| Monty Management Limited | Arts & recreation | 2000 |
| Moores Independent Limited | Professional & scientific | 2011 |
| Moriconium Quay Freehold Limited | Households | 2007 |
| Moriconium Quay Management Company Limited | Households | 1990 |
| Motor Show Consultants Ltd | Administrative & support | 2025 |
| Motor Shows Ltd | Administrative & support | 2025 |
| Mountsan Property Co Limited | | 1971 |
| MSH Aviation Limited | Manufacturing | 2014 |
| MTS Property Holdings Limited | Real estate | 2023 |
| Muddy Boots Fordingbridge Limited | Education | 2020 |
| Mulberry House Management (Fordingbridge) Limited | Households | 1985 |
| Multistory Films Limited | Information & communication | 2010 |
| Music Makers Events Ltd | Other services | 2011 |
| Musical Spares Limited | Extraterritorial | 2014 |
| MW Connections Limited | Financial services | 2012 |
| My Nesessity Ltd | Wholesale & retail | 2021 |
| My Recruit App Limited | Administrative & support | 2016 |
| MYK Investments Ltd | Financial services | 2019 |
| Mymonthend Limited | Information & communication | 2019 |
| Myriad Retail Limited | Wholesale & retail | 2022 |
| Napier Management Services Limited | Real estate | 1994 |
| Natural Green Energy Ltd | Professional & scientific | 2014 |
| Nesta Groundworks Ltd | Construction | 2026 |
| Netheravon Residents Company Limited | Households | 1997 |
| Networktv Limited | Wholesale & retail | 2020 |
| New Dimension (Builders) Limited | Construction | 2006 |
| New Dimension Plumbing and Electrical Limited | Construction | 2014 |
| New Directions Europe Ltd | Manufacturing | 2012 |
| New Forest & Waters Edge Lettings Limited | Real estate | 2013 |
| New Forest Building Co. Ltd | Construction | 2023 |
| New Forest Building Contractors Ltd | Financial services | 2025 |
| New Forest Burners Ltd | Construction | 2024 |
| New Forest Direct Cremations Ltd | Other services | 2026 |
| New Forest Exterior Cleaning Ltd | Administrative & support | 2023 |
| New Forest Firewood Co Ltd | Wholesale & retail | 2021 |
| New Forest Flower Fairies Limited | Wholesale & retail | 2025 |
| New Forest Harbridge Ltd | Hospitality | 2024 |
| New Forest Holidays Limited | Hospitality | 2025 |
| New Forest Homewares Ltd | Wholesale & retail | 2021 |
| New Forest Interior Designs Ltd | Wholesale & retail | 2019 |
| New Forest LOG Supplies Ltd | Wholesale & retail | 2025 |
| New Forest SAW Company Limited | Manufacturing | 2016 |
| New Forest Solutions Ltd | Water & waste | 2010 |
| New Forest Tree & Garden Services Ltd | Administrative & support | 2018 |
| New ME Psychology Ltd | Health & social care | 2020 |
| New Pastures Butchers Ltd | Wholesale & retail | 2018 |
| Newbourne Farm Composting Limited | Water & waste | 2013 |
| Newtown Farm LLP | | 2013 |
| Next Level Consulting Associates Limited | Professional & scientific | 2017 |
| Next Step IT Limited | Information & communication | 2005 |
| Nicholson Andrew Ltd | Financial services | 2022 |
| Nine Brains Limited | Health & social care | 2023 |
| NO Fault Divorce Ltd | Information & communication | 2022 |
| Nous Wellbeing Limited | Health & social care | 2026 |
| Novominster Properties Limited | Construction | 1990 |
| Novoscope IP Limited | Financial services | 2013 |
| Nuvocom Ltd | Wholesale & retail | 2021 |
| NWH Advice Limited | Financial services | 2023 |
| O2 Shift Ltd | Health & social care | 2025 |
| Oakley Bowers Limited | Administrative & support | 2024 |
| Oakridge CT Ltd | Professional & scientific | 2024 |
| Oakwood Trading Limited | Information & communication | 2009 |
| Oiltec Heating Ltd | Construction | 2017 |
| Old Enterprise Limited | Administrative & support | 2002 |
| Old Forge (Linford Road) Management Company Limited | Households | 2009 |
| Old Pottery Property Management Ltd | Real estate | 2026 |
| Oliver Cutts Agriculture Ltd | Agriculture & fishing | 2015 |
| Oliver Cutts Estates Limited | Hospitality | 2008 |
| Oliver Cutts Ltd | Administrative & support | 2001 |
| One L and a Y Limited | Information & communication | 2014 |
| Onecompany Performing Arts Ltd | Arts & recreation | 2025 |
| Opening Young Minds Ltd | Education | 2020 |
| Optimum Tax and Accounting Limited | Professional & scientific | 2015 |
| Optimum Tax Solutions Limited | Professional & scientific | 2004 |
| Orleans Investments Limited | Real estate | 1990 |
| Oryx HR Limited | Administrative & support | 2019 |
| Osprey Paintworks Ltd | Construction | 2025 |
| Outplacement Ltd | Education | 2024 |
| Oven Ready Homes Ltd | Construction | 2017 |
| Overseen Limited | Construction | 2024 |
| Oyster Quay (Hamble) Limited | Households | 2004 |
| P. Lucas Builder Ltd | Administrative & support | 2017 |
| Pacific Close Estates Limited | Households | 2010 |
| Padam Properties Ltd | Real estate | 2025 |
| Padua Communications Limited | Professional & scientific | 2010 |
| Pains Fireworks Limited | Arts & recreation | 1979 |
| Pains SFX Ltd | Arts & recreation | 2022 |
| Painted Warrior Ltd | Professional & scientific | 2021 |
| Panel Masters Limited | Other services | 2002 |
| Paragon Properties (Southern) Ltd | Construction | 2022 |
| Parc DEL Fryn 2 Management Company Limited | Households | 2024 |
| Park Gate Manor Management Company Limited | Households | 1987 |
| Parker Newman Decking Ltd | Wholesale & retail | 2019 |
| Parkfield Communications Limited | Professional & scientific | 2003 |
| Parsonage Enterprises Limited | Agriculture & fishing | 2015 |
| PATH2POTENTIAL Limited | Professional & scientific | 2025 |
| Paul Futcher Ltd | Wholesale & retail | 2016 |
| Pavilions 1 & 2 RTM Company Ltd | Administrative & support | 2021 |
| PD Developments (Hampshire) Ltd | Real estate | 2018 |
| PDQ Airspares Limited | Manufacturing | 1990 |