 2023 |
| VBM Technology and Business Solutions Limited | Information & communication | 2023 |
| Vector Fit Ltd | Arts & recreation | 2017 |
| Vector Strategic Solutions Limited | Professional & scientific | 2015 |
| Vega Analysis Ltd | Professional & scientific | 2023 |
| Verde Masoni Ltd | Wholesale & retail | 2023 |
| Verge Group Limited | Construction | 2018 |
| Vertical Line Theatre Ltd | Arts & recreation | 2013 |
| Vertu Properties Ltd | Real estate | 2023 |
| Verulam Electrical Ltd | Construction | 2026 |
| Verve Books Ltd | Information & communication | 2015 |
| VIA Tourism Limited | Wholesale & retail | 2021 |
| Vibe Lighting Ltd | Wholesale & retail | 2026 |
| Victor Alves-Nores Ltd | Professional & scientific | 2026 |
| Videoo Limited | Information & communication | 2024 |
| Vidro Ltd | Professional & scientific | 2020 |
| Viewnote Freehold Limited | Administrative & support | 2003 |
| Viewpremium Property Management Limited | Households | 1995 |
| Vikaas Talent Limited | Professional & scientific | 2016 |
| Vila Real Renov Ltd | Wholesale & retail | 2025 |
| Village Estates Laleham Limited | Real estate | 2013 |
| Village Lettings Limited | Real estate | 2019 |
| Village Mews Property Limited | Households | 1995 |
| Village Vehicles Limited | Wholesale & retail | 1996 |
| Vincere Consultancy Services Limited | Professional & scientific | 2025 |
| Virgo HR Limited | Administrative & support | 2024 |
| Virtus GBR Limited | Wholesale & retail | 2025 |
| Visa Flow AI Ltd | Information & communication | 2026 |
| Visage DE LUX Ltd | Wholesale & retail | 2025 |
| Visionary Ecom Ltd | Wholesale & retail | 2020 |
| Visionseek Limited | Real estate | 1990 |
| Visual Identity Management Limited | Professional & scientific | 2003 |