| Tpsff Holdings Limited | Professional & scientific | 2008 |
| Trace Consultancy Limited | Information & communication | 2008 |
| Traction HR Consulting Limited | Professional & scientific | 2025 |
| Trademark-Removals Ltd | Transport & logistics | 2025 |
| Trafalgar Personal Developments Ltd | Education | 2009 |
| Train of Thought Consultants Limited | Professional & scientific | 2025 |
| Training With Toddy Ltd | Education | 2024 |
| Trans-Meridian Trading Limited | Wholesale & retail | 2023 |
| Transland Estates Limited | Real estate | 2020 |
| Transland Limited | Real estate | 2018 |
| Translok Limited | Transport & logistics | 2017 |
| Transport Compliance App Limited | Professional & scientific | 2024 |
| Travel Narratives Ltd | Professional & scientific | 2026 |
| TRB Lightweight Structures America Ltd | Manufacturing | 2019 |
| TRB Lightweight Structures Limited | Manufacturing | 1989 |
| TRB Technology Group Limited | Professional & scientific | 2007 |
| TRC Property Development Limited | Real estate | 2026 |
| Treative Ltd | Wholesale & retail | 2020 |
| Trebes Consulting Limited | Professional & scientific | 2014 |
| Trebes Management Consultancy Limited | Administrative & support | 2018 |
| Trebes Property Lettings Limited | Real estate | 2024 |
| Treleaven Jones BTL One Ltd | Real estate | 2025 |
| Treleaven Jones Limited | Real estate | 2015 |
| Trenton Box Company Limited | Manufacturing | 2004 |
| Treyarnon LAB Services Limited | Professional & scientific | 2017 |
| Triad SRW Limited | Arts & recreation | 2025 |
| Trime (UK) Limited | Manufacturing | 2016 |
| Trinity & Associates Ltd | Extraterritorial | 2024 |
| Trinity Invest Limited | Construction | 2019 |
| Trinity Waste Solutions Ltd | Water & waste | 2026 |
| Trion Advisory & Management Ltd | Financial services | 2023 |
| Triple G Property Limited | Real estate | 2026 |
| Triple Home Care Limited | Health & social care | 2012 |
| Triple Home Premium Care Limited | Health & social care | 2026 |
| Triple R Commercial Ltd | Financial services | 2019 |
| Triple R Composites Ltd | Manufacturing | 2013 |
| Triquettra Limited | Manufacturing | 2011 |
| Triune Technologies Limited | Professional & scientific | 2006 |
| True Cosmetics Ltd | Wholesale & retail | 2025 |
| True Health Clinics Unlimited | Health & social care | 2009 |
| True Lazer Ltd | Manufacturing | 2025 |
| Trustlane Motors Limited | Construction | 2025 |
| Truth Health Care Services Ltd | Health & social care | 2023 |
| TS Track Solutions Ltd | Professional & scientific | 2020 |
| Tsourous Ferrer Financial Ltd | Financial services | 2026 |
| TT Grooming Room Ltd | Other services | 2022 |
| TTI Distribution Limited | Extraterritorial | 2014 |
| Ttid Limited | Extraterritorial | 2014 |
| Tufted Textiles Ltd | Manufacturing | 2025 |
| Tug-Wi Ltd | Health & social care | 2023 |
| Tulasa & Sons Ltd | Hospitality | 2025 |
| Turbine Works and Technical Support Ltd | Professional & scientific | 2013 |
| Turner Penny Ltd | Financial services | 2022 |
| Tutoruk Limited | Education | 2017 |
| TWD Trading Ltd | Real estate | 2014 |
| Twentysevenshop Ltd | Wholesale & retail | 2020 |
| Twice S & Co Ltd | Health & social care | 2014 |
| Twin Blade Barbers Ltd | Other services | 2023 |
| Twin Peaks Holdings Ltd | Professional & scientific | 2025 |
| Twinkle Stars Limited | Education | 2009 |
| Twist Consultants (UK) Limited | Professional & scientific | 2006 |
| Twist Tech Ltd | Construction | 2025 |
| Twisters Gymnastics Club Ltd | Education | 2019 |
| Twootz.Com Limited | Wholesale & retail | 2011 |
| TWT Consulting Ltd | Information & communication | 2019 |
| TYC Construction Ltd | Construction | 2026 |
| Tyre Bay Direct Limited | Professional & scientific | 2017 |
| U P Publications Limited | Manufacturing | 2003 |
| UA Transport Services Ltd | Transport & logistics | 2019 |
| UAZ Contracts Ltd | Construction | 2022 |
| Ubuntu AI Studios Ltd | Information & communication | 2025 |
| UK Agriculture Limited | Wholesale & retail | 2018 |
| UK Amenity Limited | Agriculture & fishing | 2009 |
| UK Carpentry and Building Ltd | Construction | 2021 |
| UK Education Research and Innovation Limited | Education | 2011 |
| UK Fire Protection Services Ltd | Professional & scientific | 1996 |
| UK Kids Golf Ltd | Arts & recreation | 2010 |
| UK RST Ltd | Transport & logistics | 2022 |
| UK Swim Academy Ltd | Education | 2026 |
| Ulciscor Ltd | Administrative & support | 2004 |
| ULG Group Ltd | Other services | 2023 |
| Underpin Consultants Limited | Professional & scientific | 2019 |
| Underwood Contractors Ltd | Agriculture & fishing | 2006 |
| Underwood the Jewellers Limited | Wholesale & retail | 2026 |
| Unearthed Academy Ltd | Education | 2024 |
| Unearthedbyerin Ltd | Other services | 2024 |
| Unilase Ltd | Manufacturing | 2013 |
| Unique Air Design Ltd | Administrative & support | 2016 |
| Unique Grilled Ltd | Hospitality | 2019 |
| Unique Leisure Limited | Hospitality | 2009 |
| Unirays Limited | Administrative & support | 2008 |
| Unit 07 Boxing Club Ltd | Arts & recreation | 2025 |
| United Foods Direct Limited | Wholesale & retail | 2009 |
| United Shipping Solutions Ltd | Transport & logistics | 2025 |
| United Sound of House Limited | Extraterritorial | 2012 |
| United Sounds of House (Records) Limited | Extraterritorial | 2012 |
| Unity Way Care Services Limited | Health & social care | 2026 |
| Unitycare Network Ltd | Health & social care | 2025 |
| Universal Baby Travel Ltd | Administrative & support | 2025 |
| Universal Pro Ltd | Administrative & support | 2020 |