| THIRTEEN20 Ltd | Transport & logistics | 2023 |
| Thism Ltd | Hospitality | 2025 |
| Thomas Gameson & Sons,Limited | Manufacturing | 1900 |
| Thompson Investing Ltd | Construction | 2023 |
| Thornhill Enterprises Limited | Financial services | 2020 |
| Thriving Capital Ltd | Financial services | 2025 |
| Tian MA Global Investments Limited | Professional & scientific | 2010 |
| Tidy Tails Dog Grooming Limited | Other services | 2024 |
| Tiggs (Shropshire) Ltd | Professional & scientific | 2023 |
| Tile Tech (Coventry) Limited | Construction | 2017 |
| Timbermate Garden Rooms Ltd | Manufacturing | 2026 |
| Timmins Design Limited | Professional & scientific | 2025 |
| Timmys Fastfood Ltd | Hospitality | 2021 |
| Tints Windows Limited | Construction | 2024 |
| Tiny Star Productions Ltd | Professional & scientific | 2023 |
| Tishas Hair and Beauty Supplies Limited | Other services | 2012 |
| Tisma Limited | Extraterritorial | 2013 |
| Titan Steel Trading Limited | Wholesale & retail | 2022 |
| TK Plastering Limited | Construction | 2025 |
| TLC Property Care Ltd | Construction | 2024 |
| TMA Property Investments Limited | Real estate | 2020 |
| TMA Property Maintenance Limited | Construction | 2018 |
| TMA Property Services Limited | Households | 2024 |
| TMA Scaffolding Limited | Construction | 2024 |
| TMC Build Ltd | Construction | 2019 |
| Tmh-Ja Ltd | Households | 2025 |
| TMS Insulations Ltd | Construction | 2023 |
| TNB Consultants Limited | Health & social care | 2025 |
| TNM Plastics Limited | Wholesale & retail | 2013 |
| TNT Homes & Refurbishments Ltd | Wholesale & retail | 2023 |
| TNT Properties (Rugeley) Limited | Construction | 2021 |
| Toby Autos Ltd | Wholesale & retail | 2023 |
| Toby Properties Ltd | Real estate | 2019 |
| Tobyexcel Limited | Professional & scientific | 2024 |
| Tollcomms Ltd | Other services | 2023 |
| TOM Farmer Ltd | Construction | 2024 |
| Toma Homes Limited | Real estate | 2018 |
| Tonic Day Spa Ltd | Other services | 2009 |
| TOO Funky Productions Limited | Arts & recreation | 2023 |
| Top 8 Limited | Hospitality | 2024 |
| Top Cottage Barmouth Limited | Hospitality | 2024 |
| Top FIX Carpentry Limited | Construction | 2014 |
| Top Hair Cutz Ltd | Other services | 2023 |
| Top Stop Services (Cannock) Ltd | Wholesale & retail | 2015 |
| Tornado Industries Limited | Wholesale & retail | 2012 |
| Torridon Sunrise Management Company Ltd | Real estate | 2019 |
| Tortek Limited | Real estate | 2013 |
| Total Car Repair Center Limited | Wholesale & retail | 2021 |
| Total Construction Supplies (Processing) Limited | Manufacturing | 2021 |
| Total Contracting Solutions UK Limited | Real estate | 2008 |
| Total Electrical & Mechanical Solutions Limited | Administrative & support | 2009 |
| Total Property Management Solutions Limited | Households | 2025 |
| Total Red Interiors Ltd | Construction | 2019 |
| Tower Coffee Limited | Manufacturing | 2024 |
| Tprofile Ltd | Information & communication | 2012 |
| Tprofile Services Ltd | Administrative & support | 2016 |
| TR Wings Limited | Hospitality | 2022 |
| Track "N" Rail Engineering Ltd | Transport & logistics | 2014 |
| Tractor Facilities Ltd | Professional & scientific | 2024 |
| Trade Access Panels Ltd | Wholesale & retail | 2014 |
| Tradeholt Ltd | Wholesale & retail | 2025 |
| Trademarque Tools Limited | Wholesale & retail | 2001 |
| Traden AI Ltd | Information & communication | 2026 |
| Trading, Efficiency & Numerate Solutions Limited | Professional & scientific | 2014 |
| Trafalgar Court Limited | Households | 1991 |
| Traffic Management Personnel Limited | Administrative & support | 2013 |
| Trailhead Gear Services Limited | Administrative & support | 2026 |
| Train Learn Go DW Ltd | Arts & recreation | 2019 |
| Train Learn Go Limited | Administrative & support | 2013 |
| Tranquilla Calm Limited | Health & social care | 2024 |
| Trans Solutions (Midlands & Manchester) Ltd | Transport & logistics | 2009 |
| Trans Solutions Holding Company Limited | Financial services | 2024 |
| Transpart Limited | Professional & scientific | 2014 |
| Transworld Industrial Tools Limited | Wholesale & retail | 2002 |
| Travel With Peta Ltd | Administrative & support | 2025 |
| TRE Engineering Ltd | Construction | 2024 |
| Treatz and Eatz Limited | Manufacturing | 2025 |
| Tree Surgeons Landscaping Limited | Administrative & support | 2023 |
| Tree Tech Arboreal Limited | Administrative & support | 2017 |
| Treeny Limited | Manufacturing | 2003 |
| Trench Lock Autos Ltd | Wholesale & retail | 2026 |
| Trilogy Sports Ltd | Administrative & support | 2025 |
| Triple Point Tutors Limited | Education | 2018 |
| Trow-Poole Consulting Limited | Information & communication | 2006 |
| Troyce Limited | Professional & scientific | 2003 |
| Truck Electrics Ltd | Wholesale & retail | 2026 |
| Truck Tyre Supplies UK Limited | Wholesale & retail | 2017 |
| True Home Investment Limited | Real estate | 2025 |
| Trust Environmental Ltd | Professional & scientific | 2018 |
| TS Granite Limited | Construction | 2015 |
| TSG South Limited | Wholesale & retail | 2016 |
| Tudor Boards Ltd | Manufacturing | 2018 |
| Tudorworth Properties Limited | Construction | 1992 |
| TUF Construct Ltd | Construction | 2024 |
| TUF Impulse Ltd | Transport & logistics | 2019 |
| Tungaloy-Ntk UK Limited | Wholesale & retail | 2010 |
| Turkish RKB Ltd | Other services | 2025 |
| Turn-Ell Limited | Hospitality | 1987 |
| Turner Plastering Limited | Construction | 2007 |
| Turners Trade Paints Ltd | Manufacturing | 2006 |