| Mignag Limited | Wholesale & retail | 2026 |
| Mike Harding Lighting Solutions Ltd. | Construction | 2006 |
| Mike Moores Electrical and Plumbing Services Limited | Professional & scientific | 2004 |
| Mike Rickman Roofing Ltd | Construction | 2007 |
| Mileridge Limited | Professional & scientific | 2005 |
| Mill House Gardens (Denmead) Limited | Households | 2006 |
| Millbank Investments Limited | Financial services | 2007 |
| Millerchip Software Limited | Information & communication | 2005 |
| Milton Glass Limited | Professional & scientific | 2000 |
| Minden Engineering Limited | Manufacturing | 2006 |
| Mindfizz Limited | Information & communication | 1999 |
| Minelone Limited | Construction | 1988 |
| Miouyas Limited | Wholesale & retail | 2026 |
| Mira 3 Limited | Arts & recreation | 2000 |
| Miriam Zikry Healthcare Ltd | Health & social care | 2023 |
| Mitchellwood Travel Limited | Administrative & support | 1999 |
| Mitutoyo (U.K.) Limited | Manufacturing | 1979 |
| MJC Bookkeeping Limited | Professional & scientific | 2002 |
| MJD Roofing Specialists Limited | Construction | 2003 |
| ML Site Services Limited | Construction | 2008 |
| Moda Resourcing Limited | Administrative & support | 2007 |
| Monkton Park Golf Limited | Arts & recreation | 2004 |
| Montgomery Moore Limited | Professional & scientific | 2004 |
| MOO MOO Holdings Limited | Financial services | 2022 |
| Moorhaven Residents Association Limited | Households | 1995 |
| Moorhen Trout Fishery Ltd | Agriculture & fishing | 2007 |
| Moortown House Management Company Limited | Households | 1991 |
| Moreed & Team Ltd | Administrative & support | 2022 |
| Morgan A.I. Development Solutions Limited | Information & communication | 2025 |
| Motest U.K. Limited | Wholesale & retail | 1998 |
| Moto Exchange Ltd | Wholesale & retail | 2005 |
| Motofax International Limited | Wholesale & retail | 2000 |
| Motor Marketing Group Limited | Professional & scientific | 2024 |
| Motor Marketing Ventures LLP | | 2024 |
| Motorspeed (Portsmouth) Limited | Wholesale & retail | 2002 |
| MR Stainless Ltd | Manufacturing | 2008 |
| MSC Steam Cleaning Limited | Administrative & support | 2004 |
| MSL Computers Limited | Information & communication | 2001 |
| MSQ Developments Ltd | Construction | 2004 |
| MTC Water Jetting Limited | | 1977 |
| Mulder & Rijke Limited | Extraterritorial | 1986 |
| Mullan Racing Ltd | Administrative & support | 2024 |
| Multi-Track Dialogue and Peace Support Group | Professional & scientific | 2024 |
| Multilast Analysis Limited | Information & communication | 1988 |
| Multimedia Entertainments Group Limited | Professional & scientific | 2006 |
| Mumford Davies Limited | Professional & scientific | 2001 |
| Murray West Associates Limited | Financial services | 2003 |
| Murraylectrics Ltd | Manufacturing | 2007 |
| Muskoka Trading Limited | Wholesale & retail | 2005 |
| Mustrade Limited | Wholesale & retail | 2008 |
| MVB Body Repair Centre Limited | Administrative & support | 2005 |
| My Music Shop Ltd | Extraterritorial | 2006 |
| Mytchett Holiday Homes Limited | Financial services | 1996 |
| N & T Carpentry & Builders Limited | Construction | 2003 |
| N C House Limited | Hospitality | 2018 |
| N Ferre Limited | Wholesale & retail | 2002 |
| N.C. LA Engineering Limited | Wholesale & retail | 1986 |
| N.Day Heating & Plumbing Ltd. | Energy | 2003 |
| N.J.Buckingham Limited | Construction | 1963 |
| Namaste Johney Gurkha Limited | Hospitality | 2015 |
| NAP Construction Ltd | Administrative & support | 2003 |
| Nash Construction Limited | | 1986 |
| Nashblend Limited | Construction | 1993 |
| Nashline Holdings Limited | Professional & scientific | 1999 |
| National Agora' Ukeig | | 2007 |
| National Intruder Alarms Limited | Administrative & support | 2002 |
| Natures Flow Limited | Professional & scientific | 2004 |
| Naughty Zombie Limited | Information & communication | 2006 |
| NB Dining Ltd | Hospitality | 2019 |
| NBC Installations Ltd | Construction | 2006 |
| Neal Engineering Services Limited | Professional & scientific | 2006 |
| NEC GB Ltd | Professional & scientific | 2005 |
| Neil Davies Environmental Services Limited | Construction | 2007 |
| Neoptera Ltd | Professional & scientific | 2001 |
| Netley Garage Limited | Wholesale & retail | 2007 |
| Nettmore Limited | Information & communication | 2006 |
| New Forest Carriers Limited | Transport & logistics | 2007 |
| New Forest Ceilings Limited | Construction | 1986 |
| New Forest Disability Information Service | Health & social care | 2004 |
| New Forest Golf Club Limited | Arts & recreation | 2004 |
| New Forest Museum Trading Limited | Wholesale & retail | 1998 |
| New Lane Investments Limited | Administrative & support | 2004 |
| New Milton Motor Services Limited | Wholesale & retail | 1997 |
| New Milton Sand and Ballast Limited | Mining & quarrying | 1957 |
| New Park Events Limited | Hospitality | 2004 |
| New Yasir ALI Security Limited | Extraterritorial | 2019 |
| Newbery Consultants Limited | Professional & scientific | 1997 |
| Newsforce Promotions Limited | Wholesale & retail | 1989 |
| Newton Valence Farms Limited | Agriculture & fishing | 1982 |
| Next Level Communications Limited | Information & communication | 1998 |
| Neyland Yacht Haven Limited | Arts & recreation | 1992 |
| Nightingale Care Limited | Health & social care | 1986 |
| Nissit Ltd | Information & communication | 1997 |
| NLP Mortgage Solutions Limited | Financial services | 2025 |
| NME Project Management Ltd | Professional & scientific | 2004 |
| NMK Associates Ltd | Professional & scientific | 2004 |
| Nolanheath Limited | Information & communication | 1984 |
| Nomax Limited | Manufacturing | 1987 |
| Norman Court (Farnham) Residents Management Limited | Households | 1987 |
| Northern Technical & Chemical Services Limited | Professional & scientific | 2007 |