| T&K Nowak Services Ltd | Wholesale & retail | 2015 |
| T&K Solar Installers Ltd | Construction | 2025 |
| T&T Logistics Limited | Administrative & support | 2025 |
| T&T Paint Services Ltd | Manufacturing | 2025 |
| T&T Stamford Ltd | Wholesale & retail | 2026 |
| T'Ayce of PIE Entertainment Limited | Arts & recreation | 2011 |
| T-Hill Limited | Information & communication | 2023 |
| T. Whyatt & SON Ltd | Arts & recreation | 2013 |
| T.A.H. Electrical Engineers Limited | Construction | 1996 |
| T.B Drivserv Ltd | Transport & logistics | 2021 |
| T.Bogdan-Trans Ltd | Transport & logistics | 2014 |
| T.G.M Serviced Apartment Limited | Households | 2024 |
| T.J.A.R Properties Limited | Real estate | 2026 |
| T.R Morton Ltd | Construction | 2026 |
| T.Rex Design Limited | Administrative & support | 2004 |
| T.T.Drive Ltd | Transport & logistics | 2025 |
| T2 Surveying Limited | Construction | 2010 |
| T4A Limited | Wholesale & retail | 2018 |
| T4TRAINING Ltd | Professional & scientific | 2025 |
| T5 DMS Ltd | Professional & scientific | 2024 |
| T5 Homes Ltd | Real estate | 2023 |
| T7 Property Development Ltd | Real estate | 2024 |
| Tackamore Limited | Information & communication | 2024 |
| Tacos and Flipflops Ltd | Hospitality | 2024 |
| Tactical KIT Limited | Wholesale & retail | 2011 |
| Tactical Property Group Ltd | Hospitality | 2025 |
| Taddy Ltd | Transport & logistics | 2013 |
| Tadpole Garden Village C.I.C. | Households | 2014 |
| Taeillo Ltd | Wholesale & retail | 2022 |
| Taemo Holdings Limited | Real estate | 2024 |
| TAF Comms Ltd | Administrative & support | 2016 |
| Taffstreet Limited | Professional & scientific | 2026 |
| Taggi Limited | Wholesale & retail | 2024 |
| Tahir Iqbal Properties Ltd | Real estate | 2021 |
| Tahir Khan Consultancy Limited | Professional & scientific | 2024 |
| Tahmuda Group Ltd | Wholesale & retail | 2026 |
| Taiba Traders Ltd | Wholesale & retail | 2024 |
| Tail & INK Ltd | Wholesale & retail | 2025 |
| Tailor & Cutter (Cambridge) Limited | Manufacturing | 2006 |
| Tailor & Cutter Limited | Extraterritorial | 2006 |
| Tailor Made Financial Ltd | Financial services | 2003 |
| Tailored Personnel Services Ltd | Administrative & support | 2021 |
| Tajik Limited | Hospitality | 2025 |
| TAK Security Services Ltd | Administrative & support | 2025 |
| Takeorders Ltd | Information & communication | 2020 |
| Takhus Limited | Information & communication | 2024 |
| Taktiko Services Limited | Professional & scientific | 2026 |
| Talat Motors Ltd | Wholesale & retail | 2026 |
| Talent Embassy Limited | Administrative & support | 2025 |
| Talent Integration Ltd | Administrative & support | 2014 |
| Talent Junkie Ltd | Administrative & support | 2023 |
| Talent Partnership Group Ltd | Administrative & support | 2025 |
| Talicha London Ltd | Wholesale & retail | 2011 |
| Taline Limited | Mining & quarrying | 2023 |
| Talk Mortgage Broker Ltd | Financial services | 2011 |
| Talking Buildings Ltd | Professional & scientific | 2024 |
| Talking Dogs Limited | Administrative & support | 2002 |
| Talking Heads Hair Studio Limited | Other services | 2002 |
| Tall Productions Ltd | Information & communication | 2022 |
| Tallawah Group Limited | Administrative & support | 2025 |
| Talverra Ltd | Information & communication | 2025 |
| Taman Holdings Ltd | Financial services | 2024 |
| Tamar Associates Limited | Wholesale & retail | 2026 |
| Tamco Holdings Ltd | Financial services | 2024 |
| Tamerlan Transport Ltd | Transport & logistics | 2016 |
| Tamila Transport Limited | Transport & logistics | 2025 |
| Tamney Healthcare Ltd | Health & social care | 2023 |
| Tamoh OBY Ltd | Real estate | 2022 |
| Tamts Limited | Health & social care | 2018 |
| Tamweb Ltd | Administrative & support | 2014 |
| TAN & Glow Beauty Ltd | Other services | 2023 |
| Tan-Y-Bryn Ltd | Financial services | 2021 |
| Tanalicious Ltd | Other services | 2024 |
| Tanatee Ltd | Health & social care | 2018 |
| Tandee & Van DEN Berk Nurseries Limited | Administrative & support | 2024 |
| Tandee Landscaping Ltd | Wholesale & retail | 2016 |
| Tandem Payroll Ltd | Professional & scientific | 2015 |
| Taner ZOR Ltd | Information & communication | 2025 |
| Tanever Solutions Ltd | Information & communication | 2012 |
| Tangara Services and Investments Limited | Information & communication | 2025 |
| Tangerine Capital Ltd | Real estate | 2024 |
| Tangl Electrical Ltd | Construction | 2026 |
| Tango Group International Ltd | Manufacturing | 1998 |
| Tango Group Intl Sales Ltd | Manufacturing | 1957 |
| Tania Optical Ltd | Health & social care | 2025 |
| Tannery Mews Freehold Company Limited | Households | 2008 |
| Tansor Court Limited | Real estate | 2013 |
| Tanvir Properties Ltd | Real estate | 2021 |
| Tanyak Ltd | Health & social care | 2025 |
| Tanzii TV C.I.C. | Education | 2021 |
| TAP & Kitchen Limited | Hospitality | 2014 |
| TAP the Table Cooperative Ltd | Arts & recreation | 2011 |
| Tapia Developments Ltd | Construction | 2020 |
| Tapia Investments Limited | Real estate | 2012 |
| Tapscott Installations Limited | Construction | 2010 |
| Tapti Solutions Ltd | Information & communication | 2017 |
| Tara Bespoke Ltd | Wholesale & retail | 2025 |
| Tara Suchak Ltd | Health & social care | 2023 |
| Taralin Property Refurbishment Ltd | Construction | 2026 |
| Tarbush Limited | Wholesale & retail | 2024 |