| Traditional World Ltd | Wholesale & retail | 2026 |
| Train Talent Limited | Education | 2023 |
| Training CPC Ltd | Transport & logistics | 2023 |
| Trans Cornel Ltd | Transport & logistics | 2023 |
| Transco Group Roadways Limited | Construction | 2024 |
| Transit 2017 Limited | Administrative & support | 2017 |
| Transnation Limited | Transport & logistics | 2023 |
| Transport Driver Limited | Transport & logistics | 2018 |
| Trent Lifting Limited | Construction | 2008 |
| Trent Refractories Holdings Limited | Financial services | 2017 |
| Trent Supplies Limited | Wholesale & retail | 2006 |
| Trent Transport Solutions Ltd | Transport & logistics | 2014 |
| Trent Valley Electrical Services Limited | Construction | 2018 |
| Trent Valley Maintenance Limited | Construction | 2001 |
| Trent Valley Refrigeration Limited | Manufacturing | 2002 |
| Trenta Restaurant Ltd | Hospitality | 2016 |
| Trentside Capital Limited | Financial services | 2021 |
| Trentside Engineering Limited | Manufacturing | 2013 |
| TRI Industrial Services Limited | Manufacturing | 2009 |
| Trilogy Automotive Limited | Wholesale & retail | 2023 |
| Trimoiria Holdings Ltd | Financial services | 2026 |
| Trinity GP Limited | Health & social care | 2020 |
| Trinity Medical Holdings Limited | Financial services | 2022 |
| Trinity Private Practice Management Limited | Administrative & support | 2022 |
| Triple a Children Residential Homes Limited | Health & social care | 2026 |
| Triple a Group and Holdings Limited | Financial services | 2026 |
| Triple a Homes and Properties Limited | Real estate | 2026 |
| Triple a Tiny Tots Limited | Health & social care | 2024 |
| Triple L Care Services Limited | Public administration | 2019 |
| Triple M Estates Ltd | Real estate | 2025 |
| TRM Talent Group Limited | Administrative & support | 2024 |
| Trojan Events Ltd | Arts & recreation | 2023 |
| Trotters Holdings Limited | Financial services | 2021 |
| Troys Property Limited | Real estate | 2025 |
| Truck-Tech (UK) Limited | Wholesale & retail | 1999 |
| Truckscan Ltd | Transport & logistics | 2026 |
| True North Alternative Provision CIC | Education | 2025 |
| Truecast 2025 Ltd | Financial services | 2025 |
| Tsang Surgical Limited | Health & social care | 2013 |
| TSB Roofing Limited | Construction | 2008 |
| TSG Group Ltd | Hospitality | 2026 |
| TSR Prop Co Limited | Real estate | 2024 |
| Ttarius Ltd | Wholesale & retail | 2023 |
| Ttlt Limited | Wholesale & retail | 2023 |
| Ttouch Autohaus Limited | Wholesale & retail | 2025 |
| TTS Support Limited | Manufacturing | 2010 |
| Tuatara Limited | Financial services | 2021 |
| Tuber Group Limited | Professional & scientific | 2021 |
| Tuberosity Ltd | Health & social care | 2014 |
| Tudor Cleaner 24 Ltd | Administrative & support | 2025 |
| Tudorel Transport Ltd | Transport & logistics | 2023 |
| Tudor’S Food Limited | Wholesale & retail | 2025 |
| Tulo Ltd | Transport & logistics | 2021 |
| Turfstore Ltd | Extraterritorial | 2022 |
| Turnbullanaesthesia Limited | Health & social care | 2021 |
| Turtustrends Limited | Wholesale & retail | 2025 |
| Tuscan Spring Limited | Health & social care | 2022 |
| Tutam Event Solutions Limited | Administrative & support | 2025 |
| Tutam FM Ltd | Administrative & support | 2022 |
| Tutam Group Limited | Financial services | 2023 |
| Tutor-Me Education Ltd | Education | 2022 |
| TVM Building & Plumbing Services Limited | Construction | 2022 |
| Twenty 20 Property Services Ltd | Households | 2024 |
| Twilight Auto Repairs Limited | Wholesale & retail | 2011 |
| TWISTED29 Limited | Information & communication | 2018 |
| Two Boys Developments Limited | Construction | 2018 |
| Two Boys Rental Homes Limited | Real estate | 2018 |
| Tyaas Swan Ltd | Wholesale & retail | 2023 |
| Tyma Solutions Ltd | Construction | 2025 |
| Tyrerite Scunthorpe Limited | Wholesale & retail | 2010 |
| Tyson Constructionn Ltd | Construction | 2025 |
| Tyto Property & Probate Lawyers Ltd | Professional & scientific | 2024 |
| Uddin Group Ltd | Real estate | 2024 |
| Udin Limited | Wholesale & retail | 2025 |
| UE Property Management Ltd | Real estate | 2022 |
| UK Barber 25 Ltd | Other services | 2025 |
| UK Best Grill Ltd | Hospitality | 2025 |
| UK Best Kebab Ltd | Hospitality | 2024 |
| UK Energy Advisory Ltd | Professional & scientific | 2025 |
| UK Global Auto Ltd | Wholesale & retail | 2021 |
| Ukalala Limited | Information & communication | 2025 |
| Ukvape Ltd | Manufacturing | 2018 |
| Ulinic Trans Ltd | Transport & logistics | 2019 |
| Ultimate Doors Limited | Construction | 2016 |
| Ultimate Gaming Ltd | Administrative & support | 2015 |
| Ultimate Hand Carwash Limited | Other services | 2020 |
| Ultimate Performance Scunthorpe Ltd | Other services | 2019 |
| Ultimate Property Holdings Limited | Real estate | 2019 |
| Ultra Electrical Ltd | Construction | 2018 |
| Ultra Technology Solutions Ltd | Information & communication | 2017 |
| Umg-Cargo Ltd | Transport & logistics | 2024 |
| Unison Alliance Ltd | Professional & scientific | 2022 |
| United Merchant Bar Limited | Manufacturing | 2016 |
| United Roots Community CIC | Education | 2026 |
| Universal Commercial Truck Ltd | Wholesale & retail | 2021 |
| Universal Trade Publications Limited | Information & communication | 2001 |
| Unwins Engineering Services Ltd | Manufacturing | 2016 |
| Uppercrust (Scunthorpe) Limited | Hospitality | 2014 |
| Urang Limited | Real estate | 2022 |
| Urban Feather Ltd | Information & communication | 2005 |