| Table Place Chairs Limited | Manufacturing | 2012 |
| TAH Services Ltd | Real estate | 2025 |
| Tail Distribution Ltd | Wholesale & retail | 2015 |
| Tail Holdings Limited | Information & communication | 2018 |
| Tail Software Limited | Information & communication | 2018 |
| Taillefer Mechanical Engineering Ltd | Professional & scientific | 2022 |
| Tails and Tweed Pet Grooming Ltd | Other services | 2024 |
| Tait Miller Ltd | Information & communication | 2025 |
| Taiwilfashion Ltd | Wholesale & retail | 2022 |
| TAL Management Limited | Information & communication | 2023 |
| Talbot Ltd | Construction | 2024 |
| Tales of 51 Zero Limited | Professional & scientific | 2018 |
| Tame Your Day Limited | Wholesale & retail | 2025 |
| TAN TAN Courier Services Limited | Transport & logistics | 2022 |
| Tania Cleaning 2019 Limited | Administrative & support | 2019 |
| Tarncourt Developments Limited | Real estate | 2023 |
| Tasty Treats Cafe Ltd | Hospitality | 2025 |
| Tax File NOW Ltd | Professional & scientific | 2017 |
| Tayken Over Ltd | Information & communication | 2023 |
| Taylor-Made Mobility Limited | Construction | 2021 |
| Taylored Electrical Services Limited | Construction | 2025 |
| Taylorollinson Limited | Administrative & support | 2013 |
| Tazim Ltd | Hospitality | 2016 |
| TBC Apparel Ltd | Wholesale & retail | 2026 |
| TC Construction Oxford Ltd | Construction | 2022 |
| TCF Electrical Services Ltd | Construction | 2013 |
| TCI Renewables Limited | Construction | 2005 |
| TCO Touring Ltd | Arts & recreation | 2015 |
| Technical Aviation Publications Limited | Information & communication | 1991 |
| Technology Research Limited | Professional & scientific | 1992 |
| Telegraphy Ltd | Professional & scientific | 2020 |
| Television Audio Ltd | Information & communication | 2014 |
| Telpip Consulting Limited | Information & communication | 2019 |
| Tempo Sound Limited | Other services | 2015 |
| Terrestrial Energy Limited | Energy | 2016 |
| Tetra Tech Consulting Limited | Professional & scientific | 1979 |
| Tetra Tech Environmental Management Limited | Professional & scientific | 1983 |
| Tetra Tech Europe Executive Services Limited | Professional & scientific | 2017 |
| Tetra Tech Occupational Health Limited | Health & social care | 1999 |
| Tetra Tech RPS Energy Consultants Limited | Administrative & support | 1996 |
| Tetra Tech RPS Energy Limited | Mining & quarrying | 1979 |
| Tetra Tech UK Holdings Limited | Professional & scientific | 2006 |
| Tetra Tech UK Limited | Professional & scientific | 2019 |
| Tfbio Limited | Professional & scientific | 2022 |
| Tgmac Ltd | Construction | 2012 |
| Thallo Properties Limited | Real estate | 2026 |
| Thame LEA Park Management Company (2) Limited | Extraterritorial | 1978 |
| Thames Carpentry and Construction Limited | Construction | 2013 |
| Thames Neuropsychology Ltd | Health & social care | 2024 |
| Thames Valley Classics Limited | Other services | 2016 |
| Thames Valley Copiers Limited | Administrative & support | 2016 |
| Thames Valley Excavators Limited | Administrative & support | 1989 |
| Thames Valley Maintenance (Oxford) Limited | Construction | 2003 |
| Thames Valley Roofing & Painting Limited | Construction | 2021 |
| Thameside Clinical Ltd | Professional & scientific | 2024 |
| That Proptech GUY Ltd | Information & communication | 2024 |
| Thaxter Holdings Limited | Financial services | 2019 |
| THE A7 Group Ltd | Administrative & support | 2016 |
| THE Abbey Sutton Courtenay Limited | Other services | 1979 |
| THE Abbey Tasc Limited | Hospitality | 2025 |
| THE Abingdon Honey Co Limited | Extraterritorial | 2015 |
| THE Abingdon Open Door Project. | Health & social care | 2003 |
| THE Abingdon Window Company Ltd | Construction | 2006 |
| THE Appleton Project CIC | Education | 2026 |
| THE Arthur Anson Memorial Trust Limited | Administrative & support | 2004 |
| THE Association of Industrial Laser Users | Other services | 1995 |
| THE Association of Relocation Professionals | Other services | 1986 |
| THE Barns Cafe Limited | Hospitality | 2013 |
| THE Beaming Smile Company Limited | Real estate | 2001 |
| THE Benson Bulletin News CIC | Information & communication | 2020 |
| THE Brushworks Limited | Arts & recreation | 2024 |
| THE Built Heritage Consultancy Limited | Professional & scientific | 2010 |
| THE Charterhouse Oxford Consultancy Limited | Information & communication | 2016 |
| THE Church in Abingdon Development Trust Ltd. | Other services | 1980 |
| THE Clean Wizards Ltd | Administrative & support | 2018 |
| THE Coal Office Ltd | Real estate | 2023 |
| THE Coding Guild Ltd | Education | 2019 |
| THE College of Health Ltd | Education | 2017 |
| THE Conifer Drive Management Company Limited | Households | 1997 |
| THE Corporate Hamper Company Limited | Wholesale & retail | 2004 |
| THE Crossroad Grocery Ltd | Wholesale & retail | 2024 |
| THE Dairy Meadow Residents Management Company Limited | Households | 1993 |
| THE Dale Headington Limited | Households | 2001 |
| THE Dial House Partnership Limited | Information & communication | 2005 |
| THE Downbeat Ltd | Wholesale & retail | 2021 |
| THE Dream Writers Ltd | Professional & scientific | 2021 |
| THE Driveway & Patio Company Limited | Construction | 2013 |
| THE European Institute of Golf Course Architects | Other services | 1998 |
| THE Experience Specialists Group Ltd | Financial services | 2017 |
| THE Finishing Touch (2003) Ltd | Wholesale & retail | 2003 |
| THE Funky Teapot Limited | Arts & recreation | 2005 |
| THE Gathering Space Ltd | Wholesale & retail | 2025 |
| THE Genius Group Solutions Limited | Information & communication | 2015 |
| THE Gentleman Cowboy Ltd | Wholesale & retail | 2025 |
| THE Gibson Partnership Ltd | Real estate | 2022 |
| THE Inked Octopus Ltd | Arts & recreation | 2025 |
| THE International College at Robert Gordon University Ltd | Education | 2010 |
| THE IVY Agency Limited | Professional & scientific | 2020 |
| THE Jammer Bars Limited | Hospitality | 2021 |
| THE Kash Crown Ltd | Wholesale & retail | 2025 |