| Marine Discovery Penzance Ltd | Professional & scientific | 2026 |
| Marion Russell Consultancy Ltd | Professional & scientific | 2021 |
| Marisco Fish Limited | Wholesale & retail | 2007 |
| Mark Roderick Building Services Ltd | Construction | 2016 |
| Market House Penzance C.I.C. | Administrative & support | 2023 |
| Market Place Penzance C.I.C. | Real estate | 2026 |
| Martins’ Marquees Ltd | Construction | 2026 |
| Marymidd Solutions Limited | Professional & scientific | 2019 |
| Mason Kelly Limited | Real estate | 2015 |
| Matthew Harvey Rentals Limited | Real estate | 2020 |
| Matthews Developments Limited | Construction | 2020 |
| Matthews Orthopaedic Surgical Services Limited | Health & social care | 2015 |
| Maxum Homes Ltd | Construction | 2006 |
| Mayon Farm Management Limited | Households | 1997 |
| Mbvc Trustees Ltd | Professional & scientific | 2025 |
| MBX Medical Ltd | Health & social care | 2023 |
| Mcatee Property Group Limited | Households | 2023 |
| Mcfadden Estates Ltd | Construction | 2017 |
| MCJ Carpentry Ltd | Construction | 2023 |
| Mckinnon-Jardine Leisure Limited | Hospitality | 2015 |
| Meadows Kitchens Ltd | Manufacturing | 2017 |
| Meaningful Coaching Limited | Professional & scientific | 2024 |
| Meaningful Money Limited | Education | 2011 |
| Medical Consultancy Services UK Limited | Professional & scientific | 2021 |
| Mercer Tax and Management Limited | Professional & scientific | 1994 |
| Mercman Parts Ltd | Wholesale & retail | 2019 |
| Meridian Bluestar Limited | Real estate | 2025 |
| Mester MOR Limited | Hospitality | 2023 |
| MGC Surgical Services Limited | Health & social care | 2017 |
| Michael Hagan Ltd | Professional & scientific | 2019 |
| Michael Praed Limited | Arts & recreation | 2014 |
| Millhouse Carpets Limited | Wholesale & retail | 2014 |
| Millpool (Mousehole) Management Company Limited | Households | 1997 |
| Millpool Property Ltd | Construction | 2017 |
| Minack Productions Limited | Arts & recreation | 2021 |
| Miner Property Lets Ltd | Real estate | 2026 |
| Minerva RA Ltd | Professional & scientific | 2025 |
| Mirva Gallery Collective CIC | Wholesale & retail | 2018 |
| Misosmart Limited | Information & communication | 2020 |
| MJ Coach Ltd | Other services | 2024 |
| MJ Orthopaedics Limited | Health & social care | 2013 |
| MJS Second Hand Furniture Limited | Wholesale & retail | 2002 |
| Mkei Limited | Financial services | 2026 |
| Mojo MAC Limited | Other services | 1996 |
| Montol Festival CIC | Arts & recreation | 2023 |
| Moonlight Editions Ltd | Wholesale & retail | 2022 |
| MOR Holan Sauna & Wild Spa Ltd | Other services | 2023 |
| Morgan Webber Limited | Professional & scientific | 2013 |
| Morrab Pharma Ltd | Wholesale & retail | 2023 |
| Morrab Pharmacy Limited | Wholesale & retail | 2016 |
| Mount Lidden Limited | Transport & logistics | 2005 |
| Mount Street Chapel Limited | Households | 2000 |
| Mount View Developments Ltd | Construction | 2023 |
| Mount's Bay Trading Ltd | Construction | 2011 |
| Mounts Bay Accountants Ltd | Professional & scientific | 2021 |
| Mounts Bay Coaches Limited | Transport & logistics | 1998 |
| Mounts Bay Construction Ltd | Construction | 2025 |
| Mounts Bay Dairy Limited | Wholesale & retail | 2012 |
| Mounts Bay Distillery Limited | Manufacturing | 2020 |
| Mounts Bay Holdings Limited | Real estate | 2025 |
| Mounts Bay Linen Hire Ltd | Other services | 2014 |
| Mounts Bay Living Holding Limited | Financial services | 2017 |
| Mounts Bay Microcement Limited | Construction | 2021 |
| Mounts Bay Veterinary Centre Limited | Professional & scientific | 2009 |
| Mousehole AFC Football and Social Club Limited | Arts & recreation | 2016 |
| Mousehole Camping Limited | Hospitality | 2026 |
| Mousehole Harbour Lights CIC | Professional & scientific | 2025 |
| Mousehole Wild Bird Hospital and Sanctuary Association Limited | Professional & scientific | 1976 |
| MPL Groundwork & Building Limited | Construction | 2020 |
| MR B'S Natural Skincare Ltd | Manufacturing | 2025 |
| MR Bassett's Ltd | Manufacturing | 2022 |
| MR Magoo Ltd | Administrative & support | 2019 |
| Multesign Systems (UK) Limited | Administrative & support | 2005 |
| Musicability Community Interest Company | Education | 2017 |
| Mustard FX Limited | Manufacturing | 2024 |
| Musura Ltd | Professional & scientific | 2026 |
| MW Renovations Limited | Construction | 2021 |
| My Ielts World Ltd | Education | 2018 |
| My Management & Maintenance Ltd | Real estate | 2003 |
| N a Pinkett Ltd | Education | 2002 |
| N H Semmens & SON Limited | Agriculture & fishing | 2003 |
| NA4C Limited | Health & social care | 2022 |
| Nance Provisions CIC | Education | 2025 |
| Nanceddan Limited | Real estate | 2007 |
| Nancherrow Developments Limited | Construction | 2003 |
| Nanpean Barn Management Company Limited | Households | 2006 |
| Napoli Bar PZ Limited | Hospitality | 2026 |
| Natashas Songs Ltd | Information & communication | 2002 |
| Natoso Limited | Administrative & support | 2009 |
| Nature's Plate Limited | Hospitality | 2015 |
| Naut Limited | Hospitality | 2021 |
| Neilsonco Limited | Hospitality | 2021 |
| Nells Housekeeping Limited | Administrative & support | 2021 |
| Nells Laundry Services Ltd | Other services | 2023 |
| Neonica Ltd | Professional & scientific | 2002 |
| NET Zero Cornwall Ltd | Professional & scientific | 2022 |
| Neuro-Inclusive Learning Umbrella CIC | Education | 2025 |
| New Mill Properties Limited | Extraterritorial | 1962 |
| Newball Limited | Hospitality | 2012 |
| Newline Chandlery Limited | Wholesale & retail | 2002 |