| Taylors Heating & Plumbing Services Ltd | Construction | 2023 |
| Taymo Air Conditioning Limited | Energy | 2026 |
| Tazara Ltd | Professional & scientific | 2023 |
| Tazmania Drive Ltd | Transport & logistics | 2016 |
| TBF Pubs Ltd | Financial services | 2023 |
| TBP2 Limited | Information & communication | 2009 |
| TCD Group Limited | Construction | 2015 |
| TCT Group Limited | Professional & scientific | 2016 |
| TDC Research Ltd | Professional & scientific | 2014 |
| Tdto Ltd | Information & communication | 2018 |
| TE Energy Consulting Ltd | Professional & scientific | 2025 |
| Tea Rituals Ltd | Wholesale & retail | 2025 |
| Teachtalklearn Limited | Education | 2017 |
| Teacoffeeco Ltd | Wholesale & retail | 2019 |
| Team Conflict Ltd | Arts & recreation | 2025 |
| Team Medic (London) Limited | Health & social care | 2013 |
| Team Medic Academy Ltd | Education | 2025 |
| Team Medic Limited | Real estate | 2018 |
| Team Medical Services Ltd | Professional & scientific | 2023 |
| Team Spiral Ltd. | | 1994 |
| Team Swim School Ltd | Arts & recreation | 2015 |
| Teamviewer UK Limited | Information & communication | 2014 |
| Teamwide Accounting Limited | Professional & scientific | 2007 |
| Tech Cars Ltd | Transport & logistics | 2023 |
| Tech Lovers Ltd | Wholesale & retail | 2018 |
| Techappia Ltd | Information & communication | 2015 |
| Techbrix Ltd | Real estate | 2022 |
| TECHIT360 Limited | Information & communication | 2024 |
| Techlyts Consulting Limited | Information & communication | 2017 |
| Technical Spares Limited | Information & communication | 2001 |
| Technologise Ltd | Information & communication | 2020 |
| Technology Investments Ltd | Professional & scientific | 2013 |
| Techreza Ltd | Information & communication | 2011 |
| Techrover Ltd | Wholesale & retail | 2019 |
| Teddington & Richmond Roofing Limited | Construction | 2018 |
| Tejase Yoga Training Ltd | Education | 2020 |
| Telion Architectural Designs LLP | | 2010 |
| Tellings Golden Miller Ltd | Transport & logistics | 2015 |
| Temple Tile and Stone Limited | Extraterritorial | 2017 |
| Templeco 670 Limited | Administrative & support | 2011 |
| TEN10 Films Limited | Information & communication | 2011 |
| TEN20 Media Ltd | Administrative & support | 2021 |
| Tenens AI Ltd | Information & communication | 2026 |
| Tenmegawattun Limited | Wholesale & retail | 2022 |
| Tenuto 67 Limited | Other services | 2020 |
| TEQ Solutions Ltd | Construction | 2024 |
| Tern House Limited | Hospitality | 2010 |
| Terra Zuri Ltd | Administrative & support | 2026 |
| TERRA360 Ltd | Information & communication | 2024 |
| Testing Frameworks Ltd | Information & communication | 2016 |
| Teszler Ltd | Information & communication | 2025 |
| Teviot Bernard Investments Ltd | Professional & scientific | 2022 |
| TF Analysis Limited | Professional & scientific | 2016 |
| TFM Fencing Ltd | Construction | 2023 |
| TFM Group Ltd | Construction | 2025 |
| TG GRG Ltd | Real estate | 2026 |
| Tgrfoc Ltd | Real estate | 2018 |
| Thakady Services Ltd | Construction | 2014 |
| Thaleron Limited | Professional & scientific | 2022 |
| Thames & Threads Limited | Wholesale & retail | 2024 |
| Thames Carpentry Ltd | Construction | 2024 |
| Thames Home London Ltd | Real estate | 2017 |
| Thameside Special Projects Ltd | Construction | 2013 |
| That One There Ltd | Professional & scientific | 2023 |
| THB (Surrey) Limited | Professional & scientific | 2009 |
| THB LLP | | 2007 |
| THE 12 Partnership Ltd | Financial services | 2022 |
| THE Academy of Hair Limited | Other services | 2010 |
| THE Accident Claim & Hire Solution Ltd | Financial services | 2019 |
| THE AI Corporation Limited | Information & communication | 1998 |
| THE Alchemist Arts Collective Limited | Arts & recreation | 2013 |
| THE Ambar Room Ltd | Education | 2025 |
| THE Ambassador Entertainment Group Limited | Arts & recreation | 2009 |
| THE Ambassador Theatre Group (Venues) Limited | Arts & recreation | 1979 |
| THE Ambassador Theatre Group Limited | Arts & recreation | 2015 |
| THE Ambassador Theatre Group Overseas Holdings Limited | Arts & recreation | 2013 |
| THE American Trading Company (Holdings) Limited | Real estate | 1927 |
| THE American Trading Company Limited | Extraterritorial | 1991 |
| THE Ants Nest Limited | Professional & scientific | 2023 |
| THE Armstrong Close Management Company Limited | Households | 1988 |
| THE Art Escape Ltd | Arts & recreation | 2026 |
| THE Artisan Hub Ltd | Wholesale & retail | 2023 |
| THE Athena Foundation Limited | Other services | 2016 |
| THE Athwal's 71 Ltd | Wholesale & retail | 2026 |
| THE Audio Lounge Ltd | Information & communication | 2025 |
| THE Avocado Shop Limited | Wholesale & retail | 2020 |
| THE Barbeque Shop Limited | Administrative & support | 2011 |
| THE BAT- MAN Group Ltd | Other services | 2016 |
| THE Beech Consulting Services Limited | Professional & scientific | 2025 |
| THE Beeches (Knaphill) Management Co. Limited | Households | 2006 |
| THE Bentley Collection Limited | Wholesale & retail | 2000 |
| THE Bespoke Fittings Company Ltd | Manufacturing | 2015 |
| THE Big Drink Company Ltd | Wholesale & retail | 2020 |
| THE BOC Foundation | Professional & scientific | 1990 |
| THE BOC Group Limited | Professional & scientific | 1886 |
| THE Breath Space Ltd | Health & social care | 2020 |
| THE British Oxygen Company Limited | Extraterritorial | 1957 |
| THE Brooks Partnership Limited | Professional & scientific | 1996 |
| THE Buddies Ltd | Information & communication | 2022 |
| THE Burch Group Limited | Administrative & support | 2025 |