| Owen Fabrications Ltd | Greenford | A rating |
| Owen Farming Transport Ltd | Bury St Edmunds | A rating |
| Owen Mumford | Woodstock | A rating |
| OWENS CORNING VEIL UK LTD | LIVERSEDGE | A rating |
| Owey Enterprises | portrush | A rating |
| Owkin UK Ltd | London | A rating |
| OWL PROFESSIONAL SERVICES LIMITED | Chelmsford | A rating |
| Owl Ventures Management UK Limited | London | A rating |
| OWLSTONE MEDICAL LTD | CAMBRIDGE | A rating |
| Own Designs Ltd | Mitcham | A rating |
| Own Hold Construction Ltd | Ilford | A rating |
| Own Ltd | Aylesbury | A rating |
| Own Your Space Limited | Bolton | A rating |
| Own-Kind Ltd | London | A rating |
| OWON SMARTTEK LTD | Burscough | A rating |
| OWTON FISHERIES LTD | Hartlepool | A rating |
| OX BRASSERIE LTD | Southampton | A rating |
| OX MARKETING LTD | Southsea | A rating |
| Ox Mountain Limited | Oxford | A rating |
| OX PRODUCTS GROUP UK LTD | London | A rating |
| Ox Support Services Ltd. | Ascot | A rating |
| OX&K LTD | CWMBRAN | A rating |
| Oxa Autonomy Limited | Oxford | A rating |
| Oxalis Games Ltd | London | A rating |
| Oxbay Ltd | Harrogate | A rating |
| Oxbow Partners Limited | London | A rating |
| Oxbridge Academy Ltd | London | A rating |
| OxBridge Centre (UK) Ltd | New Malden | A rating |
| OXBRIDGE EDUCATION GROUP LIMITED | Reading | A rating |
| OXBRIDGE GROUP LTD | London | A rating |
| Oxbridge International Education Ltd | High Wycombe | A rating |
| Oxbridge Mobile Tyre Fitting Ltd | Stockton On Tees | A rating |
| Oxbury Bank PLC | Chester | A rating |
| OXBYTE TECH LIMITED | Oxford | A rating |
| OXCCU Tech Ltd | Begbroke | A rating |
| OXECO U.K. Limited | Yarnton | A rating |
| Oxedent Marketing Ltd | Ilford | A rating |
| Oxehealth Ltd | Abingdon | A rating |
| Oxentia Ltd | Oxford | A rating |
| Oxenwood Real Estate LLP | London | A rating |
| Oxera Consulting LLP | Oxford | A rating |
| Oxfam GB | Oxford | A rating |
| OXFORD ACADEMY LONDON LTD | London | A rating |
| Oxford ADHD Centre Ltd | Headington | A rating |
| Oxford Algorithms Ltd | Oxford | A rating |
| Oxford Analytica | Oxford | A rating |
| Oxford and Cambridge Club | London | A rating |
| Oxford Architects LLP | Bristol | A rating |
| Oxford BioDynamics | Oxford | A rating |
| Oxford BioMedica (UK) Ltd | Oxford | A rating |
| Oxford BioTherapeutics Ltd | Oxford | A rating |
| Oxford Brain Diagnostics Ltd | Oxford | A rating |
| Oxford Brookes University | Oxford | A rating |
| OXFORD BUDDHA VIHARA | OXFORD | A rating |
| OXFORD BUFFET LTD | Oxford | A rating |
| OXFORD CANCER ANALYTICS LTD | Oxford | A rating |
| Oxford Cancer Biomarkers Limited | Oxford | A rating |
| Oxford Cardiomox Ltd | Oxford | A rating |
| OXFORD CARE HOMES LIMITED T/A FAIRHOLME HOUSE | BANBURY | A rating |
| OXFORD CARE SERVICES LTD | Hounslow | A rating |
| Oxford Carpets & Furniture Ltd | Oxford | A rating |
| Oxford Centre for Islamic Studies | Oxford | A rating |
| Oxford Centre for Mission Studies | Oxford | A rating |
| Oxford Centre for Religion and Public Life | Oxford | A rating |
| Oxford College of Business | London | A rating |
| Oxford College of Education Lt | HIGH WYCOMBE | A rating |
| Oxford Comma Advisory Ltd | London | A rating |
| Oxford Cricket Club | Oxford | A rating |
| Oxford DataPlan Limited | London | A rating |
| Oxford Dental Care Ltd | Oxford | A rating |
| Oxford Diocesan Board of Finance | Kidlington | A rating |
| Oxford Diocesan Bucks Schools Trust | Stoke Mandeville | A rating |
| Oxford Diocesan Schools Trust | Wantage | A rating |
| Oxford Downs Cricket Club | Witney | A rating |
| OXFORD ECONOMICS LTD | OXFORD | A rating |
| Oxford Evangelical Presbyterian Church CIO | Oxford | A rating |
| Oxford Expression Technologies Ltd | Oxford | A rating |
| Oxford Fertility Unit Ltd | Oxford | A rating |
| OXFORD FLOORS AND TILES LTD | Oxford | A rating |
| Oxford Flow | Oxford | A rating |
| OXFORD FRUITS & VEG LTD T/A Oxford Food Service | Oxford | A rating |
| Oxford Gene Technology IP Limited | Kidlington | A rating |
| Oxford Genetics Limited | London | A rating |
| Oxford Genetics Ltd | Oxford | A rating |
| Oxford Global Projects UK Limited | Oxford | A rating |
| OXFORD GOLDENLINK LIMITED | London | A rating |
| Oxford Graduate School Ltd | London | A rating |
| OXFORD GUEST HOUSE LIMITED | Oxford | A rating |
| Oxford Health NHS Foundation Trust | Oxford | A rating |
| Oxford Health Solutions Limited | Oxford | A rating |
| Oxford Healthspan LTD | Oxford | A rating |
| Oxford Heartbeat Limited | London | A rating |
| OXFORD HOMEWARE LTD | Birmingham | A rating |
| OXFORD HOSPITALITY SERVICES(UK) LTD T/A OXO BAR AND HOTEL | OXFORD | A rating |
| Oxford House College Training Limited | London | A rating |
| Oxford House Community Care | Farnham Royal | A rating |
| Oxford House Veterinary Clinic Ltd | Tonypandy | A rating |
| Oxford HR | Oxford | A rating |
| Oxford Immune Algorithmics Ltd | Reading | A rating |
| Oxford Immunotec Limited T/A Revvity | Abingdon | A rating |
| Oxford Indices Ltd | High Wycombe | A rating |
| Oxford Information Labs Ltd | Oxford | A rating |
| OXFORD INNOVATION CONSULTING LTD | Malvern | A rating |
| Oxford Innovation Ltd | Oxford | A rating |
| Oxford Institute for Energy Studies | Oxford | A rating |
| Oxford Instruments Nanotechnology Tools Limited | Abingdon | A rating |
| Oxford International Education & Travel Ltd | London | A rating |
| Oxford International School | Oxford | A rating |
| Oxford International Study Abroad Programme Ltd | Oxford | A rating |
| Oxford Investment Consultants LLP | Oxford | A rating |
| Oxford Ionics Limited | Kidlington | A rating |
| Oxford Kilburn Youth Trust | London | A rating |
| Oxford Kitchens and Bathrooms ltd | Bladon | A rating |
| OXFORD KOREAN CHURCH | OXFORD | A rating |
| Oxford Lasers Limited | Didcot | A rating |
| Oxford Leadership Academy Limited | London | A rating |
| Oxford Leisure Ltd | Oxford | A rating |
| Oxford Measured Limited | Oxford | A rating |
| OXFORD MEDIA SOLUTIONS LIMITED | Oxford | A rating |
| Oxford Medical Products | Witney | A rating |
| Oxford Medical Simulation | London | A rating |
| Oxford Mestar Ltd | Oxford | A rating |
| Oxford Metrics plc | Oxford | A rating |
| OXFORD MOBILES & COMPUTERS LTD | Oxford | A rating |
| Oxford Montessori Schools Limited | Oxford | A rating |
| Oxford Nanoimaging Ltd | Oxford | A rating |
| Oxford Nanopore Technologies plc. | Oxford | A rating |
| Oxford NanoScience Ltd | Abingdon | A rating |
| Oxford nanoSystems Ltd | Abingdon | A rating |
| Oxford Off Licence Ltd | Oxford | A rating |
| OXFORD ONLINE SCHOOL LTD | Oxford | A rating |
| Oxford Philharmonic Orchestra Productions | London | A rating |
| Oxford Photovoltaics Limited | Oxford | A rating |
| Oxford Policy Management Limited | Oxford | A rating |
| Oxford Polo Limited | Bicester | A rating |
| Oxford Prime Ltd | Wimbeldon | A rating |
| Oxford Private Care Limited | Oxford | A rating |
| Oxford Properties Management (UK) Limited | London | A rating |
| OXFORD QUALITY CENTRE LIMITED | Robertsbridge | A rating |
| Oxford Quantum Circuits Limited | Reading | A rating |
| Oxford RF Solutions Ltd | Didcot | A rating |
| OXFORD RISK LIMITED | LONDON | A rating |
| Oxford Robotics Ltd trading as Dynium Robot | Reading | A rating |
| Oxford Royale Academy | Oxford | A rating |
| Oxford Scholastica Academy Ltd | London | A rating |
| Oxford School of English | Oxford | A rating |
| OXFORD SCIENCE ENTERPRISES PLC | Oxford | A rating |
| Oxford Semantic Technologies Limited | Oxford | A rating |
| Oxford Sigma Limited | Oxford | A rating |
| Oxford Space Systems Ltd | Harwell Oxford | A rating |
| Oxford Specsavers Limited | Oxford | A rating |
| Oxford Stadium Ltd | Oxford | A rating |
| Oxford Summer Courses Limited | Oxford | A rating |
| Oxford Terrace & Rawling Road Medical Group | Newcastle Upon Tyne | A rating |
| Oxford Tiles Limited | Oxford | A rating |
| Oxford United Football Club Limited | Oxford | A rating |
| Oxford University Hospitals NHS Trust | Oxford | A rating |
| Oxford University Press | Oxford | A rating |
| Oxford Vintage Limited | Oxford | A rating |
| Oxfordshire Communications Limited | Dewsbury | A rating |
| Oxfordshire Community Churches | Osney Mead | A rating |
| Oxfordshire County Council | Oxford | A rating |
| Oxfordshire Crossroads | Oxford | A rating |
| OXFORDSHIRE MIND | Oxford | A rating |
| Oxfordshire Newmedica Limited | Abingdon | A rating |
| Oxhey Property Limited | Harrow | A rating |
| Oxhey Property Management Limited | Harrow | A rating |
| OXHEY UK INVESTMENTS LTD | Harrow | A rating |
| Oxheypharm Limited | Watford | A rating |
| OXIJAN LTD | Bolton | A rating |
| Oxilio Limited | Southmoor | A rating |
| Oxiway Limited t/a MeVitae | Didcot | A rating |
| Oxkem Limited | Reading | A rating |
| Oxlane Food Centre Ltd | Dagenham | A rating |
| Oxleas NHS Foundation Trust | Dartford | A rating |
| Oxley Developments Company Limited | Ulverston | A rating |
| OXLOW PHARMACY | DAGENHAM | A rating |
| Oxmit Technologies Limited | Cheadle | A rating |
| OXO21 LTD | Windsor | A rating |
| Oxoid Limited | Basingstoke | A rating |
| Oxomoron Ltd | London | A rating |
| OXON SERVICES MANAGEMENT LTD | Slough | A rating |
| Oxon Traders LTD | OXFORD | A rating |
| OXONS COLLEGE LIMITED | London | A rating |
| Oxphen Premium Management Ltd | Sheffield | A rating |
| Oxshott Village Store | Leatherhead | A rating |
| OxSonics Limited | Oxford | A rating |
| OXTED AIM LTD | Crawley | A rating |
| Oxted House Limited | Oxted, Surrey | A rating |
| OXTON BOOZE RETAIL LTD | Merseyside | A rating |
| OXTON MANOR LTD | Merseyside | A rating |
| Oxvalue.AI Limited | Oxfordshire | A rating |
| OXY ORIENTAL LIMITED | Oxford | A rating |
| oXya UK Limited | Southampton | A rating |
| Oxygen Access Project | Mildenhall | A rating |
| Oxygen House | Exeter | A rating |
| Oxygene Ltd | Wolverhampton | A rating |
| Oxygy Limited | London | A rating |
| Oyak Global Risk Services Limited | London | A rating |
| OYNB Limited | London | A rating |