| Orbis Investments (U.K.) Limited | London | A rating |
| Orbis Portfolio Management (Europe) LLP | London | A rating |
| Orbit Fab Ltd | Didcot | A rating |
| Orbit Partners Limited | London | A rating |
| Orbital Gas Systems Limited | Stone | A rating |
| Orbital Materials Ltd | Elsted | A rating |
| Orchard Global Asset Management LLP | London | A rating |
| Orchard Therapeutics (Europe) Limited | London | A rating |
| OREAN PERSONAL CARE LIMITED | Cleckheaton | A rating |
| Orege UK Limited | Stoke-on-Trent | A rating |
| Oremus Accountants Limited | Wirral | A rating |
| Organon Pharma (UK) Limited | Cramlington | A rating |
| OrganOx Limited | Oxford | A rating |
| Orgvue Limited | London | A rating |
| Orica UK Ltd | Warrington | A rating |
| ORIENT CABLE (NBO UK) LTD. | London | A rating |
| Oriental Food Express Limited | Shrewsbury | A rating |
| ORIFLAME INVESTMENT HOLDING PLC | London | A rating |
| Origami Risk Ltd | London | A rating |
| Origin Frames Limited | High Wycombe | A rating |
| Origin Wine Ltd | Banbury | A rating |
| Original Travel Company Ltd | London | A rating |
| Orion (GB) Limited | Southall | A rating |
| Orion Capital Managers (UK) Limited | London | A rating |
| Orion Engineering Services Limited | Inverness | A rating |
| Orion Global Advisors UK Limited | London | A rating |
| Oritain UK Limited | London | A rating |
| ORIX Corporation UK Limited | London | A rating |
| Orlen LNG Trading Limited | London | A rating |
| ORMAZABAL UK LIMITED | St. Helens | A rating |
| ORMONDE HOUSE CAPITAL LTD | LONDON | A rating |
| Orona Ltd | Sunbury-on-Thames | A rating |
| ORRICK HERRINGTON & SUTCLIFFE (UK) LLP | LONDON | A rating |
| Orsted Power (UK) Limited | London | A rating |
| ORTEC FINANCE LTD | LONDON | A rating |
| Ortec UK Ltd | Birmingham | A rating |
| Ortho-Clinical Diagnostics | Pencoed,Bridgend | A rating |
| ORTHOHOUSE SOLUTIONS LTD | London | A rating |
| Orveon Global Ltd | London | A rating |
| Osaka Gas UK, Ltd | London | A rating |
| Osborne Clarke Services | Bristol | A rating |
| Osborne Partners Limited | London | A rating |
| OSG UK Limited | Basildon | A rating |
| Oshima Shipbuilding Europe Limited | London | A rating |
| OSI FOOD SOLUTIONS UK LIMITED | SCUNTHORPE | A rating |
| OSL UK PVT Limited | London | A rating |
| OSMOS SISTEMAS ELECTRICOS UK LTD | London | A rating |
| Osmosis Buyer Limited (UK) | Dereham | A rating |
| Osmosys Software Solutions UK Limited | London, | A rating |
| OSRL (Oil Spill Response Limited) | Southampton | A rating |
| OTC Europe LLP | London | A rating |
| Oticon Ltd | Hamilton | A rating |
| Otis Limited | London | A rating |
| OTOVO LIMITED | LONDON | A rating |
| OTRIUM UK LIMITED | Manchester | A rating |
| Otsuka Pharmaceutical Europe Ltd | Windsor | A rating |
| Otto Bock Healthcare PLC | Egham | A rating |
| Oud Milano UK Ltd t/a Abdul Samad Alqurashi and Oud Milano | Hitchin | A rating |
| Outback Imaging UK Limited | London | A rating |
| OUTBRAIN UK LTD | London | A rating |
| Outreach Corporation UK Limited | London | A rating |
| Outright Games Limited | Lee-on-the-Solent | A rating |
| OutSystems Limited | London | A rating |
| Ove Arup and Partners International Ltd | London | A rating |
| Oversea-Chinese Banking Corporation Ltd | London | A rating |
| Overwatch Mission Critical EMEA Limited | London | A rating |
| OVH Ltd | London | A rating |
| OVIVO UK Ltd | Wolverhampton | A rating |
| OVO Group LTD | Bristol | A rating |
| OWENS CORNING VEIL UK LTD | LIVERSEDGE | A rating |
| Owkin UK Ltd | London | A rating |
| Owl Ventures Management UK Limited | London | A rating |
| Ox Mountain Limited | Oxford | A rating |
| Oxfam GB | Oxford | A rating |
| Oxford Analytica | Oxford | A rating |
| Oxford BioMedica (UK) Ltd | Oxford | A rating |
| Oxford BioTherapeutics Ltd | Oxford | A rating |
| Oxford Gene Technology IP Limited | Kidlington | A rating |
| Oxford Genetics Limited | London | A rating |
| Oxford Genetics Ltd | Oxford | A rating |
| Oxford Immunotec Limited T/A Revvity | Abingdon | A rating |
| Oxford Instruments Nanotechnology Tools Limited | Abingdon | A rating |
| Oxford Ionics Limited | Kidlington | A rating |
| Oxford Policy Management Limited | Oxford | A rating |
| Oxford Properties Management (UK) Limited | London | A rating |
| Oxford University Press | Oxford | A rating |
| Oxoid Limited | Basingstoke | A rating |
| OYO Technology and Hospitality (UK) Ltd | London | A rating |
| Oyster Yachts Limited | Southampton | A rating |
| P & S MEDICAL EDUCATION LIMITED | Boldon Colliery | A rating |
| P.I. WORKS UK LTD | Marlow | A rating |
| P.R.Marriott Drilling Ltd | Chesterfield | A rating |
| P/E Investments UK Associates Ltd. | London | A rating |
| P&O Steam Navigation Company | London | A rating |
| P&P Group Holdings Limited | London | A rating |
| PA Holdings Limited | Melbourn | A rating |
| Pacadar UK Limited | Chatham | A rating |
| Pacific Basin Shipping (UK) Limited | London | A rating |
| Pacific Biosciences UK Limited | West Wickham | A rating |
| Pacific Consulting Group UK Limited | London | A rating |
| Pacific International Recruitment Limited | Norwich | A rating |
| Pacific Investments Management Limited | London | A rating |
| Pacific Life Re Services Limited | London | A rating |
| Pacific Prime Consultants Limited | London | A rating |
| PACSHealth Ltd | London | A rating |
| Paddlers UK Ltd. | London | A rating |
| Padero Solaer Ltd t/a PS Renewables | Hare Hatch | A rating |
| Page Up People Ltd | Derby | A rating |
| PagerDuty Limited | London | A rating |
| PAI Partners (UK) Limited | London | A rating |
| Paige Europe Limited | London | A rating |
| Pakistan International Airlines | Brentford | A rating |
| Palantir Technologies UK Limited | London | A rating |
| Palantir UK Limited | London | A rating |
| Palisade Real Assets UK Ltd | Cardiff | A rating |
| Pall Europe Ltd | Portsmouth | A rating |
| Palladium International Limited | London | A rating |
| Palliser Capital (UK) Ltd | London | A rating |
| Palmer Automotive Limited | Towester | A rating |
| PALO ALTO NETWORKS (UK) LIMITED | London | A rating |
| Palram Europe Limited | Doncaster | A rating |
| Pamargan Products Ltd | Newtown | A rating |
| Pan Pacific London Hotel Ltd | London | A rating |
| Panasonic Avionics Corporation | Langley | A rating |
| Panasonic Business Support Europe GmbH, UK Branch | Bracknell | A rating |
| Panasonic Europe B.V., UK Branch | Bracknell | A rating |
| Panasonic Manufacturing U.K. Ltd | Cardiff | A rating |
| Panattoni UK Developments Limited | London | A rating |
| Pandora Jewellery UK Ltd | London | A rating |
| Panesar Foods Limited | Tipton | A rating |
| Pangaea Data Ltd | London | A rating |
| Pangea Group UK Limited | London | A rating |
| Panmure Liberum Limited | London | A rating |
| PANORAMA YACHT LONDON LIMITED | HIGH WYCOMBE | A rating |
| Panoramah (UK) Limited | London | A rating |
| Panterra Global Ltd | London | A rating |
| Pantheon Platform UK Limited | London | A rating |
| Pantheon Ventures (UK) LLP | London | A rating |
| Papa John's (GB) Limited | Milton Keynes | A rating |
| Paperchase Accountancy Limited | Croydon | A rating |
| PAPREC UK LIMITED | Sheffield | A rating |
| Paradigm Flow Technologies Limited | Aberdeen | A rating |
| Parallel Wireless UK limited | Bristol | A rating |
| Parametric Technology (UK) Limited | Bristol | A rating |
| PARAMOUNT GLOBAL PROPERTY SERVICES LIMITED | London | A rating |
| Paramount Pictures International Limited | London | A rating |
| ParentPay Limited | Somerset | A rating |
| PAREXEL International Limited | UXBRIDGE | A rating |
| Parfums Christian Dior (UK) Ltd | Surrey | A rating |
| Parity Financial Limited t/a Parfin | London | A rating |
| Park Corporation UK Branch | London | A rating |
| Park Energy Law UK Ltd | London | A rating |
| Park Square Capital LLP | London | A rating |
| Parker Hannifin Manufacturing Limited | Hemel Hempstead | A rating |
| Parsable Inc | Malmesbury | A rating |
| Parsons Group International limited | London | A rating |
| Parsyl Limited | London | A rating |
| Partly UK Limited | London | A rating |
| Partner Reinsurance Europe SE, UK Branch | London | A rating |
| Partners Capital LLP | London | A rating |
| Partners Group (UK) Ltd. | London | A rating |
| Partners in Performance UK Limited | London | A rating |
| Parvalux Electric Motors Limited | Poole | A rating |
| Passion F and B Limited | London | A rating |
| Pasta Evangelists Ltd | London | A rating |
| Patchbay Media Limited | London | A rating |
| PATEK PHILIPPE SALON LIMITED | London | A rating |
| PATEK PHILIPPE UK LIMITED | Beaconsfield | A rating |
| Paterson & Cooke (UK) Ltd. | Cornwall | A rating |
| Patheon UK Ltd | Swindon | A rating |
| Pathlock UK Ltd | Leatherhead | A rating |
| Pathway Capital Management (UK) Limited | London | A rating |
| Pathways Alliance Ltd | Durham | A rating |
| Patria Investments UK Ltd | London | A rating |
| Patria Private Equity (Europe) Limited | Edinburgh | A rating |
| Patrizia UK Limited | London | A rating |
| PatSnap (UK) Ltd | London | A rating |
| Pattern Trading Ltd | London | A rating |
| Paul Hartmann Limited | Heywood | A rating |
| Paul Hastings (Europe) LLP | London | A rating |
| Paul Mason Consulting Ltd | Abingdon | A rating |
| Paul Mellon Centre for Studies in British Art | London | A rating |
| PAUL NULTY LIGHTING DESIGN LTD | LONDON | A rating |
| Paul, Weiss, Rifkind, Wharton & Garrison LLP, a Delaware limited liability partnership. | London | A rating |
| Pauls Malt Limited | Bury St Edmunds | A rating |
| Pax8 UK Limited | Bristol | A rating |
| Paxos Technology Limited | London | A rating |
| PAY CHECK LIMITED | LONDON | A rating |
| Payden & Rygel Global Ltd | London | A rating |
| Payoma Limited | London | A rating |
| PAYONEER (UK) LIMITED | LONDON | A rating |
| PayPal Ltd | London | A rating |
| PayPal UK Ltd | London | A rating |
| PayPoint plc | Welwyn Garden City | A rating |
| PayProp Holdings Limited | London | A rating |
| PB Leiner (PB Gelatins UK Ltd) | Pontypridd | A rating |
| PBP SERVICES | Fraserburgh | A rating |
| PBS870 LIVE SSW SPONSOR | PBS870 LIVE SSW SPONSOR | A rating |
| PBTS Europe Limited | London | A rating |
| PCC UK Global Holdings Limited | Leicester | A rating |