| OYO Technology and Hospitality (UK) Ltd | London | A rating |
| OYSLANS FORECOURT ENGINEERING LIMITED T/A GULF | Birmingham | A rating |
| OYSTER DESIGN AND CONSTRUCTION LTD | London | A rating |
| OYSTER GLOBAL SERVICES LTD` | Thornton Heath | A rating |
| Oyster IMS Ltd | London | A rating |
| Oyster North East Ltd t/a The Golden Fry | Middlesbrough | A rating |
| Oyster Supported Living & Domicilary Care LTD | London | A rating |
| Oyster Yachts Limited | Southampton | A rating |
| OYSTERBLINK UK LTD | Chelmsford | A rating |
| Oystermen Events Limited | London | A rating |
| OYTAS UK LTD | London | A rating |
| OZ club Ltd | London | A rating |
| Oz Equine Ltd | Guildford | A rating |
| OZ IT CONSULTANCY LTD | London | A rating |
| OZ LEICESTER LTD T/A SUBWAY | Wigston | A rating |
| OZ ORGANISATIONS LTD | London | A rating |
| Oza Design Limited | London | A rating |
| Ozan Distributors Ltd | Blackburn | A rating |
| Ozan Limited | London | A rating |
| OZCAN LIMITED | London | A rating |
| OZE INDUSTRY LIMITED | Hoddesdon | A rating |
| OZEL GROUP LTD | Essex | A rating |
| Ozgun Limited | London | A rating |
| OZGUR NAVRUZ T/A CATCH FISHERIES | LYTHAM ST ANNES | A rating |
| OZKAYA SERVICES LIMITED T/A Lokma Patisserie | London | A rating |
| Ozland Limited | Yiewsley | A rating |
| OZLU 27 LTD T/A Mezze Bar and Grill | Canterbury | A rating |
| Ozmen Ltd | Sheffield | A rating |
| OZON CONSTRUCTION LTD | Ilford | A rating |
| OZONE AMD LIMITED T/A OZONE RESTAURANT | ALDERSHOT | A rating |
| OZONE AUTO LTD | Coventry | A rating |
| Ozone Coffee Roasters UK Limited | London | A rating |
| Ozone Financial Technology Limited | London | A rating |
| Ozone Laundry Limited | Wembley | A rating |
| Ozone Project Limited | London | A rating |
| Ozone Stores LTD | Loughborough | A rating |
| Ozumba Training and Consultancy Services Limited trading as EMINENT DOMICILIARY CARE AGENCY | Croydon | A rating |
| OZUN LTD T/A The Chippy Fish & Chips | Finsbury Park, | A rating |
| Ozyakut Ltd | London | A rating |
| OZZ LIMITED | London | A rating |
| OZZAS LTD | East Tilbury | A rating |
| Ozzy Barbers | Newport | A rating |
| Ozzy Development Ltd | London | A rating |
| Ozzy's Newsagent & Minimart Limited | London | A rating |