| TSL Leasing Limited | Administrative & support | 2017 |
| TSL Secretarial Services Ltd | Administrative & support | 2017 |
| TSL Turton (2014) Ltd | Manufacturing | 2014 |
| TSM Toll Bar Limited | Manufacturing | 2014 |
| Tsmc Sales Ltd | Professional & scientific | 2021 |
| TSR Clothing Ltd | Wholesale & retail | 2025 |
| TSS Carter Limited | Administrative & support | 2022 |
| TSS Consult Limited | Real estate | 2012 |
| Tsuki Global Limited | Hospitality | 2022 |
| Tsuri Stays Ltd | Real estate | 2025 |
| TSV Corp Ltd | Real estate | 2026 |
| TSW Incorporated Limited | Wholesale & retail | 2021 |
| TT Cleaning Ltd | Administrative & support | 2021 |
| TT Plant and Haulage Ltd | Transport & logistics | 2021 |
| TT Shoes Ltd | Wholesale & retail | 2023 |
| TT Tech Plumbing & Heating Services Ltd | Construction | 2025 |
| TTB CLG Ltd | Administrative & support | 2025 |
| TTB Electrical Limited | Manufacturing | 2016 |
| TTG Holdings Limited | Financial services | 2017 |
| TTL Regent Court Limited | Real estate | 2017 |
| TTL3 Limited | Information & communication | 2021 |
| TTS Car Sales Limited | Wholesale & retail | 2003 |
| TTS Precision Engineering Ltd | Manufacturing | 2010 |
| TTS Property Holdings Ltd | Financial services | 2020 |
| Ttwc Beauty Products Limited | Wholesale & retail | 2013 |
| TU Associates UK Limited | Wholesale & retail | 2020 |
| TU Go Services Ltd | Construction | 2024 |
| Tube Television Ltd | Manufacturing | 2016 |
| Tubiz Global Ltd | Transport & logistics | 2022 |
| Tubr Ltd | Professional & scientific | 2020 |
| Tuck in of Shefield Limited | Hospitality | 2025 |
| Tucker & Goose Limited | Information & communication | 2009 |
| Tudakuda Ltd | Health & social care | 2017 |
| Tudor Group Northwest Limited | Construction | 2017 |
| Tudor Hydrotherapy Limited | Health & social care | 2017 |
| Tudor Stone Limited | Manufacturing | 2016 |
| Tudor Treadmills Limited | Manufacturing | 2009 |
| Tudorstone Holdings Limited | Professional & scientific | 2003 |
| TUE Liveries Limited | Agriculture & fishing | 2011 |
| Tufan MAY Ltd | Wholesale & retail | 2025 |
| Tufan Property Investment Ltd | Real estate | 2026 |
| Tufcot Engineering Limited | Manufacturing | 1981 |
| Tuftingaround Limited | Manufacturing | 2025 |
| Tufts Limited | Wholesale & retail | 1998 |
| Tuktak Ltd | Information & communication | 2021 |
| Tulej Construction Limited | Construction | 2025 |
| Tulia Holdings Ltd | Financial services | 2025 |
| Tulip Properties Limited | Real estate | 1989 |
| Tullio Ltd | Other services | 2021 |
| Tulsiihb Ltd | Other services | 2025 |
| Tuluh Ltd | Health & social care | 2015 |
| Tuluhow Ltd | Health & social care | 2022 |
| Tummy Tonics Ltd | Hospitality | 2018 |
| Tune ME UP Ltd | Hospitality | 2024 |
| Tungspeed Alloys Limited | Water & waste | 2026 |
| Tunnel TAP Limited | Manufacturing | 2021 |
| Tuos Parking Limited | Transport & logistics | 2013 |
| Tupholme Logic Limited | Professional & scientific | 2015 |
| Turbo Truck Ltd | Transport & logistics | 2019 |
| Turbocare 24 Limited | Wholesale & retail | 2020 |
| Turbomotive Limited | Professional & scientific | 2015 |
| Turker Construction Ltd | Construction | 2020 |
| Turkish Barber (Beighton) Ltd | Other services | 2026 |
| Turkish Barber Ecclesfield Limited | Other services | 2024 |
| Turkish Baths 1877 Ltd | Other services | 2023 |
| Turn IT UP Ltd | Information & communication | 2018 |
| Turner Lambert Limited | Construction | 2015 |
| Turner Property Investments Limited | Construction | 2005 |
| Turnerround Ltd | Real estate | 2017 |
| Turnerround Partnership LLP | | 2025 |
| Turners(Crosspool)Limited | Real estate | 1948 |
| Turnshaw Property Developments Ltd | Construction | 2020 |
| Turpin Thomson Sculpture Ltd | Arts & recreation | 2023 |
| Turris Corvo Productions Ltd | Administrative & support | 2019 |
| Turtledove Cyber Limited | Information & communication | 2026 |
| Turton Plumbing & Heating Limited | Construction | 2023 |
| Turtonhurst Limited | Real estate | 1984 |
| Turvers Limited | Wholesale & retail | 2002 |
| Tusaale CIC | Education | 2025 |
| TUSIMA0720 Omutonzi Limited | Health & social care | 2015 |
| Tusitala Haus Limited | Information & communication | 2023 |
| Tusker Resources Limited | Mining & quarrying | 2019 |
| TUTOR101 Ltd | Education | 2023 |
| Tutora Ltd | Education | 2014 |
| Tutorful Limited | Professional & scientific | 2017 |
| Tuxtel Ltd | Information & communication | 2008 |
| TV and Film Cars.Com Limited | Other services | 2011 |
| TW Anaesthesia Limited | Health & social care | 2017 |
| TW Hospitality Limited | Hospitality | 2025 |
| TW Insight (Britain in Focus) Limited | Professional & scientific | 2024 |
| TW Productions Limited | Information & communication | 2018 |
| TW Surfacing Ltd | Construction | 2021 |
| TW Testing Solutions Limited | Professional & scientific | 2020 |
| Twangtastic Limited | Information & communication | 2024 |
| Twangy Guitar Music Ltd | Arts & recreation | 2012 |
| Twani Ltd | Information & communication | 2024 |
| Twayblade Ltd | Professional & scientific | 2021 |
| Tweedy Clothing Ltd | Wholesale & retail | 2019 |
| Tweeze Limited | Other services | 2014 |
| Twelve Plus 12 Recovery Ltd | Wholesale & retail | 2025 |