| TDCLEANING77 Ltd | Other services | 2012 |
| TE Ajudo UK Immigration Advice Ltd | Professional & scientific | 2026 |
| Techprof Ltd | Information & communication | 2011 |
| Techttonic Limited | Professional & scientific | 2024 |
| Tecxodus Ltd | Information & communication | 2026 |
| Telco Parts Ltd | Wholesale & retail | 2025 |
| Telemar (UK) Limited | Transport & logistics | 1999 |
| Telson Roofwise Limited | Construction | 2019 |
| Temis Luxury (UK) Ltd | Transport & logistics | 2019 |
| Templehill Estates Ltd | Real estate | 2003 |
| Tempura Communications Ltd | Information & communication | 1998 |
| Tempura Connect Ltd | Information & communication | 2014 |
| Tempura Technology Ltd | Information & communication | 2014 |
| Temvo Ltd | Information & communication | 2025 |
| Terrapins (Surbiton) Residents Association Limited | Households | 1970 |
| Th@T Rigging Company Limited | Information & communication | 2019 |
| Thames Tour Ltd | Administrative & support | 2011 |
| Thamo Estates Limited | Real estate | 2025 |
| Thanya Ltd | Hospitality | 2022 |
| That Amazing Gift Company Ltd | Wholesale & retail | 2023 |
| THE 35 House Limited | Households | 1999 |
| THE Barn KT9 Ltd | Hospitality | 2021 |
| THE Blue Brown Green Company Ltd | Wholesale & retail | 2020 |
| THE Business Solutions Bureau Ltd | Professional & scientific | 2025 |
| THE Dreams Loft Ltd | Construction | 2021 |
| THE Driftbridge RTM Company Limited | Extraterritorial | 2026 |
| THE Fabrika Group Ltd | Professional & scientific | 2023 |
| THE Firs Residents Company Limited | Households | 2001 |
| THE Garage Roof Company Ltd | Real estate | 2020 |
| THE Glow K Ltd | Wholesale & retail | 2021 |
| THE Golden Dome Limited | Wholesale & retail | 2022 |
| THE Granary Limited | Real estate | 2001 |
| THE Green App Limited | Wholesale & retail | 2025 |
| THE Grey Space Coaching Ltd | Other services | 2017 |
| THE Hosting Edit Ltd | Households | 2026 |
| THE Limes RTM Company Limited | Hospitality | 2009 |
| THE Little Borough Ltd | Hospitality | 2025 |
| THE Little Coffee Club Ltd | Hospitality | 2022 |
| THE Manor Gardens RTM Company Ltd | Households | 2011 |
| THE Minazi Impact Ltd | Professional & scientific | 2022 |
| THE MORE68 Ltd | Hospitality | 2022 |
| THE Old Cellar Ltd | Wholesale & retail | 2011 |
| THE Old Coach House RTM Company Ltd | Households | 2014 |
| THE Packaging Boxes Limited | Administrative & support | 2024 |
| THE Sitare Limited | Other services | 2018 |
| THE Social Gathering Company Ltd | Arts & recreation | 2025 |
| THE Stop Riverside Limited | Hospitality | 2024 |
| THE Taylormade Financial Management Partnership LLP | | 2007 |
| THE Teddington Water Company Limited | Water & waste | 2007 |
| THE Throne of Grace Ministries Limited | Education | 2018 |
| THE Underdogue Ltd | Wholesale & retail | 2016 |
| THE Unlucky Rovers Ltd | Professional & scientific | 2024 |
| THE Welldons Partnership Limited | Professional & scientific | 2025 |
| THE White House Limited | Professional & scientific | 1980 |
| Thegreenage Ltd | Information & communication | 2011 |
| Theumi Ltd | Hospitality | 2016 |
| Thili Rose James Limited | Professional & scientific | 2023 |
| Think Logistics & Solutions Ltd | Construction | 2010 |
| Three Angels INT Limited | Wholesale & retail | 2013 |
| Thripple-Thrift Limited | Wholesale & retail | 1989 |
| Tien POH Health Limited | Wholesale & retail | 2012 |
| TIM Hendy Pianos Ltd | Professional & scientific | 2008 |
| Timber Window and Door Group Ltd | Construction | 2019 |
| Timoshonco UK Limited | Construction | 2019 |
| Titan AJ Construction Limited | Construction | 2023 |
| TM Roofing Services Ltd | Construction | 2025 |
| TO Everywhere Ltd | Manufacturing | 2025 |
| Todi and Boys Limited | Construction | 2013 |
| Todorov EL Ltd | Construction | 2015 |
| Tolini Ltd | Construction | 2017 |
| TOM Grondi Ltd | Manufacturing | 2017 |
| TOM Refurbishments Ltd | Construction | 2011 |
| Tomkins Project Consultants Ltd | Professional & scientific | 2016 |
| Tony Schaffer Agencies Limited | Other services | 2017 |
| Tonyareiwo Limited | Health & social care | 2023 |
| Topacio Holding Limited | Financial services | 2024 |
| Topaz Limited | Wholesale & retail | 1996 |
| Topnote Ltd | Information & communication | 2026 |
| Topwest Limited | Wholesale & retail | 2004 |
| Toraman Limited | Hospitality | 2018 |
| Toraman Properties Limited | Real estate | 2024 |
| Totaconstruction Ltd | Construction | 2026 |
| Total Plumbing Heating and GAS Ltd. | Construction | 2018 |
| Totalbright Ltd | Administrative & support | 2026 |
| Tourplus Ltd | Administrative & support | 2019 |
| Tprofestate Ltd | Real estate | 2022 |
| Traceypitches Ltd | Other services | 2019 |
| Trade Smart Double Glazing Trade Hub Ltd | Construction | 2026 |
| Trailblazer Properties Ltd | Real estate | 2025 |
| Tranquility Base Limited | Extraterritorial | 2009 |
| Transcendent Tarot Limited | Professional & scientific | 2024 |
| Translogi Ltd | Transport & logistics | 2024 |
| Trapasso Luxe Limited | Real estate | 2026 |
| Trenbe UK Limited | Wholesale & retail | 2016 |
| Triple Jump Productions Ltd | Arts & recreation | 2013 |
| Triple U Services Ltd | Professional & scientific | 2021 |
| Triplestrand Limited | Other services | 2008 |
| Trochetia Care Ltd | Health & social care | 2023 |
| Truck and Van Plus Ltd | Wholesale & retail | 2020 |
| True Vision Elite | Arts & recreation | 2021 |