| BEP Enterprises Limited | Real estate | 1957 |
| Bespoke Stonemasonry Services Ltd | Construction | 2017 |
| Bethel Estates Ltd | Real estate | 2023 |
| BH Hold LLP | | 2024 |
| Bicester Continental Market Ltd | Wholesale & retail | 2020 |
| Bicester Land Rovers Limited | Extraterritorial | 2011 |
| Big Fear Limited | Information & communication | 2024 |
| Biggerplate.Com Ltd | Information & communication | 2007 |
| Biggles Hair Studio Limited | Other services | 2013 |
| Binsey Lane Management Company Limited | Households | 2003 |
| Bio-Rad ABD Serotec Ltd | Manufacturing | 1981 |
| Biome Australia Trading UK Limited | Wholesale & retail | 2023 |
| Biosphere Alternative Technologies Ltd | Information & communication | 2021 |
| Birdi & Kumar Property Limited | Real estate | 2018 |
| Biryani Magic Limited | Hospitality | 2023 |
| Black Dog Design Limited | Professional & scientific | 2002 |
| Black Mountain Resorts Limited | Real estate | 2006 |
| Blenheim Court (Oxford) Limited | Households | 2003 |
| Blenheim DRY Stone Walling Limited | Construction | 2014 |
| Blenheim Wealth Management Limited | Financial services | 1999 |
| Bletchingdon Park Mews Management Limited | Households | 1991 |
| Blomoor Property Ltd | Real estate | 2025 |
| Blue EYE Holdings Ltd | Information & communication | 2024 |
| Blueprint London Design and Build Limited | Construction | 2026 |
| Bluie Skies Limited | Transport & logistics | 2021 |
| Blushes Hair Limited | Other services | 2021 |
| BLX Studios Ltd | Information & communication | 2019 |
| Bodypaint Creative Ltd | Arts & recreation | 2025 |
| Bookbinders Court Management Company Limited | Households | 2005 |
| Bota Dema Taxis Ltd | Transport & logistics | 2025 |
| Boundary Close Court Residents Association Limited | Households | 1974 |
| Bowood Court Management Company Limited | Households | 2007 |
| Bradgate Capital Ltd | Professional & scientific | 2024 |
| Bramble Homes Ltd | Real estate | 2019 |
| Brasilatte Coffee Ltd | Hospitality | 2024 |
| Bread and Butter Creative Limited | Professional & scientific | 2013 |
| Breeches END (Cumnor Hill) Management Limited | Households | 2008 |
| Briash Holdings Limited | Real estate | 2017 |
| Brice Robinson Holdings Ltd | Financial services | 2020 |
| Brice Robinson Limited | Other services | 2016 |
| Brick & Beam Construction Ltd | Construction | 2025 |
| Brick House Barns (Greete) Management Company Limited | Households | 2026 |
| Bridge View Management Company Limited | Households | 1998 |
| Bridgeforce Limited | Other services | 2011 |
| Bright Properties (Oxford) Ltd | Real estate | 2019 |
| Bright Smart Cleaner Limited | Administrative & support | 2021 |
| Brightside Urban Estates Limited | Real estate | 2026 |
| Britania Shield Roofing Ltd | Construction | 2026 |
| Broadribb Cycles Limited | Wholesale & retail | 2010 |
| Broadribb Limited | Wholesale & retail | 1936 |
| Broadribb Property Limited | Real estate | 2012 |
| Broadwater Place (Wantage) Management Company Limited | Households | 2018 |
| Broadway Butchers (Didcot) Limited | Wholesale & retail | 2006 |
| Broche Bakery Ltd | Manufacturing | 2023 |
| Broche Coffee Ltd | Manufacturing | 2023 |
| Broche Headington Ltd | Manufacturing | 2025 |
| Brookside Court (Woodstock) Limited | Households | 1998 |
| Brookwood Accountancy Limited | Professional & scientific | 1999 |
| Brookwood House Kidlington (Oxford) Management Company Limited | Households | 2005 |
| Brothertons of Woodstock Limited | Real estate | 1997 |
| Building Workforce Limited | Administrative & support | 2015 |
| Burberry House (Kidlington) Management Company Limited | Households | 2014 |
| Burger N Co Ltd | Hospitality | 2025 |
| Bursledene Limited | Other services | 2016 |
| Buttar Shield Ltd | Wholesale & retail | 2026 |
| C & G Holdings & Investments Ltd | Real estate | 2025 |
| C G Josephs & Sons Ltd | Professional & scientific | 2010 |
| C J Twomey Engineering Ltd. | Construction | 1997 |
| C S Boswell Holdings Ltd | Real estate | 2021 |
| C.H.P. Design Services Limited | Professional & scientific | 1981 |
| C.T.Denton Ltd | Other services | 2024 |
| Cablesson Limited | Wholesale & retail | 2011 |
| Cablewise Communications & Systems Ltd | Information & communication | 2020 |
| Caine Utility Services Ltd | Construction | 2024 |
| Calleblend Limited | Real estate | 1999 |
| CAM Muldur Contracting Ltd | Construction | 2026 |
| Camp Energy Limited | Arts & recreation | 2014 |
| Cannons Property Services Limited | Real estate | 2017 |
| Capital Air Services Limited | Transport & logistics | 1994 |
| Capon Bros Electrical Ltd | Construction | 2023 |
| Careerademicals Ltd | Education | 2024 |
| Carl Boswell Ltd | Other services | 2014 |
| Carnhill Transformers Limited | Manufacturing | 1985 |
| Carpenter's(Dulwich),Limited | Real estate | 1940 |
| Cat Kidlington Limited | Hospitality | 2024 |
| Cathedral Homes (Beaconsfield) Limited | Construction | 2006 |
| Cathedral Homes (Corfton) Limited | Construction | 2025 |
| Cathedral Homes (Dorset) Limited | Construction | 2020 |
| Cathedral Homes (Missenden) Limited | Real estate | 2023 |
| Cathedral Homes (Shropshire) Limited | Real estate | 2023 |
| Cathedral Homes (South Heath) Limited | Construction | 2025 |
| Cathedral Homes (U.K.) Limited | Real estate | 1997 |
| Catherine Henderson Consultants Limited | Information & communication | 1995 |
| Cavendish Place (Oxford) Management Limited | Households | 1996 |
| Cazalmay Ltd | Information & communication | 2026 |
| CDP Carpentry and Construction Ltd | Construction | 2023 |
| CDP Technical Consulting Limited | Information & communication | 2025 |
| Ceaking Solutions LLP | | 2014 |
| Centurion Court (Bicester) Management Limited | Real estate | 2015 |
| CERTIS24 Limited | Professional & scientific | 2015 |