| Telensa Holdings Limited | Information & communication | 2015 |
| Telensa Ltd | Information & communication | 2002 |
| Telescan Security Systems Limited | Wholesale & retail | 1984 |
| Television Lifts Limited | Wholesale & retail | 2008 |
| Telfer Partners Limited | Administrative & support | 2014 |
| Telfmy Limited | Education | 2017 |
| Temikra Ltd | Manufacturing | 2020 |
| Temotuf Industrial Solutions Ltd. | Manufacturing | 2024 |
| Templars Court (Royston) Management Company Limited | Real estate | 2002 |
| Temple Grove Management Company Limited | Households | 2003 |
| Temple Life Holding Ltd | Manufacturing | 2026 |
| Tempscb Ltd | Wholesale & retail | 2025 |
| TEN to the Nine Limited | Professional & scientific | 2025 |
| TEN Tonne Truck Holdings Limited | Financial services | 2023 |
| Tenamore Ltd | Wholesale & retail | 2012 |
| Tene Solutions Ltd | Manufacturing | 2026 |
| Tenghe Media Ltd | Wholesale & retail | 2025 |
| Tenison Life Sciences Ltd | Professional & scientific | 2025 |
| Tenison Taxis Ltd | Transport & logistics | 2022 |
| Tennis Shorts Ltd | Education | 2024 |
| Tenoke Limited | Health & social care | 2015 |
| Tenset Technologies Limited | Information & communication | 1989 |
| Tensorlink Technologies Limited | Wholesale & retail | 2024 |
| Tenterfell Ltd | Information & communication | 2025 |
| Tentsmuir Limited | Professional & scientific | 2017 |
| Tenyks Limited | Information & communication | 2019 |
| Tephra Digital Limited | Professional & scientific | 2026 |
| Terah IT Ltd | Information & communication | 2013 |
| Teraprobe Limited | Manufacturing | 2000 |
| Teraview Holdings PLC | Manufacturing | 2024 |
| Teraview Limited | Manufacturing | 2000 |
| Tereyn Architects Limited | Professional & scientific | 2020 |
| Tereyn Limited | Construction | 2020 |
| Terra Solve Ltd | Professional & scientific | 2008 |
| Terrafuture Ltd | Professional & scientific | 2026 |
| Terrain Systems Ltd | Information & communication | 2026 |
| Terry Gregory Limited | Manufacturing | 2015 |
| Terry's Electrical Services Ltd. | Construction | 2003 |
| Tertium AI Limited | Professional & scientific | 2026 |
| Tery Consulting Ltd | Professional & scientific | 2020 |
| Tesseract LAB Limited | Manufacturing | 2024 |
| Testing for ALL Ltd | Health & social care | 2020 |
| Tesu Health Ltd | Information & communication | 2023 |
| Tethercells Limited | Information & communication | 2021 |
| TEV AHO Ltd | Health & social care | 2010 |
| Teversham Motors Ltd | Wholesale & retail | 2013 |
| Tewgas Limited | Health & social care | 2019 |
| Tewich Limited | Professional & scientific | 2021 |
| Texmed International Ltd | Wholesale & retail | 2025 |
| Texus Ltd | Wholesale & retail | 2024 |
| Teztrading Ltd | Financial services | 2026 |
| TF Property Solutions Ltd | Real estate | 2016 |
| TF Takeaway Ltd | Hospitality | 2021 |
| Tfrod Trade Ltd | Wholesale & retail | 2025 |
| Tfwx Limited | Information & communication | 2015 |
| TG NRG Limited | Information & communication | 2020 |
| TH3RDCURVE Global Ltd | Financial services | 2023 |
| TH3RDCURVE Limited | Professional & scientific | 2016 |
| Thackray Properties Limited | Real estate | 1971 |
| Thagus Ltd. | Professional & scientific | 2015 |
| Thalia Shaw Ltd | Real estate | 2023 |
| Thames International Shipping Limited | Wholesale & retail | 2025 |
| Thand Ltd | Information & communication | 2026 |
| Thanh Binh Limited | Hospitality | 2015 |
| Tharan Services Ltd | Real estate | 2024 |
| Tharros Limited | Agriculture & fishing | 1993 |
| That Design Co Limited | Construction | 2016 |
| That Wave Entertainment Ltd | Information & communication | 2026 |
| Thaumagen Limited | Information & communication | 2005 |
| THC Business Connect Ltd | Administrative & support | 2023 |
| THE 3D Printer People Ltd | Information & communication | 2014 |
| THE A11 Group Ltd | Wholesale & retail | 2007 |
| THE Academy of Ancient Music | Education | 2000 |
| THE Academy of Urbanism (Number 2) Limited | Education | 2006 |
| THE Academy of Urbanism Limited | Education | 2005 |
| THE Acteon Consultancy LLP | | 2001 |
| THE Aemp Estate Management Company Limited | Real estate | 2023 |
| THE African Conservation and Development Foundation | Agriculture & fishing | 2007 |
| THE Akenham Partnership Limited | Professional & scientific | 2003 |
| THE Alarm Hub Ltd | Professional & scientific | 2017 |
| THE Alkaptonuria Society Ltd | Health & social care | 2003 |
| THE Anchor and Water Ltd | Information & communication | 2025 |
| THE Ancient Shepherds Ltd | Hospitality | 2017 |
| THE Andrew Johnson Rowing Foundation | Arts & recreation | 2021 |
| THE Animal Sense Company Ltd | Manufacturing | 2026 |
| THE Applied Knowledge Network Limited | Information & communication | 2010 |
| THE Arable Group Limited | Agriculture & fishing | 1923 |
| THE Arbory Trust | Other services | 1999 |
| THE ARC (Cherry Hinton) Limited | Real estate | 2009 |
| THE Architect Studio Ltd | Professional & scientific | 2021 |
| THE Art Assembly Ltd | Extraterritorial | 2022 |
| THE Arts Theatre Cambridge | Arts & recreation | 2024 |
| THE Ashes Management Company Limited | Households | 1994 |
| THE Aspect Creative Ltd | Professional & scientific | 2023 |
| THE Association of Research Managers and Administrators (UK) | Other services | 2006 |
| THE Atrium RTM Company Limited | Households | 2011 |
| THE Aurelie House Ltd | Wholesale & retail | 2025 |
| THE AZ Alim Group Ltd | Construction | 2023 |
| THE B17 Steam Locomotive Trust | Manufacturing | 2011 |
| THE Babraham Institute | Professional & scientific | 1995 |