| Money Saver Stores Ltd | Extraterritorial | 2002 |
| Monument Fire Detection Systems Limited | Administrative & support | 2002 |
| Mood Commercial Limited | Professional & scientific | 2006 |
| Moor Hall Hotel Limited | Hospitality | 1961 |
| Moorcroft Holdings Limited | Professional & scientific | 1992 |
| Mordene Designs Limited | Administrative & support | 1986 |
| More-Heli Limited | Transport & logistics | 2014 |
| Morgan Degville Associates Limited | Professional & scientific | 2006 |
| Mosmab Limited | Wholesale & retail | 2016 |
| MOT Clinic Limited | Wholesale & retail | 2007 |
| Moto-Tech Auto Services Limited | Wholesale & retail | 2002 |
| Motobattery Ltd | Manufacturing | 2023 |
| Mount Zion Christian Community Church | Other services | 2007 |
| Mountview Consultants Limited | Professional & scientific | 2000 |
| Mowlem Northern Limited | Extraterritorial | 1970 |
| Mowlem Shelfco 2 Limited | Extraterritorial | 1970 |
| Mpofu Social Work Services Limited | Health & social care | 2014 |
| MQ Freehold Ltd | Real estate | 2024 |
| Msate Holdings Group Ltd | Extraterritorial | 2021 |
| MSC Consultancy Limited | Information & communication | 2006 |
| MTA Investments Limited | Hospitality | 1999 |
| Mucklow Hill Interiors Limited | Manufacturing | 2004 |
| Mucky Pups Day Nursery Limited | Education | 2000 |
| Mueller Europe Limited | Manufacturing | 1997 |
| Mukesh Aggarwal Limited | Professional & scientific | 2003 |
| Multi Commerce Ltd | Other services | 2023 |
| Multi-Stroke Limited | Manufacturing | 1966 |
| Multiterm Limited | Manufacturing | 1985 |
| Musa Shahid Ltd | Wholesale & retail | 2024 |
| Mushtaq's Limited | Manufacturing | 1999 |
| Musicjuice Limited | Administrative & support | 2001 |
| Mwic QA Solutions Ltd | Information & communication | 2006 |
| My Floor Limited | Extraterritorial | 2007 |
| Mysafetyhub Limited | Wholesale & retail | 2008 |
| N K Kreations Ltd | Arts & recreation | 2007 |
| N. Hingley (Coachtrimmers) Limited | Wholesale & retail | 1978 |
| N. Pugh Systems Software Limited | Information & communication | 1997 |
| N. Walsh Plant Services Limited | Manufacturing | 2000 |
| N.D. JIG and Gauge Company Limited | Manufacturing | 1948 |
| N.S.G. Capital Limited | Real estate | 1994 |
| N.Smith & Company Limited | Manufacturing | 1923 |
| NA Consulting Limited | Professional & scientific | 2023 |
| Naqvix Ltd | Information & communication | 2025 |
| Nathan IT Management Limited | Other services | 2007 |
| Nathan Rose Music Tuition Limited | Education | 2004 |
| Nationwide Inspection Services Limited | Professional & scientific | 2003 |
| Nationwide Machinery U.K Limited | Administrative & support | 1998 |
| Natural Stone Supplies Limited | Wholesale & retail | 2007 |
| Navhim Properties Ltd | Real estate | 2024 |
| Navro Limited | Administrative & support | 2019 |
| Navs Blinds Central Limited | Manufacturing | 2023 |
| Navsarka Ltd | Wholesale & retail | 2007 |
| Nayyar Consulting Limited | Information & communication | 2007 |
| Nazir Associates Ltd | Professional & scientific | 2000 |
| Nazrana Kitchen Ltd | Wholesale & retail | 2022 |
| NCK Property Ltd | Real estate | 2025 |
| Neil Company Properties Limited | Real estate | 2007 |
| Neil Hesson & Co Ltd | Professional & scientific | 2003 |
| Neoacoustic UK Limited | Manufacturing | 2023 |
| New Canaan Investments Limited | Professional & scientific | 1999 |
| New Energy Investment Group Limited | Administrative & support | 2005 |
| New Financial Options Limited | Financial services | 2007 |
| New Heights - Warren Farm Community Project | Other services | 2006 |
| New Medina Superstore Limited | Wholesale & retail | 2004 |
| New Yuefeng Trading Co., Ltd | Wholesale & retail | 2023 |
| Newbold Court Management Limited | Households | 1982 |
| Newbridge Technical Services Limited | Information & communication | 2002 |
| Newby and SON (Ironfounders) Limited | Manufacturing | 1985 |
| Newby Holdings Limited | Professional & scientific | 1938 |
| Newcrest Tools Limited | Real estate | 1985 |
| Newey Installations Limited | Manufacturing | 2004 |
| Newman James Limited | Professional & scientific | 2007 |
| Newman T.Cole Limited | Real estate | 1988 |
| Newport Galvanizers Limited | Manufacturing | 1965 |
| Newstart Services Limited | Hospitality | 2001 |
| Next Day Delivery Ltd | Transport & logistics | 2018 |
| Nextworkingday Ltd | Professional & scientific | 2001 |
| NI Technologies Limited | Information & communication | 2003 |
| Nick Lawrence Consultancy Services Limited | Professional & scientific | 2000 |
| Nickolls & Perks Limited | Wholesale & retail | 1963 |
| Nicolette Limited | Real estate | 1956 |
| Nimag Precision Engineering Limited | Manufacturing | 1983 |
| Ningbo Transco Belt Co., Ltd | Manufacturing | 2023 |
| Nishkam Security Limited | Administrative & support | 2006 |
| NK Stores Limited | Wholesale & retail | 2021 |
| NLS Consulting Limited | Information & communication | 1999 |
| Noble & Llewellyn (Alum Rock) Limited | Other services | 1973 |
| Norfolk Automation and Control Ltd | Extraterritorial | 2020 |
| Norman C Sands Limited | Professional & scientific | 2002 |
| North Birmingham Bridge Club Limited | Arts & recreation | 1998 |
| North East Galvanizing Limited | Extraterritorial | 1980 |
| Northleigh Limited | Information & communication | 2007 |
| Norton Building Consultancy Limited | Manufacturing | 1999 |
| Norton OFF License Ltd | Wholesale & retail | 2013 |
| Norway Aite Farmer Group Co., Ltd | Mining & quarrying | 2023 |
| Norway Gelite Chymistry Enginnering Ltd | Extraterritorial | 2020 |
| Norway Yaya International Co., Ltd | Wholesale & retail | 2024 |
| Noteworthy Productions Limited | Arts & recreation | 2000 |
| Nova Training Limited | Education | 1992 |
| Novare Holdings Limited | Financial services | 2025 |