| Tkfc Ltd | Hospitality | 2023 |
| TKH Services Limited | Professional & scientific | 2016 |
| TKK (UK) Limited | Hospitality | 2014 |
| Tkmk & Co LLP | | 2021 |
| Tkml Limited | Hospitality | 2016 |
| TLJ Property Services Limited | Real estate | 2017 |
| TM Mcdaniel Limited | Information & communication | 2017 |
| TM. Ajac Ltd | Real estate | 2021 |
| Tmcuk Car Sales Ltd | Wholesale & retail | 2017 |
| Tmeg Holdings Limited | Real estate | 2026 |
| Tmeg Management Limited | Professional & scientific | 2015 |
| TMG Electrical Engineers Ltd | Construction | 2013 |
| Tmic Limited | Wholesale & retail | 2009 |
| Tmld Solutions Ltd | Construction | 2018 |
| Tmlm Holdings Limited | Financial services | 2018 |
| Tmlm Investments Limited | Real estate | 2020 |
| Tmsoe Limited | Education | 2005 |
| TNG Office Ltd | Professional & scientific | 2018 |
| TNS London Limited | Wholesale & retail | 2006 |
| Tnthomesuk Ltd | Real estate | 2023 |
| Tobacco Dock Corporation Limited | Extraterritorial | 2011 |
| Toby Organ Limited | Construction | 2018 |
| Tocas Property Limited | Construction | 2015 |
| TOG Utilities Ltd | Wholesale & retail | 2026 |
| Toggle Jobs Limited | Information & communication | 2019 |
| Tokus Consulting Services Ltd | Administrative & support | 2016 |
| Tokus Investment Ltd | Real estate | 2022 |
| TOM Child Garden Landscapes Limited | Administrative & support | 2012 |
| Tony Construct Ltd | Construction | 2018 |
| Toolman Media Limited | Professional & scientific | 2026 |
| Top Crop Limited | Manufacturing | 2020 |
| Top Cyber Security Ltd. | Information & communication | 2023 |
| Top DEC Painting Ltd | Construction | 2022 |
| Top Flight Services Ltd | Construction | 2018 |
| Top Garments Ltd | Wholesale & retail | 2013 |
| Top London Gift Ltd | Wholesale & retail | 2019 |
| Top Mark Management Consultancy Limited | Professional & scientific | 2016 |
| Top of the Avenue Ltd | Administrative & support | 2022 |
| Top Ride Services Ltd | Transport & logistics | 2024 |
| Top Tier Global Limited | Real estate | 2015 |
| Topcarwash Ltd | Administrative & support | 2019 |
| Topcret UK Ltd | Administrative & support | 2014 |
| Topfi UK Ltd | Administrative & support | 2024 |
| Topflow Services Ltd | Construction | 2019 |
| Topline Growth Solutions Ltd | Professional & scientific | 2026 |
| Tops Developments Limited | Construction | 2020 |
| Tops Property Ltd | Real estate | 2022 |
| Tops Sutton Limited | Hospitality | 2023 |
| Topspec Property Services Ltd | Construction | 2018 |
| Topstore Limited | Wholesale & retail | 2020 |
| Toptam Ltd | Wholesale & retail | 2016 |
| Torbett Golf Limited | Arts & recreation | 2009 |
| Torera House Limited | Manufacturing | 2024 |
| Torino Trading Company Ltd | Wholesale & retail | 2025 |
| Toros Advisory Limited | Professional & scientific | 2022 |
| Torque Dynamics Ltd | Information & communication | 2024 |
| Torque Hire Tools Limited | Administrative & support | 2025 |
| Total Build Solutions & Carpentry Ltd | Construction | 2025 |
| Totalpost Mailing and Mechanisation Ltd | Other services | 1985 |
| Toucan SET Ltd | Manufacturing | 2021 |
| Toucan Staging Ltd | Manufacturing | 2020 |
| Tour Designers (UK) Ltd | Administrative & support | 2006 |
| Tovia Properties Limited | Real estate | 2024 |
| Tower BC Limited | Financial services | 2009 |
| Tower Bridge Trading Ltd | Professional & scientific | 2018 |
| Tower Vent Services Ltd | Construction | 2023 |
| Town Chicken and Pizza ( Food ) Limited | Hospitality | 2018 |
| Townhead 17 Limited | Real estate | 2019 |
| TPF Associates Limited | Real estate | 2004 |
| TPG 1 Development Ltd | Construction | 2025 |
| Tracescent Limited | Real estate | 1999 |
| Trade County Limited | Water & waste | 2023 |
| Trade Tiles Direct Ltd | Construction | 2017 |
| Tradesman Saver Limited | Professional & scientific | 2008 |
| Tradezone (South East) Limited | Construction | 2004 |
| Traleda Construction Limited | Construction | 1972 |
| Tranmar (UK) Limited | Extraterritorial | 2015 |
| Trans Tech Speed Limited | Transport & logistics | 2019 |
| Transitus Holdings Ltd | Financial services | 2025 |
| Transworld Linguists Services Limited | Administrative & support | 1996 |
| Tranter Webb Limited | Real estate | 2010 |
| Trap Wings Ltd | Hospitality | 2025 |
| Tratexcore Ltd | Wholesale & retail | 2020 |
| TRC Truck Rental Limited | Administrative & support | 2003 |
| Treadwell Electrical Limited | Construction | 2024 |
| Tree Star Care & Maintenance Ltd | Administrative & support | 2018 |
| Tree Star Maintenance Ltd | Administrative & support | 2014 |
| Treehouse Property Management Services Ltd | Administrative & support | 2016 |
| Trematon Place (Broom Road) Teddington Residents Association Limited | Households | 1991 |
| Trematon Place (Freeholders) Limited | Households | 1997 |
| Trenchards Auctioneers & Valuers Ltd | Wholesale & retail | 2025 |
| Trend CUT Ltd | Other services | 2018 |
| Trendmark Engineering Limited | | 1987 |
| Trent Smart Solutions Ltd | Manufacturing | 2016 |
| Trevanion Holdings Ltd | Financial services | 2025 |
| Trevi Home Limited | Wholesale & retail | 2017 |
| Trevi Investments Limited | Real estate | 2018 |
| Trezured Ltd | Information & communication | 2019 |
| Triados Ltd | Wholesale & retail | 2024 |
| Triasset Commercial Limited | Real estate | 2022 |