| THE L&E Dining Ltd | Hospitality | 2025 |
| THE Laughing Story Ltd | Information & communication | 2022 |
| THE Life Space Project CIC | Education | 2024 |
| THE Locksley Group Ltd | Construction | 2016 |
| THE Loose Cannon Brewing Company Limited | Manufacturing | 2007 |
| THE M.S. Therapy Centre (Oxford) Ltd. | Health & social care | 1988 |
| THE Magdalen Estate Limited | Construction | 2014 |
| THE Manor Preparatory School Trust | Education | 1989 |
| THE Metagenomic Testing Company Ltd | Professional & scientific | 2025 |
| THE Microfactory Limited | Manufacturing | 2015 |
| THE Military Gallery Limited | Professional & scientific | 1980 |
| THE Motherinlawns Ltd | Construction | 2024 |
| THE New Fish Company Limited | Hospitality | 2007 |
| THE New Lawn Company Oxford Limited | Wholesale & retail | 2009 |
| THE Next Apple Limited | Administrative & support | 2025 |
| THE O Clinic London Limited | Health & social care | 2019 |
| THE Old Gaol (Abingdon) Management Company NO 1 Limited | Households | 2011 |
| THE Old Gaol (Abingdon) Management Company NO 2 Limited | Households | 2011 |
| THE Old Shed (Charlbury) Limited | Hospitality | 2016 |
| THE Old Shed Events Limited | Other services | 2021 |
| THE Online Stove Shop Limited | Wholesale & retail | 2014 |
| THE Otmoor Lodge Limited | Hospitality | 2004 |
| THE Oxbridge Method Limited | Other services | 2025 |
| THE Oxford Engraver Limited | Administrative & support | 2009 |
| THE Oxford Mechanical & Electrical Company Ltd | Construction | 2014 |
| THE Oxford Mechanical Company Ltd | Extraterritorial | 2021 |
| THE Oxford Scone Company Limited | Manufacturing | 2025 |
| THE Oxford Snob Ltd | Other services | 2015 |
| THE Oxfordshire Building Company Limited | Construction | 2021 |
| THE Performance Vault Ltd | Arts & recreation | 2025 |
| THE Play Park Eastleigh Ltd | Arts & recreation | 2026 |
| THE Play Park Romsey Ltd | Arts & recreation | 2025 |
| THE Purple Group Limited | Professional & scientific | 1997 |
| THE Redeemed Christian Church of GOD Salvation House Didcot | Other services | 2024 |
| THE Retreat Abingdon Limited | Other services | 2012 |
| THE Rude MUG Company Ltd | Wholesale & retail | 2025 |
| THE Slip Slope Ltd | Other services | 2020 |
| THE Smart Villages Foundation Ltd | Professional & scientific | 2011 |
| THE Southey Way Ltd | Arts & recreation | 2016 |
| THE ST Lawrence Besselsleigh Trust | Arts & recreation | 2014 |
| THE Thicket Freehold Limited | Households | 2015 |
| THE Unicorn Trust | Education | 1998 |
| THE Van MAN Supreme Limited | Transport & logistics | 2025 |
| THE Virtual Catalogue Company Limited | Manufacturing | 2013 |
| THE Wedding Sanctuary Limited | Professional & scientific | 2011 |
| THE Welkin Group Limited | Construction | 2022 |
| Theoxfordmassageacademy Ltd | Education | 2024 |
| Therapy XYZ Ltd | Arts & recreation | 2021 |
| Thermal Lining Ltd | Construction | 2024 |
| Thesium Limited | Information & communication | 2023 |
| Thetravelgateway Ltd | Administrative & support | 2016 |
| Think Exec Limited | Professional & scientific | 2026 |
| Thirtyfivebio Limited | Professional & scientific | 2021 |
| This Inner Voice Music Therapy Ltd | Other services | 2025 |
| Thistle and Rose Events Ltd | Administrative & support | 2024 |
| Thomas Leach Limited | Manufacturing | 1925 |
| Thomas Merrifield Commercial Limited | Professional & scientific | 2007 |
| Thompson & Terry Ltd | Administrative & support | 2014 |
| Thomtech Holdings Ltd | Financial services | 2025 |
| Three Peaks Associates Ltd. | Professional & scientific | 2003 |
| Three River Fiction Limited | Information & communication | 2014 |
| Three River Studios Limited | Information & communication | 2013 |
| Thruvision Group PLC | Information & communication | 2010 |
| Thruvision Limited | Information & communication | 2017 |
| TI VAS Car Sales Ltd | Wholesale & retail | 2019 |
| Tight Circle Limited | Arts & recreation | 2018 |
| Tile-Line Ltd | Construction | 2021 |
| TIM Rayne Consulting Limited | Information & communication | 2005 |
| Time 2 Bounce Ltd | Arts & recreation | 2013 |
| Timsbury Court Management Company Limited | Households | 2004 |
| Tink Thank Productions Limited | Information & communication | 1989 |
| Tiny Adventure Oxford Ltd | Professional & scientific | 2023 |
| TJG Creative Ltd | Information & communication | 2015 |
| TK Cultural Limited | Real estate | 2019 |
| TK Marketing & Strategy Consulting Ltd | Professional & scientific | 2011 |
| TL Jewellers Limited | Wholesale & retail | 2003 |
| TM Bridge Ltd | Transport & logistics | 2023 |
| TMH Trading Limited | Manufacturing | 2018 |
| TO the Death LLP | | 2020 |
| Toddler Town Montessori Ltd | Education | 2020 |
| Tokamak Energy Ltd | Professional & scientific | 2009 |
| Tokamak Solutions EBT Limited | Professional & scientific | 2013 |
| TOM Marquand Ltd | Arts & recreation | 2017 |
| Tomahawk Tech UK Limited | Professional & scientific | 2017 |
| Tonks Brothers Funeral Directors Limited | Other services | 2013 |
| Tonytaxi Ltd | Transport & logistics | 2019 |
| Top Speed Tuning Ltd | Wholesale & retail | 2019 |
| TOR Cottage Rentals Limited | Real estate | 2020 |
| Torpenhow Hill Ltd | Professional & scientific | 2024 |
| Tortoise & Hare Limited | Wholesale & retail | 2022 |
| Total Electrical Contractors Limited | Manufacturing | 2016 |
| Total Group Capital Ltd | Financial services | 2024 |
| Total Projects (UK) Limited | Manufacturing | 2011 |
| Tour Ntwk Limited | Arts & recreation | 2024 |
| Tourmouse Productions Limited | Arts & recreation | 2022 |
| TP Property Holdings Ltd | Real estate | 2018 |
| Tpmj Enterprises Ltd | Wholesale & retail | 2023 |
| Trade Magic Projects LLP | | 2014 |
| Tradevisionsoftware Ltd | Information & communication | 2025 |
| Trail Tuff Ltd | Wholesale & retail | 2025 |