| Touch PAD Limited | Extraterritorial | 2011 |
| Tower Brands Limited | Wholesale & retail | 2025 |
| Towers (Harrogate) Limited | Administrative & support | 2003 |
| Town Taxis Harrogate Limited | Transport & logistics | 2010 |
| Townend Strategic Investments Ltd | Professional & scientific | 2022 |
| Townhouse Design Limited | Wholesale & retail | 2004 |
| Townscape Architects Limited | Professional & scientific | 2007 |
| Toxin Limited | Wholesale & retail | 2022 |
| Toybf Limited | Administrative & support | 2015 |
| Toynado Ltd | Wholesale & retail | 2017 |
| TP Group Projects Limited | Health & social care | 2003 |
| TP4 Projects Ltd | Construction | 2016 |
| TPA Portable Roadways Limited | Extraterritorial | 2001 |
| TPG (Headingley) Ltd | Wholesale & retail | 2020 |
| TPH Marketing Limited | Extraterritorial | 2021 |
| Tpinvestments Ltd | Real estate | 2021 |
| TR Aviation Services Limited | Transport & logistics | 2013 |
| Tracey Limited | Extraterritorial | 2012 |
| Track North Ltd | Professional & scientific | 2025 |
| Trade 4 Tools Ltd | Wholesale & retail | 2020 |
| Trade Brokering Services and Consultancy Limited | Wholesale & retail | 2020 |
| Trade Crew Ltd | Extraterritorial | 2013 |
| Trade Price Stone Ltd | Extraterritorial | 2023 |
| Tradebooker Ltd | Administrative & support | 2017 |
| Traditional Cookers of Yorkshire Limited | Wholesale & retail | 2011 |
| Trainee Driving Academy Ltd | Education | 2019 |
| Training Progress Ltd | Information & communication | 2013 |
| Traklink Ltd | Professional & scientific | 2020 |
| Tramell Group Limited | Extraterritorial | 2025 |
| Transatlantix Ltd | Information & communication | 2023 |
| Transdev Blazefield Limited | Transport & logistics | 1991 |
| Transdev Greater Manchester Limited | Transport & logistics | 2022 |
| Transdev Liverpool City Region Limited | Transport & logistics | 2025 |
| Transdev London Limited | Transport & logistics | 2006 |
| Transdev Northern Blue Limited | Transport & logistics | 1999 |
| Transdev PLC | Transport & logistics | 1992 |
| Transdev Tram UK Limited | Transport & logistics | 1998 |
| Transdev York Limited | Transport & logistics | 2002 |
| Transformation Arena | Other services | 2019 |
| Transformative Limited | Extraterritorial | 2021 |
| Transforming Ninja Limited | Information & communication | 2016 |
| Transit Zero Emissions Limited | Wholesale & retail | 2022 |
| Transport Engineering Support Services Ltd | Transport & logistics | 2003 |
| Transport Zero Emissions Limited | Wholesale & retail | 2022 |
| Trd&Tru Ltd | Professional & scientific | 2019 |
| Treats Hub Limited | Wholesale & retail | 2025 |
| Treble 2 Group Ltd. | Wholesale & retail | 2016 |
| Treenut General Trading Ltd | Administrative & support | 2026 |
| Treeton House Consulting Ltd | Professional & scientific | 2011 |
| Trench Shore Limited | Extraterritorial | 1987 |
| TRG UK Capital Limited | Construction | 2018 |
| TRG UK Developments Limited | Construction | 2018 |
| Tri-Care Limited | Real estate | 1988 |
| Tribal 3D Ltd | Manufacturing | 2011 |
| Tribe Athletic Ltd | Arts & recreation | 2020 |
| Trident-Heritage Limited | Transport & logistics | 2000 |
| Tridesco Ltd | Professional & scientific | 2023 |
| Trig Creative Limited | Professional & scientific | 2004 |
| Trig Point Properties Ltd | Transport & logistics | 2016 |
| Trilam Technology Limited | Professional & scientific | 1990 |
| Trileco Ltd | Wholesale & retail | 2024 |
| Trinity Apparel UK Limited | Wholesale & retail | 2012 |
| Triple X Ltd | Extraterritorial | 2012 |
| Triponel Consulting Ltd | Professional & scientific | 2015 |
| Trison Nominees Limited | Professional & scientific | 2018 |
| Trivelli Limited | Extraterritorial | 2026 |
| Trixe Ltd | Extraterritorial | 2026 |
| Trophy Labs UK Ltd | Professional & scientific | 2026 |
| Trotters (Public House) Ltd | Hospitality | 1992 |
| Troy Management Services Limited | Professional & scientific | 2025 |
| Troy Valentine Limited | Extraterritorial | 2026 |
| TRS Trading and Holding International Limited | Financial services | 2024 |
| Trucoat Ltd | Construction | 2018 |
| Trudi Hannaford Ltd | Administrative & support | 2016 |
| True Delight Equine Ltd | Arts & recreation | 2026 |
| True Fidelity Limited | Other services | 2016 |
| True Mobile TV and Sound Limited | Information & communication | 2014 |
| True Tea Harrogate Ltd | Manufacturing | 2021 |
| True Worth Marketing Limited | Professional & scientific | 2025 |
| Truecut Surgical Ltd | Health & social care | 2026 |
| Trueform Property Services Limited | Households | 2018 |
| Trueform Wellness Ltd | Arts & recreation | 2012 |
| Trueline Engineering Ltd | Manufacturing | 2025 |
| Truesource Nutrition & Coaching Ltd | Wholesale & retail | 2025 |
| Trump Group Limited | Extraterritorial | 2025 |
| Trupay UK Payroll Services Ltd | Professional & scientific | 2021 |
| Trust Collective Limited | Professional & scientific | 2003 |
| Trust Lodgings Ltd | Real estate | 2022 |
| Trustangel Limited | Administrative & support | 2008 |
| Trusted Engineering Ltd | Professional & scientific | 2023 |
| Truth Legal Holdings Limited | Professional & scientific | 2023 |
| Truth Legal Limited | Professional & scientific | 2012 |
| Trux Limited | Extraterritorial | 2011 |
| Trylogic Limited | Extraterritorial | 2025 |
| Tsium Limited | Information & communication | 2010 |
| Tskj Properties Ltd | Real estate | 2017 |
| TSL Convenience Store Limited | Wholesale & retail | 2025 |
| TSW Construction (North) Ltd | Construction | 2024 |
| TTC Services Limited | Professional & scientific | 2016 |
| TTM Agency Limited | Administrative & support | 2022 |