| MD Automation Limited | Construction | 2003 |
| Mdmm Limited | Construction | 2007 |
| Meadow Cottages Management Company Limited | Households | 1988 |
| Meerose Property Limited | Households | 1978 |
| MEH Construction Management Ltd | Construction | 2009 |
| Mercury Transport Planning Ltd | Transport & logistics | 2025 |
| Merley House Holdings Limited | Hospitality | 2020 |
| Merley House Holiday Park Limited | Hospitality | 1966 |
| Merlin Fabrications Limited | Manufacturing | 1998 |
| Merriefield Limited | Professional & scientific | 2021 |
| Merriefield Propco Limited | Real estate | 2022 |
| Merriefield Properties Ltd | Real estate | 2026 |
| Metaskil Limited | Information & communication | 1986 |
| MFS Consultancy Limited | Professional & scientific | 2017 |
| MFS Sipp Property (UK) Limited | Real estate | 2026 |
| MG Composites Limited | Professional & scientific | 2006 |
| Michael Collins Electrical Ltd | Other services | 2018 |
| Microaces Limited | Manufacturing | 2011 |
| Midnight Circus Branded Ltd | Information & communication | 2019 |
| Midnight Circus Films Ltd | Information & communication | 2014 |
| Miles & SON Limited | Real estate | 2013 |
| Minnell Motors Limited | Administrative & support | 2002 |
| Minster Chefs Limited | Other services | 2011 |
| Misan Assistance Limited | Professional & scientific | 2002 |
| MJC Ceilings and Walls Limited | Construction | 2023 |
| MK3DESIGNS (Dorset) Ltd | Construction | 2018 |
| MMH Investments Limited | Real estate | 2025 |
| Money Marvel Limited | Financial services | 2006 |
| Moneyback Mortgages Limited | Administrative & support | 2017 |
| Mother Land Supplies Ltd | Manufacturing | 2024 |
| Motivated Performance Limited | Extraterritorial | 2018 |
| Movement AV Limited | Wholesale & retail | 2013 |
| MPH Renewables Ltd | Wholesale & retail | 2023 |
| MPS Building Property Group Ltd | Real estate | 2026 |
| MV Talent Solutions Ltd | Administrative & support | 2023 |
| N&C Holdings Ltd | Professional & scientific | 2015 |
| NAM HAI Limited | Other services | 2023 |
| Narieda Ltd | Professional & scientific | 2024 |
| Nataya Home Care Ltd | Health & social care | 2026 |
| New Driver Schools of Motoring (Registry and Administration) Limited | Education | 1988 |
| Newfield Partners Limited | Health & social care | 2025 |
| Newton Magnus Ltd | Professional & scientific | 2002 |
| Next to Sea Design Ltd | Manufacturing | 2025 |
| Nico Sports Limited | Arts & recreation | 2006 |
| NJS Construction Limited | Construction | 2019 |
| NM Optical Limited | Health & social care | 2005 |
| Nostalgia Emporium Ltd | Wholesale & retail | 2022 |
| Nwtgr Limited | Arts & recreation | 2022 |
| O-Group Security Ltd | Administrative & support | 2026 |
| Okapi Legal Recruitment Ltd | Administrative & support | 2021 |
| Olibee Sports Ltd | Arts & recreation | 2022 |
| Online SAX Academy Ltd | Education | 2023 |
| Opal I Solutions Ltd | Professional & scientific | 2014 |
| Orange Property Solutions Ltd | Administrative & support | 2024 |
| Orchard Blue Limited | Financial services | 1995 |
| Orion View Ltd | Real estate | 2025 |
| P.L. Matthews Plumbing & Heating Limited | Construction | 1998 |
| Paddington Productions Ltd | Information & communication | 2018 |
| Palace Digital Marketing Limited | Professional & scientific | 2021 |
| Paladium Holdings Ltd | Financial services | 2019 |
| Panta-Rei Psychology at Work Ltd | Health & social care | 2016 |
| Parkstone Car Care Ltd | Wholesale & retail | 2003 |
| Parnell Electrical Ltd | Wholesale & retail | 2026 |
| Parr House (1987) Management Company Limited | Households | 1988 |
| Pascall & Associates Ltd | Financial services | 2016 |
| Pathway Mortgages Ltd | Financial services | 2026 |
| Paul Benham Limited | Professional & scientific | 2015 |
| Paul Newton Consultants Limited | Public administration | 2014 |
| Paula LEE Ltd | Other services | 2014 |
| Payne & Cherrett Builders Ltd | Construction | 2021 |
| Pazi Fitness Coaching Ltd | Arts & recreation | 2021 |
| PB Property Renovations Limited | Construction | 2015 |
| Pearl Plastering Ltd | Construction | 2023 |
| Peeku & Gogi Ltd | Wholesale & retail | 2021 |
| Penny Films Ltd | Arts & recreation | 2022 |
| Pereira Holdings Ltd | Financial services | 2020 |
| Pereira Ltd | Real estate | 2025 |
| Peter Ostling Motor Service Specialist Limited | Wholesale & retail | 2011 |
| Phil Dove Transport Ltd | Transport & logistics | 2024 |
| Phvr Engineering Limited | Administrative & support | 1999 |
| Pinnacle Marine Ltd | Manufacturing | 2023 |
| Pioneer Helicopters Ltd | Transport & logistics | 2022 |
| Pipcom Limited | Manufacturing | 1985 |
| Pjsb Ventures Ltd | Financial services | 2024 |
| Plantable Store Ltd | Manufacturing | 2022 |
| Pmet Ltd. | Professional & scientific | 2016 |
| Pomeroy Ltd | Information & communication | 2010 |
| Poole Harbour Residential and Commercial Ltd | Real estate | 2023 |
| Poole Harbour Taxis Limited | Transport & logistics | 2008 |
| Poole North PCN Limited | Health & social care | 2024 |
| Poole Orthodontics Ltd | Health & social care | 2019 |
| Poole Quay Fish Bar Ltd | Hospitality | 2015 |
| Poole Software Limited | Information & communication | 2017 |
| Poole Views Ltd | Real estate | 2023 |
| Poppies Catering Ltd | Hospitality | 2025 |
| Portus Developments Ltd | Construction | 2024 |
| Portus Homes Ltd | Construction | 2010 |
| Ppcs Pest Control Ltd | Administrative & support | 2021 |
| Pravinia Ltd | Real estate | 2025 |
| Premier Saffron Ltd | Wholesale & retail | 2014 |