| Top Services MIV Ltd | Construction | 2025 |
| Top Talent Recruit Ltd | Administrative & support | 2024 |
| Top WIN Competitions Ltd | Arts & recreation | 2023 |
| TOP4 Limited | Wholesale & retail | 2020 |
| TOP4 Property's Ltd | Construction | 2021 |
| Topbol Properties Ltd | Real estate | 2024 |
| Topbrass Innovative Ltd | Wholesale & retail | 2025 |
| Topcoat Construction Limited | Construction | 1995 |
| Tope Sales & Consulting Ltd | Professional & scientific | 2025 |
| Topfix Home Improvements Ltd | Construction | 2025 |
| Topknight Properties Limited | Real estate | 2021 |
| Topline Care Services Ltd | Health & social care | 2020 |
| Topline Security Services Ltd | Administrative & support | 2018 |
| Topman Construction Limited | Construction | 2009 |
| Topocad Engineering Limited | Construction | 2024 |
| Topova Ltd | Construction | 2024 |
| Toppex Ltd | Construction | 2019 |
| Torba Building Service Ltd | Construction | 2020 |
| Toreb Limited | Health & social care | 2015 |
| Tornado Express (London East) Ltd | Transport & logistics | 2015 |
| Torsion Services Limited | Construction | 2020 |
| Torvex Limited | Extraterritorial | 2024 |
| Tosh Carpentry Ltd | Construction | 2023 |
| Tosya Construction Ltd | Construction | 2024 |
| Total Equity Ltd | Professional & scientific | 2025 |
| Totaldebtsolutions Ltd | Professional & scientific | 2025 |
| Totus Services Ltd | Construction | 2022 |
| Touch Care Agency Ltd | Administrative & support | 2020 |
| Touch Medical Ltd | Health & social care | 2020 |
| Touchstone Residential Ltd | Construction | 2023 |
| Toughforce Services Limited | Financial services | 2018 |
| Tour DE Britain Limited | Wholesale & retail | 2017 |
| Tourinn Escapes Ltd | Administrative & support | 2022 |
| Tourlousse Painting and Decorating Limited | Construction | 2020 |
| Tower Bridge Properties Limited | Real estate | 2012 |
| Tower Joinery Solutions Ltd | Construction | 2019 |
| Tower Real Estate Management Ltd | Real estate | 2017 |
| Town & Country Lodge Limited | Real estate | 2025 |
| Toyayind Investment Limited | Real estate | 2026 |
| Toyin Properties Limited | Real estate | 2019 |
| Toyowrites Ltd | Arts & recreation | 2020 |
| Toys Garden Limited | Wholesale & retail | 2021 |
| Toys Plus More Ltd | Wholesale & retail | 2023 |
| TP Couture Ltd | Manufacturing | 2025 |
| TP Telecoms Limited | Information & communication | 2017 |
| Tpl-Landscapes Ltd | Professional & scientific | 2025 |
| TQ Financial Limited | Professional & scientific | 2012 |
| TQQ Ltd | Manufacturing | 2014 |
| TR Sash Windows Limited | Construction | 2025 |
| Traceproperty Tech Ltd | Information & communication | 2026 |
| Trade Hub Group of Companies Limited | Financial services | 2026 |
| Trade Rapid Construction Ltd | Construction | 2025 |
| Trade Safety Limited | Extraterritorial | 2004 |
| Trade Tapes Limited | Wholesale & retail | 2024 |
| Traded Risk Associates Limited | Professional & scientific | 2013 |
| TRADEDIRECTUK9 Limited | Real estate | 2019 |
| Trademen Ltd | Construction | 2026 |
| Traders Group Ltd | Wholesale & retail | 2025 |
| Traders Portal Limited | Wholesale & retail | 2026 |
| Tradesource Distribution Ltd | Wholesale & retail | 2023 |
| Tradex Link UK Ltd | Wholesale & retail | 2024 |
| Tradezio Ltd | Wholesale & retail | 2026 |
| Trading AG Ltd | Wholesale & retail | 2023 |
| Tradingcourse Ltd | Professional & scientific | 2025 |
| Trae Armani Estates Ltd | Real estate | 2025 |
| Traffiq Ltd | Wholesale & retail | 2018 |
| Train the Trade Ltd | Administrative & support | 2024 |
| Trajan Limited | Real estate | 2026 |
| Tranquilhaven Living Care UK Limited | Administrative & support | 2024 |
| Trans City Car Centre Limited | Wholesale & retail | 1996 |
| Trans Hofman Ltd | Transport & logistics | 2024 |
| Trans Luca Ltd | Transport & logistics | 2026 |
| Transcendaire Stays Limited | Real estate | 2026 |
| Transervice FR Ltd | Transport & logistics | 2018 |
| Translations 123 Ltd | Professional & scientific | 2018 |
| Transport Anywhere Limited | Transport & logistics | 2019 |
| Transport ENG Ltd | Construction | 2025 |
| Transwell Capital Ltd | Wholesale & retail | 2021 |
| Trasam Holdings Limited | Financial services | 2013 |
| Trava Construction Ltd | Construction | 2024 |
| Travel Borders Ltd | Administrative & support | 2024 |
| Travel Brothers Limited | Administrative & support | 2019 |
| Travel for FUN Ltd | Administrative & support | 2019 |
| Travel Planet Limited | Administrative & support | 2018 |
| Traveluxury Limited | Administrative & support | 2024 |
| Travin Hospitality UK Ltd | Administrative & support | 2025 |
| Traypan Private Ltd | Professional & scientific | 2023 |
| Tre-T Food Hub Ltd | Hospitality | 2026 |
| Treasure Builds Ltd | Construction | 2023 |
| Treasures Titan Ltd | Wholesale & retail | 2021 |
| Treats by Bisbis Ltd | Hospitality | 2024 |
| Treats Delicious Ltd | Wholesale & retail | 2024 |
| Trebled Ltd | Wholesale & retail | 2019 |
| Trees Hotel Ltd | Hospitality | 2019 |
| Trefl UK Ltd | Extraterritorial | 2023 |
| Trehaven Management Limited | Real estate | 2016 |
| Tremendous Films Limited | Information & communication | 2006 |
| Trench Doctor Water Utilities Ltd | Construction | 2009 |
| Trend Expert Services Limited | Wholesale & retail | 2026 |
| Trendhubb Ltd | Other services | 2023 |