| TJH ENG Ltd | Professional & scientific | 2020 |
| TKP Consulting Ltd | Professional & scientific | 2018 |
| TL Prop Finco Limited | Administrative & support | 2024 |
| TL Prop Holdco Limited | Administrative & support | 2024 |
| TL PROPCO1 Limited | Administrative & support | 2024 |
| TL PROPCO2 Limited | Administrative & support | 2024 |
| TL PROPCO3 Limited | Administrative & support | 2024 |
| Tllc 2018 Limited | Professional & scientific | 2002 |
| Tllc HOLDINGS2 Limited | Professional & scientific | 2002 |
| TO Focus Limited | Professional & scientific | 2014 |
| Togethermade Ltd | Professional & scientific | 2025 |
| TOM Care Services Limited | Health & social care | 2014 |
| TOM Fordy Ltd | Professional & scientific | 2023 |
| TOM ST. Aubyn Photography Limited | Administrative & support | 2012 |
| TOM Stogdon Limited | Arts & recreation | 2014 |
| TOM Tytherleigh Ltd | Professional & scientific | 2018 |
| Tomorrow Bureau Holdings Ltd | Financial services | 2024 |
| Toppoint U.K. Ltd. | Administrative & support | 1999 |
| Train ME NOW Ltd | Administrative & support | 2015 |
| Trakd Ltd | Information & communication | 2014 |
| Transform Trauma Limited | Health & social care | 2012 |
| Transplant Links | Health & social care | 2007 |
| Travelodge Hotels Isle of MAN Limited | Hospitality | 2026 |
| Travelodge Limited | Extraterritorial | 2010 |
| TRE Bambini Limited | Professional & scientific | 2016 |
| Treatex Limited | Wholesale & retail | 2002 |
| Treckky Ltd | Administrative & support | 2025 |
| Trendlytics Ltd | Information & communication | 2024 |
| Trialgrid Limited | Administrative & support | 2016 |
| Trialmedica Limited | Professional & scientific | 2008 |
| Tricorder Care Services Limited | Transport & logistics | 2007 |
| Tring Road Property Management Limited | Real estate | 2010 |
| Trinity Land (Headington) Limited | Real estate | 2018 |
| Trinity Oxford Properties Limited | Real estate | 2014 |
| Trinity Residential Land Limited | Real estate | 2009 |
| Triplex Property Group Limited | Construction | 2024 |
| Trkgss Properties Ltd | Real estate | 2022 |
| Tro-Tro Medical Ltd | Health & social care | 2019 |
| Trowel Holding Limited | Financial services | 2023 |
| Tsbm Ltd | Hospitality | 2014 |
| TSS Holdings Limited | Financial services | 2022 |
| TT Recycling Solutions Ltd | Water & waste | 2009 |
| Ttandem Consulting LLP | | 2016 |
| TTP Foods Ltd | Financial services | 2020 |
| TTP Snacks Limited | Manufacturing | 2012 |
| Tudor Maynard Limited | Other services | 2026 |
| Tulu Ltd | Administrative & support | 2014 |
| Tutease Limited | Information & communication | 2024 |
| TW Jones Holdings Ltd | Financial services | 2026 |
| TW Jones Property Developments Ltd | Construction | 2026 |
| TW Jones Property Ltd | Construction | 2017 |
| Tyger Valley Systems Limited | Information & communication | 2008 |
| Ultimate Finish (Oxford) Limited | Wholesale & retail | 2006 |
| Ultrablanket Ltd | Manufacturing | 2024 |
| Ultrasound Scanners Limited | Professional & scientific | 2009 |
| Uncanny Studio LLP | | 2024 |
| Unit Hair Ltd | Other services | 2019 |
| United Legal Services Limited | Information & communication | 2002 |
| UP That Ladder Limited | Real estate | 2025 |
| UP Training & Development Limited | Administrative & support | 2004 |
| Urban DNA Solutions LLP | | 2014 |
| Uxed Ltd | Professional & scientific | 2023 |
| V2O Group Ltd | Wholesale & retail | 2021 |
| Vancheeswaran Health Ltd | Health & social care | 2016 |
| Vanguard Management Systems Ltd | Professional & scientific | 2015 |
| VANS2YOU Limited | Transport & logistics | 2025 |
| VCT Holdings Limited | Professional & scientific | 2015 |
| VDM Management Ltd | Arts & recreation | 2013 |
| Veganbunny Ltd | Manufacturing | 2015 |
| Venerable Consulting Limited | Professional & scientific | 2015 |
| Vertec Limited | Construction | 2012 |
| Very Very FAR Away Limited | Arts & recreation | 2022 |
| VIC Films Limited | Information & communication | 1961 |
| Viewpoint Videos Ltd | Information & communication | 2013 |
| Vincent Chatel Designs Limited | Information & communication | 2014 |
| Vincent-Hale Services Limited | Administrative & support | 2022 |
| Virgo Trading Ltd | Hospitality | 2022 |
| Visit Oxfordshire Limited | Administrative & support | 2011 |
| Vivanova Inc Ltd | Administrative & support | 2026 |
| Vjen Consulting Ltd | Administrative & support | 2020 |
| VKS Capital Ltd | Financial services | 2025 |
| VON Delft Preclinical Consulting Ltd | Health & social care | 2023 |
| Vorticity Limited | Professional & scientific | 2001 |
| W and T Property Portfolio Ltd | Real estate | 2009 |
| W&T TP LLP | | 2023 |
| W. & G.Properties Limited | Real estate | 1963 |
| W.Bignall & Company Limited | Real estate | 1920 |
| Walford Company Limited | Financial services | 2019 |
| Warp Critical Limited | Information & communication | 2000 |
| Watch Doctors Limited | Other services | 2026 |
| Water 365 Limited | Professional & scientific | 2023 |
| Waterlands Farm Limited | Agriculture & fishing | 2009 |
| Watermead Financial Solutions Limited | Financial services | 2010 |
| Watlington Hospital Charitable Trust | Health & social care | 2000 |
| Waygold Limited | Manufacturing | 1984 |
| Wayzgoose Limited | Manufacturing | 2020 |
| WE Made That LLP | | 2011 |
| WE Made That Studio Ltd | Professional & scientific | 2014 |
| Weaver Investment Properties Ltd | Real estate | 2024 |
| Weber Food Technology Limited | Wholesale & retail | 2023 |