| Tilegate Road Management Company Limited | Households | 2008 |
| Tina J Photography Limited | Professional & scientific | 2020 |
| Tj's (London) Limited | Wholesale & retail | 2023 |
| TM Touring Ltd | Professional & scientific | 2025 |
| TNG Services Group Ltd. | Construction | 2013 |
| Toast Beauty Limited | Other services | 2025 |
| Toast Tanning Essex Limited | Other services | 2023 |
| Together Consultants Ltd | Construction | 2018 |
| Tokeley Ltd | Water & waste | 2020 |
| Tolleshunt Tree Care Limited | Administrative & support | 2025 |
| Tommy Tuck Limited | Wholesale & retail | 2023 |
| Toot Hill Golf Club Limited | Arts & recreation | 1991 |
| Toothill Development Limited | Construction | 2021 |
| Top Access Scaffolding Limited | Construction | 2014 |
| Top London Contractors Ltd | Construction | 2021 |
| Total Roofing & Guttering Ltd | Construction | 2025 |
| Totoka Ltd | Wholesale & retail | 2021 |
| Tough Love Equestrian Ltd | Manufacturing | 2025 |
| Tower Group Investments Ltd | Other services | 2016 |
| Tower Management Ltd | Professional & scientific | 2024 |
| TPE Developments Limited | Construction | 2011 |
| Transform Accounting Ltd | Professional & scientific | 2012 |
| Treasure Keepers Ltd | Health & social care | 2011 |
| Trelease-Gray Limited | Extraterritorial | 2006 |
| Treopoint Limited | Transport & logistics | 2025 |
| Trident Point Limited | Professional & scientific | 2022 |
| Trilogy Holdings Ltd | Real estate | 2003 |
| Trilogy Property Limited | Real estate | 1999 |
| Trinity House RTM Company Limited | Real estate | 2013 |
| Trojan Ltd | Transport & logistics | 2021 |
| TS Renewables Co Ltd | Construction | 2023 |
| Tspi Ltd | Real estate | 2015 |
| Turkwise Limited | Hospitality | 2016 |
| Turner Properties Management Ltd | Real estate | 2017 |
| Turners Properties Ltd | Real estate | 2018 |
| TVP Hire Ltd | Administrative & support | 2025 |
| TW1 Boxing Gym Limited | Arts & recreation | 2020 |
| Tweek Cosmetics Limited | Other services | 2015 |
| Twig Dogs Ltd | Other services | 2023 |
| Tyler Developments Limited | Construction | 2022 |
| U 70 Limited | Manufacturing | 2014 |
| Ubervisor Limited | Information & communication | 2026 |
| UBS Hoists and Access Limited | Construction | 2005 |
| Uddin Family Commercial Ltd | Real estate | 2019 |
| UK Medical Medico Limited | Information & communication | 2013 |
| Ukpatches Ltd | Manufacturing | 2018 |
| Unified Synergy Limited | Other services | 2018 |
| United Drains Ltd | Water & waste | 2017 |
| Upgrade Performance Group Limited | Professional & scientific | 2026 |
| V&A Contracts Ltd | Construction | 2022 |
| V. Page Building Services Ltd. | Construction | 2003 |
| VAL Robinson Childcare Services Limited | Health & social care | 2016 |
| Vape Venda Limited | Wholesale & retail | 2026 |
| Ventexpress Limited | Construction | 1998 |
| Ventilation Express Limited | Professional & scientific | 1998 |
| Venture Services London Limited | Professional & scientific | 2010 |
| Verbs Plus Ltd | Professional & scientific | 2021 |
| Vitacheck Ltd | Professional & scientific | 2020 |
| VKW Electrical Ltd | Construction | 2013 |
| Voice LAB Network Ltd | Information & communication | 2024 |
| Vojan Dining Ltd | Hospitality | 2026 |
| VR Lounge Ltd | Hospitality | 2026 |
| VSN Associates Limited | Administrative & support | 2019 |
| VTD 68 Ltd | Other services | 2023 |
| W.Chest Holdings Ltd | Financial services | 2023 |
| Wake and Bakery Ltd | Wholesale & retail | 2018 |
| Wantz 4 Change Ltd | Real estate | 2005 |
| Ward & Grace Partners Limited | Construction | 2026 |
| Warwickshire Hotel Investment Limited | Construction | 2024 |
| Watson Pearce Properties Limited | Real estate | 2017 |
| Waypoint Tech Limited | Information & communication | 2016 |
| Webuyyourclassiccars Ltd | Wholesale & retail | 2023 |
| Wellmaze Property Management Limited | Real estate | 2006 |
| Weru Ltd | Wholesale & retail | 2023 |
| West One Group Limited | Construction | 2009 |
| Western Front Services Limited | Administrative & support | 2021 |
| Wexford Advisory Limited | Professional & scientific | 2022 |
| Weybrook Investments Limited | Construction | 1953 |
| Whiskey 8 Limited | Professional & scientific | 2011 |
| Whistle's Wardrobe Ltd | Wholesale & retail | 2025 |
| White Partners Limited | Real estate | 2026 |
| Whitefields Decor Ltd | Wholesale & retail | 2021 |
| Whiteknights Holding Company Limited | Financial services | 2025 |
| William Allison (Leys) Limited | Financial services | 2025 |
| William Allison Holding Limited | Financial services | 2025 |
| Williams Electrical Services Limited | Construction | 1994 |
| Winners Mentality Ltd | Wholesale & retail | 2020 |
| WOK About Limited | Hospitality | 2012 |
| Woodford Computers Ltd | Information & communication | 1999 |
| Woodford Golf Club Limited | Arts & recreation | 2022 |
| Woodford Golf Club Trading Company Limited | Arts & recreation | 2020 |
| Woodfords Construction Limited | Construction | 2024 |
| Woodruff Works Limited | Health & social care | 2018 |
| Woolmongers Property Limited | Real estate | 2020 |
| Workhive Limited | Real estate | 2016 |
| World Master Chefs Limited | Hospitality | 2000 |
| World Wide Futures Limited | Real estate | 1998 |
| Wrenn Electrical Services Ltd | Construction | 2021 |
| Wrightway Construction and Maintenance Ltd | Construction | 2019 |
| Xcel Motorsport UK Ltd | Arts & recreation | 2023 |