| LJ O'Brien Ltd | Professional & scientific | 2012 |
| LMR Group Limited | Professional & scientific | 2024 |
| Lock Interior Contractors Limited | Construction | 2002 |
| Loggershop Limited | Manufacturing | 2012 |
| Loose Reins Glamping Ltd | Hospitality | 2026 |
| LOW Energy Designs Ltd | Manufacturing | 2007 |
| LSJ Services Dorset Ltd | Wholesale & retail | 2025 |
| LSP Advisory UK Ltd | Information & communication | 2018 |
| Luccombe EAQ Ltd | Education | 2019 |
| Lucian Entertainment Limited | Information & communication | 2026 |
| Lucidnations Ltd | Information & communication | 2023 |
| Luxury Nails Blandford Limited | Other services | 2024 |
| Lvbf Ltd | Hospitality | 2025 |
| LX Exhibition & Event Services Limited | Energy | 2009 |
| M & D Consultants Limited | Information & communication | 2004 |
| M & L Builders (Dorset) Ltd | Construction | 2019 |
| M C Bistro Limited | Hospitality | 2023 |
| M L Best Limited | Construction | 2004 |
| M Squared Ventures Limited | Wholesale & retail | 2022 |
| M T Box & Company Limited | Transport & logistics | 2013 |
| M.A.J. Domestic & Commercial Cleaning Services Limited | Other services | 2020 |
| M.C. Simpson (PAS) Limited | Agriculture & fishing | 2005 |
| M.G. Trevett Limited | Manufacturing | 1978 |
| M33YER Ltd | Professional & scientific | 2025 |
| MAC Transport (UK) Limited | Wholesale & retail | 2002 |
| Madden Motors Limited | Wholesale & retail | 2023 |
| Mahi Marine Limited | Professional & scientific | 2021 |
| Mainestate Limited | Information & communication | 1998 |
| Maintain Property South Ltd | Construction | 2026 |
| Makkow UK Ltd | Wholesale & retail | 2020 |
| Management Education & Development Ltd | Administrative & support | 2015 |
| Manic Monster Warehouse Limited | Arts & recreation | 2009 |
| Manor Equestrian Livery Limited | Agriculture & fishing | 2026 |
| Marcus Consulting Ltd | Professional & scientific | 2022 |
| Marlborough House (Maidenhead) Management Company Limited | Real estate | 1986 |
| Martins Deverel Limited | Real estate | 2007 |
| Matrix Partnership Limited | Professional & scientific | 2000 |
| Matt Tiling Limited | Construction | 2022 |
| Maude & FOX Ltd | Manufacturing | 2011 |
| MAW Hydrographic Ltd | Professional & scientific | 2026 |
| Maxfield & Dyer Mixology Ltd | Hospitality | 2024 |
| MBT House Renovation Limited | Construction | 2024 |
| Mcadam Specialist Polishing Ltd | Manufacturing | 2018 |
| Mcmanus IT Consultants Ltd | Information & communication | 2023 |
| Meade & SON Property Ltd | Real estate | 2025 |
| Meadow Property Management Limited | Real estate | 2003 |
| Medium Rare Music Ltd | Information & communication | 2014 |
| Meeting Norm Limited | Hospitality | 2025 |
| Meggy Moo's Limited | Hospitality | 2015 |
| Memco Trading Limited | Real estate | 2020 |
| Mercator Global Enterprises Ltd | Professional & scientific | 2013 |
| Meyts Structural Consulting Limited | Professional & scientific | 2010 |
| Michael James Financial Planning Limited | Financial services | 2012 |
| Mick Berry Plumbing & Heating Services Ltd | Construction | 2016 |
| Mick MAC Tyres & Transport Services Ltd | Extraterritorial | 2014 |
| Milborne Deverel Limited | Hospitality | 2011 |
| Million Pound Pineapple Ltd | Wholesale & retail | 2023 |
| Milton Projects (Dorset) Ltd | Construction | 2023 |
| Mimesis Studios Ltd | Information & communication | 2020 |
| Mj&B PVT Ltd | Hospitality | 2020 |
| MJT NET Ltd | Information & communication | 1997 |
| MK Engineering Blandford Ltd | Professional & scientific | 2024 |
| Mobile Auto Electricians Limited | Wholesale & retail | 2025 |
| Modular Exhibition Stands Limited | Other services | 2018 |
| Modus Systems Group Ltd | Information & communication | 2026 |
| Moglia Consultancy Limited | Professional & scientific | 2018 |
| Monica Tory Ltd | Agriculture & fishing | 2022 |
| Morgan Companies Limited | Real estate | 2018 |
| Morgan Singleton Ltd | Real estate | 2020 |
| MRA Geotechnics Limited | Professional & scientific | 2007 |
| MS Books Ltd | Professional & scientific | 2018 |
| MS Hunston Group Ltd | Arts & recreation | 2026 |
| MTS Petra Limited | Wholesale & retail | 2025 |
| Muddy Monkies Limited | Health & social care | 2018 |
| Murrill Construction Limited | Construction | 1985 |
| Murrill Holdings Limited | Financial services | 2015 |
| Murrill Signs Limited | Manufacturing | 2015 |
| MVS Blandford Limited | Wholesale & retail | 2012 |
| My Own Tutor Limited | Education | 2016 |
| N D Motors Servicing and Repairs Limited | Wholesale & retail | 2015 |
| N D Young Transport Limited | Transport & logistics | 2002 |
| N.Ellis Building and Groundworks Ltd | Construction | 2021 |
| N1BNR Ltd | Wholesale & retail | 2020 |
| NAB PUB Ltd | Extraterritorial | 2013 |
| Narla BIO Ltd | Professional & scientific | 2023 |
| Natalie's DEN Limited | Health & social care | 2025 |
| Natasha Solomons Ltd | Information & communication | 2024 |
| Naturiol Ltd. | Manufacturing | 2020 |
| Needham Tree Specialists Ltd | Administrative & support | 2025 |
| NET X Solutions Limited | Information & communication | 2001 |
| Netview Software Systems Ltd | Information & communication | 2021 |
| Newbi Ltd | Professional & scientific | 2020 |
| Newport Management Limited | Professional & scientific | 2015 |
| Newstart Health Ltd | Health & social care | 2016 |
| Newton Haygarth Ventures Ltd | Financial services | 2018 |
| Nexis Lighting Ltd | Wholesale & retail | 2024 |
| Nexus Recruitment Group Limited | Administrative & support | 2024 |
| Nguni Hospitality Ltd | Hospitality | 2025 |
| Nicholas Walton Limited | Manufacturing | 2025 |
| Nicholas Weeks Limited | Construction | 2001 |