| Train to Care Oxfordshire Ltd | Health & social care | 2025 |
| Transatlantic Artists.Com Limited | Administrative & support | 2018 |
| Transcamion Limited | Administrative & support | 2014 |
| Transcendence Concerts Limited | Arts & recreation | 2018 |
| Transport Management Solutions Ltd | Information & communication | 2004 |
| Treknow Property Services Ltd | Real estate | 2016 |
| Trenchwood Limited | Construction | 2006 |
| Treq Global Ltd | Manufacturing | 2024 |
| Treruffe Place Management Company Limited | Households | 2007 |
| Tresefir Limited | Real estate | 1978 |
| Trevillion Architects Limited | Professional & scientific | 2021 |
| Trevor Whelan Racing Limited | Arts & recreation | 2024 |
| TRI Training Harder LLP | | 2010 |
| Triarii Communications Limited | Information & communication | 2008 |
| Tricam Construction Ltd. | Construction | 2008 |
| Trifu Building Limited | Construction | 2024 |
| Trinito Digital Limited | Information & communication | 2022 |
| Trinity Capital (Limpley) Limited | Construction | 2021 |
| Tristan Durrell Racing Ltd | Arts & recreation | 2026 |
| TRS Cooling Limited | Construction | 2015 |
| TRS Energy Limited | Construction | 2024 |
| Truckandman Ltd | Transport & logistics | 2024 |
| True Flourish Ltd | Households | 2020 |
| True-Light Productions Limited | Administrative & support | 2012 |
| Trustontap Ltd | Health & social care | 2015 |
| Trustontap Trading Ltd | Administrative & support | 2026 |
| Truvay Prestigeserve Ltd | Wholesale & retail | 2025 |
| TSC Lifesciences Limited | Professional & scientific | 2023 |
| TSK Recruitment Limited | Administrative & support | 2022 |
| Tsrm Training Ltd | Administrative & support | 2024 |
| TTS Group Limited | Information & communication | 2002 |
| Tubney Limited | Hospitality | 2021 |
| Tubney Woods | Agriculture & fishing | 1999 |
| Tuckman Marsh Ltd | Information & communication | 2019 |
| Tulip Accounts Ltd | Administrative & support | 2013 |
| Tune-Rite Auto Services Limited | Wholesale & retail | 2018 |
| Tuner-Fish Luglocks Limited | Manufacturing | 2005 |
| Tuner-Fish Rights Limited | Arts & recreation | 2005 |
| Turaga Consulting Ltd | Professional & scientific | 2022 |
| Turn to Dust Ltd | Arts & recreation | 2022 |
| Turner FS Ltd | Professional & scientific | 2018 |
| Turnkey Installations Ltd | Construction | 2025 |
| Turnpike Filling Station (CH) Limited | Real estate | 1978 |
| Tutton Russell Consulting Ltd | Information & communication | 2013 |
| Twickenham House (Abingdon) Management Company Limited | Households | 2011 |
| Twin Grapes Limited | Professional & scientific | 2023 |
| Twins Building Ltd | Construction | 2026 |
| Twins Decoration Limited | Construction | 2026 |
| TXD Limited | Information & communication | 2005 |
| TY Ecommerve Services Ltd | Wholesale & retail | 2025 |
| Tyber's Reggae Lounge Ltd | Hospitality | 2020 |
| Typeworks Ltd | Information & communication | 2026 |
| Tyrells 1956 Limited | Extraterritorial | 2014 |
| UA92 Global Limited | Education | 2020 |
| UBB Bros Limited | Wholesale & retail | 2025 |
| Uchechukwu ANU Ltd | Health & social care | 2019 |
| Udma Ltd | Professional & scientific | 2023 |
| Uhcineulhqsit Limited | Financial services | 2024 |
| UHS Group Limited | Manufacturing | 2012 |
| UJA World Limited | Hospitality | 2025 |
| Ujji Ltd | Information & communication | 2020 |
| UK Fast IS Slow Ltd | Wholesale & retail | 2026 |
| UK Fusion Energy Ltd | Administrative & support | 2023 |
| UK Fusion Solutions Ltd | Administrative & support | 2022 |
| Ukaea Ltd | Administrative & support | 2022 |
| Ukey Consulting Group Ltd | Information & communication | 2020 |
| Ultra Stones Oxford Ltd | Construction | 2023 |
| Umdasch Store Makers United Kingdom Ltd | Manufacturing | 1999 |
| Unasis International Limited | Wholesale & retail | 2012 |
| Unesta Ltd | Construction | 2023 |
| Uniminepool Ltd | Wholesale & retail | 2026 |
| Uninest Homes Limited | Real estate | 2025 |
| Unique Retail Group Ltd. | Wholesale & retail | 2003 |
| United Kingdom Real Estate Limited | Real estate | 2025 |
| Universe City of Oxford Ltd | Information & communication | 2022 |
| UP for Change Ltd | Professional & scientific | 2009 |
| Uppsoft Technology Ltd | Wholesale & retail | 2025 |
| Uprising Games Limited | Information & communication | 2008 |
| Upwey Estates Limited | Construction | 2003 |
| Upworking Limited | Other services | 2025 |
| Uquotient Ltd | Professional & scientific | 2025 |
| Usama Awais Limited | Wholesale & retail | 2026 |
| Usefy Ltd | Wholesale & retail | 2026 |
| Usky Ltd | Wholesale & retail | 2025 |
| Utopia Beauty Salon Ltd | Other services | 2017 |
| V G Studio Limited | Professional & scientific | 2019 |
| V Industries Ltd | Wholesale & retail | 2019 |
| V3MVK Limited | Professional & scientific | 2021 |
| Vahana Consulting Limited | Administrative & support | 2015 |
| VAL Courier Limited | Transport & logistics | 2022 |
| Vale Site Solutions Ltd | Real estate | 2021 |
| Vale Transport Planning Ltd | Professional & scientific | 2013 |
| Valentine Bloodstock Limited | Agriculture & fishing | 2020 |
| Valley Barbers Limited | Other services | 2016 |
| Value Adage Limited | Professional & scientific | 2015 |
| Valugen Ltd | Professional & scientific | 2007 |
| Vangardening Limited | Administrative & support | 2018 |
| Varen Consulting Ltd | Professional & scientific | 2017 |
| Varen Property Limited | Real estate | 2019 |
| Vasudev Properties Limited | Construction | 2016 |