| TMP Chiro Limited | Health & social care | 2020 |
| TMW Recruitment Ltd | Administrative & support | 2025 |
| TN Sports Medicine Limited | Health & social care | 2023 |
| TNB Properties Ltd | Real estate | 2025 |
| TNP Inn Limited | Hospitality | 2018 |
| Tobias Bar Limited | Administrative & support | 2016 |
| Tobias Oakwood Limited | Hospitality | 2018 |
| Toddington Lettings Limited | Real estate | 2025 |
| Toddington Properties Ltd | Real estate | 2024 |
| Toddington Sourcing Limited | Administrative & support | 2025 |
| Together Commercial Limited | Construction | 2019 |
| Together Housing Finance PLC | Financial services | 2012 |
| Together Roof Energy Limited | Professional & scientific | 2011 |
| Together Roof Energy SPV Limited | Construction | 2011 |
| Toheda Ltd | Real estate | 2014 |
| Tollplas Limited | Manufacturing | 2021 |
| TOM Goddard and Sons Limited | Agriculture & fishing | 2000 |
| TOM Miskell Limited | Other services | 2014 |
| Tomasz Pawelka Ltd | Construction | 2020 |
| Tommy Tang Ltd | Health & social care | 2013 |
| Tompol - Transport Ltd | Transport & logistics | 2015 |
| Tony Tilers Limited | Construction | 2018 |
| Toot Hill Pet Boarding Limited | Hospitality | 2021 |
| Tooth Fruitz Limited | Wholesale & retail | 2022 |
| Top Club 68 Entertainment Ltd | Arts & recreation | 2022 |
| Top Dental (Products) Limited | Manufacturing | 2001 |
| Top Farm Catering Ltd | Hospitality | 2020 |
| Top Fisheries Ltd | Hospitality | 2024 |
| Top Notch North West Limited | Construction | 2014 |
| Top Notch Properties (Yorkshire) Limited | Real estate | 2025 |
| Top Sheet Cladding Limited | Construction | 2020 |
| Topaz Twenty Nine Limited | Other services | 2019 |
| Topcoat Bodyshop Ltd | Wholesale & retail | 2025 |
| Topcoat Holdings Ltd | Wholesale & retail | 2025 |
| Topderm Limited | Health & social care | 2024 |
| Topliss Holdings Limited | Professional & scientific | 2016 |
| Topmoor Shepp Ltd | Wholesale & retail | 2024 |
| Topo Restaurant Ltd | Hospitality | 2025 |
| Toposs Ltd | Hospitality | 2018 |
| Toppers Deli Ltd | Hospitality | 2013 |
| Toptrade Improvements Ltd | Construction | 2025 |
| TOR Properties Limited | Real estate | 2006 |
| Torevell Dent (Audit) LLP | | 2002 |
| Torevell Dent (Holdings) Limited | Professional & scientific | 2006 |
| Torevell Dent LLP | | 2002 |
| Tori Lynn Crowther Limited | Administrative & support | 2018 |
| Tornhill West Ltd | Wholesale & retail | 2024 |
| Toro Verde GT Limited | Arts & recreation | 2018 |
| Torora AI LLP | | 2025 |
| Torque Commerce Limited | Professional & scientific | 2026 |
| Torque Motor Group Ltd | Wholesale & retail | 2024 |
| Torque Rush Autos (TRA) Ltd | Wholesale & retail | 2025 |
| Torque Tech Automotive Ltd | Wholesale & retail | 2025 |
| TOT Spot Day Nursery Limited | Administrative & support | 2002 |
| Total Active Limited | Wholesale & retail | 2017 |
| Total Appliance Care Ltd | Professional & scientific | 2021 |
| Total Care Chiropody & Podiatry Clinic (Bristol) Ltd | Health & social care | 2026 |
| Total Care Chiropody & Podiatry Holdings Ltd | Health & social care | 2026 |
| Total Meat Supplies Limited | Wholesale & retail | 2005 |
| Total Tour Solutions Limited | Extraterritorial | 2012 |
| Total Tour Support Ltd | Extraterritorial | 2011 |
| Totally Attractions Ltd | Arts & recreation | 2020 |
| Totally Bonkers Ltd | Information & communication | 2018 |
| Totally Locally Ltd | Professional & scientific | 2010 |
| Totally Locally Towns CIC | Professional & scientific | 2025 |
| Totally-Bridal (UK) Ltd | Wholesale & retail | 2014 |
| Totem C&C Ltd | Hospitality | 2022 |
| Touchpointco. Ltd | Wholesale & retail | 2023 |
| Toulston Polo Club Ltd | Extraterritorial | 2021 |
| Tourbloke Limited | Professional & scientific | 2010 |
| Tower Building Properties Limited | Construction | 2021 |
| Tower Competitions Ltd | Arts & recreation | 2025 |
| Tower Hill Practice Ltd | Administrative & support | 2017 |
| Towerhill Healthcare Practice Ltd | Health & social care | 2023 |
| Town and Country Construction WY Limited | Administrative & support | 2022 |
| Town Bars Ltd | Hospitality | 2024 |
| Town ING Mills (Block a) Management Company Limited | Real estate | 2007 |
| Town ING Mills (Block B) Management Company Limited | Households | 2005 |
| Townberry Interiors Ltd | Construction | 2021 |
| Towngate Associates Ltd | Professional & scientific | 2006 |
| TP Suits Ltd | Wholesale & retail | 2014 |
| Tpca Ducie Limited | Real estate | 2026 |
| Tpca Ducie OP Limited | Real estate | 2026 |
| TPM Accountancy Services Ltd | Information & communication | 2016 |
| TR Cars Ltd | Professional & scientific | 2015 |
| Tracey Elliott Independent Mortgage Adviser Ltd | Financial services | 2025 |
| Tracker Guard UK Ltd | Administrative & support | 2023 |
| Tradcon Homes Limited | Construction | 2018 |
| Trade Forward Electrical Wholesalers Limited | Wholesale & retail | 1983 |
| Trade Tiling Limited | Wholesale & retail | 2017 |
| Trade Winds Community Limited | Other services | 2025 |
| Trademax International Ltd | Wholesale & retail | 2024 |
| Tradesub Ltd | Information & communication | 2026 |
| Trading Stoic UK Ltd | Information & communication | 2024 |
| Trafalgar Inn Limited | Hospitality | 2002 |
| Trans-Courier Ltd | Transport & logistics | 2019 |
| Transition 360 Limited | Other services | 2015 |
| Translate UK Limited | Professional & scientific | 2006 |
| Transmek Ltd | Transport & logistics | 2019 |
| Transylvania Wine Ltd | Wholesale & retail | 2015 |