| Killiers Court Management Limited | Households | 1991 |
| Kimberley Estates Limited | Professional & scientific | 1997 |
| King Harry Coaches Limited | Transport & logistics | 2002 |
| KML Financial Services Limited | Financial services | 2003 |
| Korner Kabin Limited | Wholesale & retail | 2003 |
| L.Best & Son,Limited | Real estate | 1952 |
| L.J.Tregunna(Builders)Limited | Construction | 1961 |
| Lamorna Express Limited | Transport & logistics | 2003 |
| Land's END Airport Limited | Transport & logistics | 1970 |
| Land's END Hotel Limited | Wholesale & retail | 1993 |
| Lands END John O'Groats Association Limited | Other services | 2002 |
| Lanes of Cornwall Limited | Extraterritorial | 2006 |
| Lanes of Devon Ltd | Extraterritorial | 2006 |
| Langley Marsh Limited | Financial services | 2007 |
| Lanhydrock Accountancy Practice Limited | Professional & scientific | 2007 |
| Lansdown Dairy Limited | Extraterritorial | 2006 |
| Lappa Valley Railway Company Limited | Arts & recreation | 1973 |
| LBL Business Accounting Ltd | Professional & scientific | 2007 |
| LEE Henderson Ltd | Professional & scientific | 2018 |
| Lerryn River Drinks Company Limited | Manufacturing | 2024 |
| Libra SW Ltd | Real estate | 2023 |
| Lighthouse Developments (SW) Limited | Extraterritorial | 2006 |
| Lilley Fitter's Cornish Pasties Limited | Construction | 1998 |
| Lillie Brothers Limited | Manufacturing | 2007 |
| Lilly Lewarne Practice Limited | Professional & scientific | 2006 |
| Limitrand Limited | Households | 1977 |
| Lindsay Ellacott UK Ltd. | Wholesale & retail | 1997 |
| Linea Studio Limited | Professional & scientific | 2004 |
| Liskeard Classic Cars Limited | Extraterritorial | 2007 |
| Liskerrett Community Centre | Administrative & support | 1999 |
| Little Trewinnick Farm Limited | Professional & scientific | 2002 |
| Livingston's Jewellers Limited | Wholesale & retail | 2003 |
| Looe Valley Vineyard Limited | Agriculture & fishing | 2006 |
| Lovetts of Newlyn Ltd | Hospitality | 2021 |
| M & M Plastic Industries Limited | Manufacturing | 1970 |
| M & M Scaffolding (Cornwall) Ltd | Construction | 2006 |
| M F Rowlands Limited | Construction | 2006 |
| M J Jarvis Limited | Construction | 2005 |
| M.P.B. Engineering (Falmouth) Limited | Manufacturing | 1999 |
| Mably Farms Limited | Agriculture & fishing | 1961 |
| Macmillans (Wadebridge) Limited | Real estate | 1989 |
| Make IT Rame Ltd | Construction | 2025 |
| Malcolm Heard & Associates Limited | Professional & scientific | 2002 |
| Marazion Holdings Limited | Professional & scientific | 1996 |
| Marconi Builders and Developers Limited | Construction | 2000 |
| Marine Resource Management Limited | Professional & scientific | 2007 |
| Market Street Clinic Ltd | Health & social care | 2002 |
| Market Street Properties (South West) Limited | Administrative & support | 2000 |
| Martin Body Limited | Agriculture & fishing | 1938 |
| Mass.Cad Limited | Professional & scientific | 1990 |
| MB Consultancy Limited | Other services | 2004 |
| Mbtp Ltd | Arts & recreation | 2021 |
| Medimax Limited | Health & social care | 1999 |
| Melrose Court (Newquay) Limited | Households | 2003 |
| Mercator Schools Limited | Education | 1987 |
| Metropolis Media (Investments) Limited | Extraterritorial | 1998 |
| Mevagissey Garages Limited | Wholesale & retail | 1954 |
| Michael Beardsall Associates Limited | Professional & scientific | 2003 |
| Milestone Engineering Design Limited | Administrative & support | 2003 |
| Miller Commercial Valuers Limited | Real estate | 1998 |
| Miraid Construction Limited | Construction | 1999 |
| Mission Code Southwest Ltd | Professional & scientific | 2022 |
| Mission Construction Solutions Ltd | Construction | 2021 |
| Morcom Construction Limited | Construction | 2002 |
| Morrab Road Management Company Limited | Households | 2004 |
| Morvah Action for the Community and Arts Limited | Arts & recreation | 1998 |
| Motor Sport Solutions Limited | Transport & logistics | 2000 |
| Mounts Bay Living Limited | Construction | 2000 |
| Movevirgo Limited | Manufacturing | 1982 |
| Mundic Nation Limited | Information & communication | 2002 |
| My Continuum Financial Nominee Limited | Professional & scientific | 2021 |
| Mylor Chandlery Ltd | Wholesale & retail | 2002 |
| Mylor Yacht Harbour (Holding Company) Limited | Professional & scientific | 1998 |
| Mylor Yacht Harbour Limited | Transport & logistics | 1961 |
| N P Construction Limited | Construction | 2005 |
| N.R.E.A. Limited | Information & communication | 1980 |
| National Maritime Museum Cornwall Trust | Arts & recreation | 1997 |
| Nelson Stokes Group Limited | Manufacturing | 1990 |
| New Dawn Traders Ltd | Wholesale & retail | 2013 |
| Newhouse Mill Limited | Agriculture & fishing | 2005 |
| Newquay Boardriders Limited | Wholesale & retail | 2007 |
| Newquay Creameries Limited | | 1966 |
| Newquay Refrigeration & Airconditioning Limited | Manufacturing | 2003 |
| Nicholls Plant Hire Limited | Other services | 2017 |
| Noodleman Moon Ltd | Financial services | 2021 |
| Noushka Design Ltd | Professional & scientific | 2012 |
| Oasis BLU Limited | Real estate | 2006 |
| Objectiveitservices.Com Ltd | Information & communication | 2000 |
| ON the Rocks Bar Newquay Limited | Hospitality | 2004 |
| Onamass Television Limited | | 1977 |
| Openconcept Residents Management Limited | Households | 1987 |
| Optical Service (UK) Limited | Wholesale & retail | 1993 |
| Orchid Trading Limited | | 2004 |
| Orion Projects Limited | Manufacturing | 1987 |
| Overland Limited | Other services | 1994 |
| P & C Giles Ltd | Wholesale & retail | 2005 |
| P C Tonkin & SON Limited | Wholesale & retail | 2007 |
| P W Marshall Ltd | Wholesale & retail | 2005 |
| P&R Mast Ltd | Professional & scientific | 2021 |
| P.R Developments (South West) Limited | Construction | 2007 |