| LME Equine Therapeutic Centre CIC | Health & social care | 2023 |
| Location Solutions South West Limited | Information & communication | 2023 |
| Lodgeitech Ltd | Hospitality | 2025 |
| Longstone View Management Limited | Real estate | 2018 |
| Lottie-Loves Ltd | Wholesale & retail | 2010 |
| Louella Outdoor Living Limited | Manufacturing | 2024 |
| Lovegrove Construction Ltd | Construction | 2014 |
| Lowenna Fields (Falmouth) Management Company Limited | Households | 2016 |
| Lowenna House Management Company Limited | Households | 2017 |
| Lucie Rose Limited | Arts & recreation | 2019 |
| Lundy View Estates Limited | Energy | 2011 |
| Lundy View Properties Limited | Real estate | 2012 |
| LUX Kitchens & Bedrooms Ltd | Professional & scientific | 2023 |
| LUX Projects Ltd | Construction | 2023 |
| Luxulyan CLT Limited | Real estate | 2010 |
| Lysamber Residents Company Limited | Households | 2005 |
| M B Electrical (SW) Ltd | Construction | 2023 |
| M.A.H. Building Services Ltd | Construction | 2012 |
| M.S.Landway Ltd | Health & social care | 2020 |
| Madame Butterfly Limited | Other services | 2007 |
| Madhouse Splinter Ltd | Wholesale & retail | 2023 |
| Madonna Limited | Real estate | 2005 |
| Mahala Estates Limited | Construction | 2002 |
| Malcolm Barnecutt Bakery (Holdings) Limited | Manufacturing | 2012 |
| Malcolm Barnecutt Bakery (Properties) Limited | Manufacturing | 2013 |
| Malcolm Barnecutt Bakery Limited | Manufacturing | 2010 |
| Malpas House Residents Limited | Households | 2012 |
| Mandivein Limited | Administrative & support | 2013 |
| Marchwood Investments Limited | Financial services | 2006 |
| Mark Evans Property & Development Limited | Real estate | 2022 |
| Mark Pavitt Plumbing & Heating Limited | Construction | 2007 |
| Mark Trevethan Haulage Limited | Transport & logistics | 2007 |
| Market Place (ST Columb) Management Company Ltd | Real estate | 2016 |
| Marquand Agri Limited | Agriculture & fishing | 2022 |
| Marquees at Pencarrow LLP | | 2019 |
| Marsh Investments Limited | Construction | 1964 |
| Marshall Motors (SW) Limited | Wholesale & retail | 2013 |
| Martin Dairy Holdings Limited | Agriculture & fishing | 2022 |
| Martin Dairy Limited | Agriculture & fishing | 2010 |
| Marview Limited | Administrative & support | 2019 |
| Match Honey Ltd | Hospitality | 2018 |
| Mathy Ltd | Professional & scientific | 2021 |
| Mawgan Bay View Management Company Ltd | Households | 2019 |
| MC Property Upkeep Ltd | Administrative & support | 2025 |
| Mcilroy Builders Limited | Manufacturing | 2003 |
| Mcneela Investments Ltd | Administrative & support | 1993 |
| Measura Ltd | Construction | 2008 |
| Mechanical Auto Centre Ltd | Wholesale & retail | 2024 |
| Mendavision Services Limited | Construction | 2011 |
| Merchant Estate Control LLP | | 2006 |
| Merchant Tailor Ltd | Manufacturing | 2019 |
| Merrowgwidden Properties Limited | Hospitality | 2019 |
| Methodist Church Limited | Real estate | 2004 |
| MHE Holdings Limited | Real estate | 2019 |
| MID Cornwall 4 X 4 Parts & Accessories Ltd | Wholesale & retail | 2014 |
| MID Cornwall Brokers Ltd | Financial services | 2016 |
| Middle East Productions Ltd. | Information & communication | 2016 |
| Midnight Computing Limited | Information & communication | 1992 |
| Minchin & Grimshaw Ltd. | Professional & scientific | 2017 |
| MJH Carpentry & Construction Limited | Construction | 2019 |
| MJT Enterprises Limited | Arts & recreation | 1997 |
| MK Coffee & Nata Ltd | Hospitality | 2024 |
| MK Lounge Bar Limited | Hospitality | 2023 |
| Mmotive Ltd | Wholesale & retail | 2025 |
| Mobile Studio Tech & Repair Ltd | Wholesale & retail | 2025 |
| Mobility Centre Southwest Limited | Wholesale & retail | 2008 |
| Model Realm Limited | Wholesale & retail | 2013 |
| Mola's Child Ltd | Information & communication | 2025 |
| Monkeypig Productions Ltd | Arts & recreation | 2024 |
| MOO VET Consultancy Ltd | Professional & scientific | 2020 |
| Moor Accommodation Ltd | Real estate | 2018 |
| Moor Consulting Ltd | Professional & scientific | 2016 |
| Moore VEG Ltd | Agriculture & fishing | 2024 |
| Moorgoods Helicopters Limited | Transport & logistics | 1999 |
| Moorland Distillery Limited | Manufacturing | 2016 |
| Morrish Cleaning Limited | Administrative & support | 2021 |
| Morvargh Sailing Project CIC | Education | 2010 |
| Moss and Rowse Ltd | Real estate | 2022 |
| Mount Pleasant Holidays Limited | Hospitality | 2010 |
| MPS Property Group Ltd | Households | 2018 |
| Mulberry Rural Limited | Real estate | 2017 |
| Mustard Brands Limited | Wholesale & retail | 2020 |
| MW Highways Consulting Ltd | Professional & scientific | 2024 |
| My Advice IS Take Advice Limited | Extraterritorial | 2018 |
| My Home 4 Life Ltd | Real estate | 2008 |
| My Van MOT Ltd | Wholesale & retail | 2021 |
| N & a Jackson Limited | Professional & scientific | 2024 |
| N C Accounting Services Limited | Professional & scientific | 2016 |
| Nails of Dream Ltd | Other services | 2022 |
| Nankivell & Sons Limited | Agriculture & fishing | 2015 |
| Nathan Ball Music Limited | Information & communication | 2024 |
| NB Developments Ltd | Construction | 2025 |
| NB Saddlery Ltd | Manufacturing | 2017 |
| Nepa Hair and Beauty Ltd | Other services | 2026 |
| Neutron Fire Technologies Limited | Professional & scientific | 1999 |
| New Wave Group Ltd | Administrative & support | 2025 |
| Newton Lodge B&B Limited | Hospitality | 2017 |
| NF Transport Services Ltd | Transport & logistics | 2025 |
| Nicals Holding Company Limited | Real estate | 2018 |
| Nichola Jane Sinclair Ltd | Extraterritorial | 2024 |