| Thirstfix Dispense Services Limited | Professional & scientific | 2016 |
| Thirty SIX Eighty SIX Ltd | Hospitality | 2026 |
| This Art of Mine Ltd | Arts & recreation | 2010 |
| Thom Kirby Hair Limited | Other services | 2015 |
| Thomas & Anca Supplies Limited | Administrative & support | 1998 |
| Thomas Accounts Limited | Professional & scientific | 2019 |
| Thomas Cookie Company Limited | Manufacturing | 2014 |
| Thompson Consulting Services Limited | Other services | 2001 |
| Thompson Electrical Services Limited | Construction | 1995 |
| Thompsons Chemist Limited | Wholesale & retail | 2012 |
| Thorne Logistics Ltd | Transport & logistics | 2025 |
| Thorne Property Management Limited | Real estate | 2021 |
| Thorne Studio Limited | Arts & recreation | 2025 |
| Thort Group Limited | Extraterritorial | 2020 |
| Thost Ltd | Wholesale & retail | 2021 |
| Three Arches Care Ltd | Health & social care | 2012 |
| Three Generations Roofing Ltd | Construction | 2021 |
| Three Little PEA Homes Limited | Hospitality | 2024 |
| Three Mills 3BEANS Limited | Arts & recreation | 2025 |
| Three Mills Fitness Limited | Arts & recreation | 2019 |
| Three Peaks Challenge Limited | Administrative & support | 2009 |
| Three Sixty Film Services Ltd | Administrative & support | 2022 |
| Three Towns Office Equipment Limited | Wholesale & retail | 1971 |
| Threeay Property Ltd | Real estate | 2026 |
| Threesixty Mind Ltd | Administrative & support | 2021 |
| Thrifty by Design Ltd | Professional & scientific | 2023 |
| Thriveyy Ltd | Information & communication | 2026 |
| Thrombosis UK | Other services | 2002 |
| Throughput Solutions Limited | Professional & scientific | 2026 |
| Thsfx Limited | Manufacturing | 2024 |
| Thumbed Books Ltd. | Professional & scientific | 2004 |
| Thunder Connection Ltd | Transport & logistics | 2020 |
| THY Barber Ltd | Other services | 2017 |
| THY Barber Retail Ltd | Wholesale & retail | 2017 |
| TI22 Consulting Ltd | Administrative & support | 2017 |
| Tide Tribe Ltd | Wholesale & retail | 2023 |
| Tidy International (UK) Limited | Information & communication | 2009 |
| Tidy Touch Housekeeping Maidstone Ltd | Administrative & support | 2024 |
| Tiffany 89 Limited | Transport & logistics | 2020 |
| Tiffany Heights Management Limited | Households | 1999 |
| Tiger Collar Estates Limited | Construction | 2022 |
| Tiger Post Limited | Professional & scientific | 2017 |
| Tiger Professional Services Ltd | Financial services | 2021 |
| Tigernet Ltd | Information & communication | 2024 |
| Tiginairgid Ltd | Real estate | 2026 |
| Tile Giant Ltd | Extraterritorial | 2026 |
| Till Holdings Limited | Financial services | 2019 |
| Tilly Sweet Treats Limited | Other services | 2025 |
| Tilney Morris Homes Ltd | Real estate | 2018 |
| Tilt and PAN Limited | Information & communication | 2023 |
| Tilyard Autos Limited | Wholesale & retail | 2008 |
| Tilyard Holdings Limited | Financial services | 2023 |
| TIM Doust & Associates Limited | Professional & scientific | 2018 |
| TIM Holloway Funeral Support Ltd | Other services | 2008 |
| TIM Wood Healthcare Ltd | Health & social care | 2012 |
| Timbert Ltd | Wholesale & retail | 2019 |
| Time for Children Limited | Health & social care | 1999 |
| Times Tuition Ltd | Education | 2023 |
| Timon Detection and Integrity Limited | Construction | 2015 |
| Timon Fire Protection Limited | Construction | 2010 |
| Timon Property Investment Limited | Real estate | 2017 |
| Tina MAK Ltd | Manufacturing | 2023 |
| Tinder Corporation Civils Ltd | Construction | 2025 |
| Tinder Corporation Ltd | Information & communication | 2009 |
| Tindlegreens Limited | Real estate | 1978 |
| Tinka Investments Ltd | Real estate | 2019 |
| Tinker Trays Ltd | Wholesale & retail | 2025 |
| Tintin Consultants Ltd | Administrative & support | 2023 |
| Tinton Management Ltd | Professional & scientific | 2014 |
| Tinton Property Limited | Real estate | 2025 |
| TIP Top Beauty Ltd | Other services | 2018 |
| Tipple Media (Dooh) Limited | Professional & scientific | 2026 |
| Tipsy Tweed Ltd | Administrative & support | 2020 |
| Tirdis Investments Ltd | Real estate | 2016 |
| Tirebu Ltd | Information & communication | 2025 |
| Tiska Properties Ltd | Real estate | 2024 |
| Titan Auto Services Ltd | Wholesale & retail | 2025 |
| Titanstone Capital Partners Limited | Construction | 2025 |
| Titch Ltd | Professional & scientific | 2026 |
| Titlefirst Property Management Limited | Households | 1994 |
| Tiwa Site Solutions Ltd | Administrative & support | 2024 |
| TJM Logistics Limited | Transport & logistics | 2021 |
| TK Lowe Properties Ltd | Real estate | 2023 |
| TK Ventilation Ltd | Energy | 2021 |
| TK- Mind Consultants Ltd | Administrative & support | 2018 |
| TKJ Marketing Ltd | Wholesale & retail | 2024 |
| TM Fire and Security Limited | Energy | 2018 |
| TMA Kickboxing Academy Ltd | Arts & recreation | 2013 |
| TMB Painters and Decorators and Repair Specialists Ltd | Construction | 2017 |
| TMC Drilling Ltd | Construction | 2024 |
| TMC Groundworks & Landscaping Ltd | Construction | 2024 |
| TMC Security Services Ltd | Administrative & support | 2022 |
| TMC Social Care Ltd | Health & social care | 2025 |
| TME Digital Ltd | Information & communication | 2005 |
| TMH 70 Ltd | Construction | 2022 |
| TMH Client Account Ltd | Real estate | 2019 |
| TMH10 Development Ltd | Construction | 2019 |
| TMH15 Development Ltd | Real estate | 2020 |
| TMH40 Development Ltd | Real estate | 2020 |
| TML (South East) Ltd | Construction | 2025 |