| MTorres UK Limited | Saltney | A rating |
| MTR Corporation (Crossrail) Limited | London | A rating |
| MTR Corporation Limited | London | A rating |
| MTS Systems Ltd | Leeds | A rating |
| MTV Networks Europe | London | A rating |
| Mu Sigma Limited | North Harrow | A rating |
| MUBI UK Limited | London | A rating |
| Much. Consulting Ltd | Manchester | A rating |
| Muehlhan Wind Service A/S | Hull | A rating |
| Mueller International Holdings Limited | Southampton | A rating |
| MUFG Bank, Ltd. | London | A rating |
| MUFG CORPORATE MARKETS (UK) LIMITED | Leeds | A rating |
| MUFG FUND SERVICES (UK) LIMITED | London | A rating |
| Mugen Euro Co Ltd | Milton Keynes | A rating |
| MUJI Europe Limited | London | A rating |
| MullenLowe Group Limited | London | A rating |
| Muller UK & Ireland Group LLP T/A Muller Milk & Ingredients | Market Drayton | A rating |
| Multi Installations Limited | Burgess Hill | A rating |
| Multi Packaging Solutions UK Limited | Nottingham | A rating |
| Multi-Color Cwmbran UK Limited | Cwmbran | A rating |
| Multimodal Logistics Ltd | Felixstowe | A rating |
| Multiplai Limited | Cramlington | A rating |
| Multiplex Construction Europe Limited | London | A rating |
| MUN (UK) LTD | Old Harlow | A rating |
| Mundipharma International Limited | Cambridge | A rating |
| Mundipharma Medical Company Ltd | Cambridge | A rating |
| Munich Re UK Services Limited | London | A rating |
| Munster Joinery (U.K) Limited | Wellesbourne | A rating |
| Murata Power Solutions | Milton Keynes | A rating |
| Murex UK Limited | London | A rating |
| Murphy Geospatial UK Ltd | Watford | A rating |
| Murrelektronik Ltd | Manchester | A rating |
| Murzuq Oil Services Limited | London | A rating |
| MUSARUBRA UK SUBSIDIARY 3 LTD | Slough | A rating |
| Musco Lighting Europe LTD | Bolton | A rating |
| Muslim Aid | London | A rating |
| Muslim Hands | Nottingham | A rating |
| Must Investment UK | New Malden | A rating |
| Mustang Engineering Limited | Woking | A rating |
| MUTARES UK LTD | Birmingham | A rating |
| Muthu Clumber Park Hotel & Spa | Worksop | A rating |
| Mutti UK Limited | London | A rating |
| Mux UK Limited | London | A rating |
| Muzinich & Co. Limited | London | A rating |
| MVCI Europe Limited | London | A rating |
| MVV Environment Ltd | Plymouth | A rating |
| My Digital Accounts Limited | Cheadle Hulme | A rating |
| mycitydeal Limited t/a Groupon | London | A rating |
| Mycom (UK) Ltd | London | A rating |
| MYDEEDS LTD | LONDON | A rating |
| MyJoVE Europe, Inc | London | A rating |
| Mylan Pharma UK Limited | Sandwich | A rating |
| MYPINPAD Ltd | Cardiff | A rating |
| Myunidays Limited | Nottingham | A rating |
| N Consulting Ltd | London | A rating |
| N-Sea UK Ltd | Chichester | A rating |
| N.M.Rothschild & Sons Limited | London | A rating |
| Nacional Financiera | London | A rating |
| Nadara Limited | Edinburgh | A rating |
| NAFT TRADING & TECHNOLOGY CO LIMITED | LONDON | A rating |
| Nagarro Software Ltd | London | A rating |
| Nagashima Ohno & Tsunematsu UK Limited | London | A rating |
| NAGRA Media UK Limited | Cwmbran | A rating |
| Naigai Nitto Logistics ( Europe) Ltd | Birmingham | A rating |
| Naim Audio Ltd | Salisbury | A rating |
| Nakano Asset Global Ltd | London | A rating |
| NALA PAYMENTS LIMITED | London | A rating |
| Nala Renewables UK | Paddington | A rating |
| Namura Shipbuilding Co Ltd | London | A rating |
| Nando's Ltd | London | A rating |
| Nanoavionics UK Limited | Basingstoke | A rating |
| Nanograb Limited | London | A rating |
| NanoString Technologies Europe Limited | Bristol | A rating |
| NAPA Centre UK Limited | London | A rating |
| Napier Park Global Capital Ltd | London | A rating |
| Narvar UK Limited | London | A rating |
| Nasdaq Limited | London | A rating |
| NashTech Limited | London | A rating |
| NASUNI UK LITD | OXFORDSHIRE | A rating |
| Natara Global | Hartlepool | A rating |
| National Australia Bank Ltd | London | A rating |
| National Bank Financial Inc. | London | A rating |
| National Bank of Canada | London | A rating |
| NATIONAL BANK OF EGYPT (UK) LIMITED | LONDON | A rating |
| National Bank of Kuwait International PLC | London | A rating |
| National Express Limited | Birmingham | A rating |
| National Grid Electricity Distribution (South West) plc | Bristol | A rating |
| National Grid plc | Warwick | A rating |
| National Instruments Corporation (UK) Ltd | Reading | A rating |
| National Magazine Company Limited | London | A rating |
| National Oilwell Varco UK Limited | Aberdeen | A rating |
| NATIONAL VETERINARY SERVICES LIMITED | Stoke-on-Trent | A rating |
| Nationwide Holdings Limited | London | A rating |
| Native Design Limited | London | A rating |
| Native Instruments UK Ltd | Birmingham | A rating |
| Natixis Investment Managers UK LImited | London | A rating |
| Natixis Londres | London | A rating |
| Natrio UK Ltd | London | A rating |
| NATS Limited | Fareham | A rating |
| Natural Herb Solution UK Ltd. | New Malden | A rating |
| NaturalMotion Limited | London | A rating |
| NatureMetrics Ltd | Guildford | A rating |
| NATURES MENU LIMITED | SNETTERTON | A rating |
| NatWest Group PLC | Edinburgh | A rating |
| NaudaPay Limited | London | A rating |
| NautaDutilh | London | A rating |
| Nautic Steels Ltd | Tamworth | A rating |
| Navan Labs UK Limited | London | A rating |
| Navantia UK Ltd | London | A rating |
| Navico UK Limited | Southampton | A rating |
| NAVIEN UK LTD | Guildford | A rating |
| Navig8 Europe Ltd | London | A rating |
| Navigator Gas | London | A rating |
| NaviNet Ltd | Belfast | A rating |
| NAVIS SOFTWARE UK LIMITED | LONDON | A rating |
| Navitas Life Sciences Limited | Portsmouth | A rating |
| Navitas Petroleum Development and Production Ltd | London | A rating |
| Navitas UK Holdings Limited | Abingdon | A rating |
| NBA UK Ltd | London | A rating |
| NBBJ Limited | London | A rating |
| NBCUniversal International Limited | London | A rating |
| NBI Analytics UK Limited | London | A rating |
| NCC Group plc | Manchester | A rating |
| NCH (UK) Limited | Bilston | A rating |
| nCino Global Limited | London | A rating |
| NCR Limited | London | A rating |
| NCsoft Europe Limited | London | A rating |
| NCTM LLP | London | A rating |
| NDK Europe Limited | Kingston-upon-Thames | A rating |
| NDY Consulting Ltd | London | A rating |
| Near East Foundation UK | London | A rating |
| NearForm UK Limited | London | A rating |
| NEC Europe Ltd | Uxbridge | A rating |
| NEC Telecom MODUS, Ltd | Leatherhead | A rating |
| Nectar Sleep Ltd | Milton Keynes | A rating |
| Nedbank Ltd | London | A rating |
| NEEDaFIXER Limited | London | A rating |
| Neelikon Specialities Europe Ltd | Leicestershire | A rating |
| Negociants UK Limited | Harpenden | A rating |
| NeilMed Ltd | Croydon | A rating |
| Neilsoft Limited | London | A rating |
| Neko Health UK Limited | London | A rating |
| NEMESIS LABORATORIES UK LTD | London | A rating |
| Nendrasys Technologies UK Limited | Milton Keynes | A rating |
| NEO NEXT+ ENERGY E&P UK Limited | London | A rating |
| NEO4J UK LIMITED | London | A rating |
| Neogen Europe Ltd | Ayr | A rating |
| Neosalpha Technologies Limited | Maidenhead | A rating |
| Neoss Limited | Harrogate | A rating |
| Neota Logic Limited | London | A rating |
| Neovia Logistics Services (U.K.) Limited | Desford | A rating |
| NEP UK Limited | Bracknell | A rating |
| NEPA UK LTD | London | A rating |
| Nephila Management Services Ltd | London | A rating |
| NERA UK LIMITED | London | A rating |
| NerdWallet Ltd. | Norwich | A rating |
| NERO HOLDINGS LIMITED | London | A rating |
| NES Group Limited | Altrincham | A rating |
| NES Holdings (UK) Limited | Norwich | A rating |
| NESS GLOBAL SERVICES LIMITED | West Wickham | A rating |
| Nest Digital Limited | London | A rating |
| Nesta | London | A rating |
| Nestec York Ltd | York | A rating |
| Nestle UK Limited | Crawley | A rating |
| NET-A-PORTER GROUP Ltd | London | A rating |
| NetApp UK | Windsor | A rating |
| Netbase Global Limited | Bristol | A rating |
| Netcompany UK Limited | London | A rating |
| NetCracker Technology EMEA Ltd | Histon | A rating |
| NetDocuments Limited | Winnersh | A rating |
| NETEX (UK) LIMITED | Weybridge | A rating |
| Netflix Services UK Limited | London | A rating |
| NETFLIX STUDIOS UK LIMITED | LONDON | A rating |
| NetJets Management Limited | London | A rating |
| Netlify UK Limited | London | A rating |
| NETLIGHT CONSULTING LIMITED | SLOUGH | A rating |
| Netmore IOT Solutions Ltd | Coach Close, Worksop | A rating |
| NETS DENMARK A/S | London | A rating |
| NETS International Limited | Redhill | A rating |
| Netskope UK Ltd | London | A rating |
| Netsol Technologies Europe Limited | Horsham | A rating |
| Network Access Associates Limited | London | A rating |
| Netwrix (UK) Ltd | Otley | A rating |
| Neuberger Berman Europe Limited | London | A rating |
| Neuberger Berman Europe Ltd | London | A rating |
| Neuro Tour Physiotherapy, Limited | London | A rating |
| Neurone Services Limited | London | A rating |
| New Balance Athletic Shoes UK Limited | Warrington | A rating |
| New England Seafood International Ltd | Chessington | A rating |
| New Enterprise Associates (UK), Ltd. | London | A rating |
| NEW ERA CAP COMPANY LIMITED | MILTON KEYNES | A rating |
| New Fame Foods Limited T/A Saravanaa Bhavan | Harrow | A rating |
| New Lobster Ltd | London | A rating |
| New Oriental Vision Overseas Consulting (U.K.) Limited | London | A rating |
| New Planet Farms Limited | London | A rating |
| New Relic UK Limited | London | A rating |
| New Science Ventures Management Limited | London | A rating |
| New York Times Limited | LONDON | A rating |
| Newcastle University | Newcastle Upon Tyne | A rating |
| newcleo Generation (UK) Ltd | London | A rating |