| TC Central Limited | Other services | 2018 |
| TC Wickham Ltd | Other services | 2019 |
| TCB Weavers Ltd | Other services | 2024 |
| Tcbrian Property Ltd | Real estate | 2017 |
| TCG Dragon Limited | Wholesale & retail | 2024 |
| Tcgjohny Ltd | Wholesale & retail | 2025 |
| Tcgrader Ltd | Information & communication | 2025 |
| Tciu Solutions Limited | Professional & scientific | 2017 |
| TCM Link Ltd | Public administration | 2023 |
| TCM Reach Ltd | Professional & scientific | 2024 |
| TCN Group Limited | Wholesale & retail | 2015 |
| TCR Specsavers Hearcare Limited | Wholesale & retail | 2021 |
| TCR Specsavers Limited | Wholesale & retail | 1999 |
| TCR Visionplus Limited | Wholesale & retail | 1999 |
| TCS Technical Ltd | Manufacturing | 2022 |
| TCW Install Ltd | Construction | 2021 |
| TCW Removals Limited | Transport & logistics | 2022 |
| TD Services Limited | Health & social care | 2023 |
| Teach Globally Limited | Education | 2024 |
| Teaching to Mastery (Deep Learning T2M) Ltd | Education | 2022 |
| TEC Services (Southern) Ltd | Construction | 2003 |
| Tech & Trends Ltd | Wholesale & retail | 2024 |
| Tech Event Services Limited | Arts & recreation | 2014 |
| Tech Whizz Solutions Ltd | Information & communication | 2026 |
| Tech Work Solutions Ltd | Information & communication | 2024 |
| Tech-Met Ltd | Manufacturing | 2015 |
| Techbox Events Ltd | Arts & recreation | 2018 |
| Techdotpeople Limited | Information & communication | 2019 |
| Techelek Ltd | Construction | 2018 |
| Techneek Limited | Information & communication | 2025 |
| Technical Wizardry Ltd | Professional & scientific | 2016 |
| Techniche Global Limited | Administrative & support | 2015 |
| Technomax Marine Ltd | Information & communication | 2020 |
| Technoplex Holdings Limited | Financial services | 2026 |
| TECHS4EDUCATION Limited | Information & communication | 2009 |
| Techvantage Limited | Information & communication | 2023 |
| Tecnoseal UK Limited | Wholesale & retail | 2012 |
| Tecstra Advisory Ltd | Professional & scientific | 2025 |
| TED Cabling Comms Ltd | Information & communication | 2021 |
| Tedfm Ltd | Information & communication | 2024 |
| Teesmedals Ltd | Wholesale & retail | 2026 |
| Teesside Domi Audiology Specsavers Limited | Wholesale & retail | 2024 |
| Teesside Newmedica Limited | Health & social care | 2018 |
| TEH 29 Ltd | Administrative & support | 2013 |
| Teignmouth Specsavers Limited | Wholesale & retail | 2007 |
| Teignmouth Visionplus Limited | Wholesale & retail | 2007 |
| Telemetry Engineering Solutions Limited | Professional & scientific | 2023 |
| Telford Specsavers Hearcare Limited | Wholesale & retail | 2019 |
| Tellymix Ltd | Information & communication | 2018 |
| Telmar Ltd | Real estate | 2018 |
| Telos Therapies Ltd | Health & social care | 2020 |
| Tempa Watches Limited | Wholesale & retail | 2025 |
| Temple Bar Management Limited | Real estate | 2007 |
| Temple Paraplanning Limited | Financial services | 2016 |
| Temple Wealth Management Ltd | Financial services | 2010 |
| TEN Cubed Property Ltd | Real estate | 2024 |
| TEN TON Cat Ltd | Information & communication | 2014 |
| Tender Path Support Ltd | Health & social care | 2025 |
| Tennyson Insurance Limited | Financial services | 1995 |
| Teno Media Limited | Professional & scientific | 2021 |
| Tenterden Specsavers Limited | Wholesale & retail | 2018 |
| Tenth Harmony Ltd | Real estate | 2023 |
| Tenth MAN I-Design Limited | Professional & scientific | 2023 |
| Terra Firma Stevedores Ltd | Wholesale & retail | 2024 |
| Terraform Research Limited | Manufacturing | 2022 |
| Tesla Electrical Ltd | Construction | 2017 |
| Tessaa Limited | Health & social care | 2023 |
| Tessarawrx Ltd | Financial services | 2026 |
| Tessarawrxmedia Ltd | Information & communication | 2026 |
| Tesserawrxbuild Ltd | Real estate | 2026 |
| Tetbury Specsavers Limited | Wholesale & retail | 2023 |
| Tetra Developments Limited | Real estate | 2025 |
| Teves Group Ltd | Real estate | 2026 |
| Tewkesbury Specsavers Limited | Wholesale & retail | 2002 |
| Text - Date Limited | Wholesale & retail | 2002 |
| TFS Associates Limited | Professional & scientific | 2017 |
| TG Landscapes Ltd | Administrative & support | 2024 |
| Tglk Enterprise Ltd | Other services | 2023 |
| TH Composites Ltd | Manufacturing | 2024 |
| Thai Experience Massage and Spa Ltd | Health & social care | 2020 |
| Thame Specsavers Limited | Wholesale & retail | 2018 |
| That Film Editor Limited | Information & communication | 2012 |
| Thatchers (Motors UK) Ltd | Wholesale & retail | 2020 |
| Thbp Ltd | Construction | 2023 |
| THE Affable Partnership Ltd | Administrative & support | 2025 |
| THE Airline Group Limited | Professional & scientific | 2000 |
| THE Alarm People Ltd | Administrative & support | 2012 |
| THE Alarming Company Limited | Other services | 1991 |
| THE Alexandra Beer Emporium Ltd | Hospitality | 2018 |
| THE Almost Future Limited | Information & communication | 2025 |
| THE Andover BIN Wizards Ltd | Administrative & support | 2025 |
| THE Antennae Collective Limited | Professional & scientific | 2017 |
| THE Artful Baker Ltd | Manufacturing | 2013 |
| THE Artist Galleries Limited | Wholesale & retail | 2008 |
| THE Association for Geographic Information | Other services | 1989 |
| THE Association for Palliative Medicine of Great Britain and Ireland | Other services | 1996 |
| THE Atmos Company Limited | Professional & scientific | 2022 |
| THE Aurox Meat Company Ltd | Manufacturing | 2023 |
| THE Bakehouse @ Denmead Limited | Wholesale & retail | 2014 |
| THE Balearic Group Limited | Hospitality | 2024 |