| Oaktree Capital Management (UK) LLP | London | A rating |
| Oaktree Farm Care Ltd | Horsham | A rating |
| Oaktree Power Limited | London | A rating |
| Oaktree Support Services | Blackpool | A rating |
| Oakvale Capital LLP | London | A rating |
| Oakview Care Home Limited | Birmingham | A rating |
| Oakville Care Limited | Cardiff | A rating |
| Oakwood Care Operations LTD | Fakenham | A rating |
| Oakwood Community School | Bagworth | A rating |
| Oakwood Engineering Solutions Ltd | Salford | A rating |
| Oakwood House (Norwich) Ltd | Norwich | A rating |
| Oakwood Park Grammar School | Maidstone | A rating |
| Oakwood Physiotherapy & Wellness Centre | Bingham, Notts | A rating |
| Oakwood Properties (UK) Ltd T/A LHL Estates | Finsbury Park | A rating |
| Oakwood Resources Limited | London | A rating |
| Oakwood Surgery | Birmingham | A rating |
| Oakwood Surgery | Mansfield Woodhouse | A rating |
| OAKWORTH FURNITURE LIMITED | PORTSMOUTH | A rating |
| OAKWORTH MANOR RESIDENTIAL HOME LIMITED | Keighley | A rating |
| OAM CHILDREN'S CENTRE LTD | London | A rating |
| OANDA Europe Limited | London | A rating |
| Oando Logistics & Services Limited | London | A rating |
| OAOA | London | A rating |
| OAS&CO ACCOUNTING LTD | London | A rating |
| Oases Limited | Oldham | A rating |
| Oasis Accountants Limited | London | A rating |
| OASIS BANQUETING LTD. | BARKING | A rating |
| Oasis Brothers Ltd | London | A rating |
| Oasis Care Solutions Ltd. | St. Ives | A rating |
| Oasis Care-UK Limited | Chelmsford | A rating |
| Oasis Christian Fellowship | Aberdeen | A rating |
| Oasis Community Learning | London | A rating |
| Oasis Convenience Store | Portsmouth | A rating |
| Oasis Crescent (UK) Ltd | London | A rating |
| Oasis Crescent Wealth (UK) Limited | London | A rating |
| OASIS DESIGN AND BUILD LTD | London | A rating |
| Oasis Domestic Abuse Service | Margate | A rating |
| OASIS FORTE HEALTHCARE LIMITED | Huddersfield | A rating |
| Oasis Good Games UK Limited | London | A rating |
| OASIS HEALTH AND WELLNESS GROUP LTD | Bury | A rating |
| Oasis Healthcare Limited | Bristol | A rating |
| Oasis Healthcare Solutions Ltd | BOURNEMOUTH | A rating |
| OASIS HOMECARE SERVICES LTD | Hayes | A rating |
| Oasis Hotel (Harlow) Limited | Harlow | A rating |
| Oasis Hotels Ltd | London | A rating |
| Oasis in the park LTD | Liverpool | A rating |
| Oasis Land Development Ltd | Southport | A rating |
| Oasis Manor Ltd | Croydon | A rating |
| OASIS OF LOVE INTERNATIONAL CENTRE | Wolverhampton | A rating |
| Oasis Outlet Ltd | Nottingham | A rating |
| OASIS PIZZA AND KEBAB LTD | Dudley | A rating |
| Oasis Places Ltd | llford | A rating |
| Oasis Pro Limited | Chinnor | A rating |
| Oasis Retail Ltd T/a Budgens | Rugby | A rating |
| Oasis South Ltd T/A Eco Natural Products | Poole | A rating |
| OASIS SPA LTD | Birmingham | A rating |
| Oasis Stores | Sheerness | A rating |
| OASIS STUDIOS LIMITED | LONDON | A rating |
| oasis support Ltd | NEWPORT | A rating |
| Oasis Takeaway (Nottingham) Ltd | Nottingham | A rating |
| OASIS-CARE UK GROUP LIMITED | Derby | A rating |
| Oat Services Ltd | Southampton | A rating |
| Oathall Veterinary Group Ltd | Haywards Heath | A rating |
| Oatlands Park Hotel | Weybridge | A rating |
| OATLEIGH CARE LTD | LONDON | A rating |
| Oatly UK Ltd | Farringdon | A rating |
| Oaxaca Limited | London | A rating |
| Oaza European Foods Ltd | Leeds | A rating |
| OB Capital Limited t/as Hyde | London | A rating |
| OB Media Partners Limited | London | A rating |
| OB UK Holdings Limited | Bromley | A rating |
| OBAID INVESTMENTS LIMITED | London | A rating |
| Oban Congregational Church | Oban | A rating |
| Oban Dental and Implant Centre | Oban | A rating |
| Oban Specsavers Limited | Oban | A rating |
| OBAS Group Limited | London | A rating |
| Obaseki & Co LTD | London | A rating |
| Obatos Care Services Limited | Birmingham | A rating |
| Obayashi Properties UK Limited | London | A rating |
| Obcon Solutions Ltd | Crewe | A rating |
| OBD GLOBAL LTD | London | A rating |
| OBE London Limited | London | A rating |
| Obelisk Legal Support Solutions Limited | London | A rating |
| Obelisk Networks (UK) Ltd | Fareham | A rating |
| Oberix Group Ltd | London | A rating |
| Oberlanders Architects LLP | Edinburgh | A rating |
| Oberlanders Group LLP | Edinburgh | A rating |
| Oberon Investments Group PLC | London | A rating |
| Obex Group Limited | Dunstable | A rating |
| OBG Company Limited | Liverpool | A rating |
| Object and Animal Limited | London | A rating |
| Object and Animal Ltd | London | A rating |
| Objective Care Ltd | Southall | A rating |
| Objective Corporation UK Ltd | Reading | A rating |
| OBJECTIVE LOGISTICS LTD | Essex | A rating |
| Objectivus Financial Consulting | London | A rating |
| OBJECTMASTERY (UK) LIMITED | London | A rating |
| Objectway Limited | Birmingham | A rating |
| OBJECTYL LTD | London | A rating |
| Oblates of Mary Immaculate | London | A rating |
| Oblates of the Assumption | London | A rating |
| Oblige Care Services Ltd | Feltham | A rating |
| OBLIGEITSOLUTIONS LIMITED | Hale | A rating |
| OBLIQUE BEAUTY HOUSE LIMITED | London | A rating |
| OBM (UK) Limited | London | A rating |
| OBM ONELAB CIC | London | A rating |
| Obo Limited | London | A rating |
| OBON FOODS LTD | Kingston Upon Thames | A rating |
| OBR Construction Limited | High Wycombe | A rating |
| OBRIDGE REALTY LTD | Leeds | A rating |
| OBRIZUM GROUP Ltd | Cambridge | A rating |
| OBRRO LIMITED | Essex | A rating |
| OBS Facilities LTD | Heston | A rating |
| OBS Hotel Limited | London | A rating |
| OBS Medical | Cirencester | A rating |
| Observational and Pragmatic Research International Ltd | Sankence | A rating |
| OBSERVATORY NEWS SLOUGH LIMITED | Slough | A rating |
| Observe Care Limited | Eastleigh | A rating |
| Obsidian Archernar | London | A rating |
| Obsidian Healthcare Group | Milton Keynes | A rating |
| OBSIDIANOS LIMITED | London | A rating |
| Obso Ltd | Stafford | A rating |
| Obviously Group Ltd | Maidenhead | A rating |
| OBY ENTERPRISES LIMITED | Glasgow | A rating |
| OC Physio Ltd T/A Bodyset | London | A rating |
| OC&C Strategy Consultants | London | A rating |
| Ocado Central Services Limited | Hatfield | A rating |
| Ocado Retail Limited | Hatfield | A rating |
| OCaml Labs Consultancy Limited | Cambridge | A rating |
| Ocasa Management Limited | Manchester | A rating |
| OCASO S.A.SEGUROS Y REASEGUROS | Godalming | A rating |
| Ocasta Studios Limited | Harpenden | A rating |
| OCCA | Glasgow City | A rating |
| OCCA House Ltd | Oxford | A rating |
| Occam Biosciences Limited | Dundee | A rating |
| Occam Underwriting Limited | London | A rating |
| OccamSec Ltd | Edinburgh | A rating |
| Occhiali Limited | Clerkenwell, London | A rating |
| Occidental of Algeria LLC | London | A rating |
| OCCUITY LTD | Reading | A rating |
| OCCULT FOX LTD | Perth | A rating |
| Occupancy Marketing Limited trading as 80 Days | Edinburgh | A rating |
| Occupational Personnel Services Ltd | London | A rating |
| OCEAN & CO (PVT) LIMITED | Manchester | A rating |
| ocean 14 capital | London | A rating |
| Ocean Bites Ltd T/A Yo! Sushi & Panku | Warwick | A rating |
| Ocean Blue Colours Ltd | Cookham | A rating |
| Ocean Blue Software Limited | Bristol | A rating |
| Ocean Boat Fish & Chips | Stourbridge | A rating |
| OCEAN BREEZE RESIDENTIAL CARE HOME | HAMPSHIRE | A rating |
| Ocean Care Services Ltd | Blackpool | A rating |
| Ocean Catch London LTD | Fulham | A rating |
| Ocean Construction Services Ltd | London | A rating |
| Ocean Dine Ltd T/A Indian Ocean Restaurant | Theydon Bois | A rating |
| Ocean Endeavour Ltd | Peterhead | A rating |
| Ocean Films Ltd | Godstone | A rating |
| OCEAN FISH (RETAIL) LIMITED | St. Austell | A rating |
| Ocean Fishing LLP | Fraserburgh | A rating |
| Ocean Generation | London | A rating |
| Ocean Hare Limited | Poole | A rating |
| Ocean Hope Ltd | Wrexham | A rating |
| Ocean Infinity Group Limited | London | A rating |
| Ocean Installer Limited | Aberdeen | A rating |
| OCEAN INTERNATIONAL RE LIMITED | London | A rating |
| Ocean Island Ltd | London | A rating |
| Ocean King Ltd | Derby | A rating |
| Ocean LED Marine Ltd | Hinckley | A rating |
| Ocean Ledger Ltd | Eastbourne | A rating |
| Ocean Mediart Ltd | London | A rating |
| OCEAN MONSTER CHARING CROSS LTD | London | A rating |
| Ocean Network Express (Europe) Limited | London | A rating |
| OCEAN PACIFIC SHIPPING LINE UK LTD-14703068 | LONDON | A rating |
| Ocean Partners UK Limited | Maidenhead | A rating |
| Ocean Pearl 29 Ltd | Worksop | A rating |
| Ocean Phoenix International Limited | Inverurie | A rating |
| Ocean Platter Ltd T/A Ocean Fish Platter | Ipswich | A rating |
| Ocean Prime Industries Ltd | St Albans | A rating |
| Ocean Science Consulting Ltd | Dunbar | A rating |
| Ocean Shore One Ltd | Bedford | A rating |
| Ocean Signal Limited | Margate | A rating |
| OCEAN TIDE (UK) LIMITED | London | A rating |
| Ocean Tide Wealth Ltd | London | A rating |
| OCEAN TRADING INTERNATIONAL LIMITED | Manchester | A rating |
| Ocean Travels Ltd | Bolton | A rating |
| Ocean Way Hospitality Services Limited | London | A rating |
| Ocean Wide Logistics UK Ltd | Daventry | A rating |
| Ocean Winds UK Ltd | Edinburgh | A rating |
| Ocean Youth Trust North | Berwick upon Tweed | A rating |
| OCEAN'S 11 LTD | Leigh | A rating |
| Oceandusk Group Limited | London | A rating |
| Oceaneering International Services Limited | Aberdeen | A rating |
| Oceanic Care Services Ltd. | Barking | A rating |
| Oceanic Drifter Fishing Ltd | Plymouth | A rating |
| Oceanic International Shipping UK Ltd | Richmond | A rating |
| Oceanic Technologies Limited | Watford | A rating |
| Oceanictrade Limited | London | A rating |
| Oceanix International Ltd | Surrey | A rating |
| Oceanmart Limited T/A Kenroyal Nursing Home | Northamptonshire | A rating |
| OceanMind Limited | Didcot | A rating |
| Oceans Care Services Ltd | Birmingham | A rating |