| KIT Johns Art Limited | Arts & recreation | 2022 |
| Kitchen and Brown Accountants Ltd | Professional & scientific | 2022 |
| Kitely Homes Ltd | Real estate | 2022 |
| KJB Coffee Co. Limited | Hospitality | 2024 |
| Kjcj Limited | Real estate | 2001 |
| Kobe Media Limited | Professional & scientific | 2024 |
| Kona (Falmouth) Ltd | Hospitality | 2024 |
| Kosel Ltd | Hospitality | 2021 |
| KSS Contracts Ltd | Construction | 2026 |
| KSS SW Ltd | Construction | 2019 |
| KWK Pro CIC | Information & communication | 2025 |
| Kyfy Limited | Professional & scientific | 2023 |
| Kynance Cafe Limited | Wholesale & retail | 2010 |
| Lady Hamilton Helford Ltd | Agriculture & fishing | 2021 |
| Landberry Engineers Ltd | Administrative & support | 2010 |
| Landstone Construction Limited | Construction | 2012 |
| Lanyon Holiday Park Limited | Hospitality | 2020 |
| Laurels Holiday Park Ltd | Hospitality | 2022 |
| Law Construction Cornwall Ltd | Construction | 2011 |
| Lawson Electrical Contractors Limited | Construction | 2022 |
| LB Commercial Cleaning Ltd | Administrative & support | 2025 |
| Lemon Bell Limited | Hospitality | 2022 |
| Lemon Inc. Limited | Hospitality | 2025 |
| Let’S Cuddle UP Ltd | Manufacturing | 2025 |
| Lewis Projects Ltd | Information & communication | 2017 |
| Leyland Brothers Limited | Real estate | 2014 |
| LIG Consulting Limited | Professional & scientific | 2011 |
| LIG Events Limited | Professional & scientific | 2018 |
| Lindford House Holiday Cottages Limited | Administrative & support | 2002 |
| Link Business Finance Limited | Financial services | 2006 |
| Lion and Lamb Helston Limited | Hospitality | 2024 |
| Little Legs Lamb Ltd | Agriculture & fishing | 2024 |
| Little Miss Orchard Ltd | Administrative & support | 2023 |
| Little Nuggets Property Ltd | Real estate | 2025 |
| Little Trevothan Limited | Hospitality | 2016 |
| Little Wilderness Ltd | Agriculture & fishing | 2020 |
| Liveable Years Ltd | Wholesale & retail | 2022 |
| Living Sea Therapy Limited | Real estate | 2019 |
| Lizard Airsoft Supplies Ltd | Wholesale & retail | 2018 |
| Lizard Cleaning & Maintenance Ltd | Administrative & support | 2021 |
| Lizard Concepts Limited | Hospitality | 2015 |
| Lizard Marine Services Ltd | Professional & scientific | 2007 |
| Lizard Yacht Services Ltd | Manufacturing | 2021 |
| LJ Benfield Developments Ltd | Real estate | 2025 |
| Lloyd Turner Limited | Construction | 1999 |
| LOE Bar Apartments Management Company Limited | Real estate | 2009 |
| Longstone Farm Services Ltd | Construction | 2024 |
| Losowen Limited | Hospitality | 2013 |
| Lost Token Ltd | Information & communication | 2020 |
| Lovebite Creative Productions LLP | | 2024 |
| Lowarn Developments Ltd | Construction | 2025 |
| Lowarn HR Ltd | Administrative & support | 2025 |
| Lowdon Design Limited | Professional & scientific | 2022 |
| Lower Polladras Holiday Park Ltd | Hospitality | 2020 |
| Lower Trewennack Farm Management Company Limited | Real estate | 2003 |
| LP Digital Ltd | Information & communication | 2020 |
| Lttrbx Limited | Wholesale & retail | 2019 |
| Luggage Transfers Ltd | Transport & logistics | 2009 |
| Luke Bellamy Fabrications Ltd | Manufacturing | 2014 |
| LZ Beijing Cuisine Limited | Hospitality | 2018 |
| M & N Construction Helston Ltd | Construction | 2021 |
| M & W Property Developments Ltd | Construction | 2018 |
| M.P.B. Marine Services Limited | Mining & quarrying | 2011 |
| M.R. Evans and Sons (Builders) Limited | Construction | 2011 |
| M365 Consulting Ltd | Extraterritorial | 2021 |
| MA Dearden Limited | Manufacturing | 2018 |
| Mabel's Daughter Ltd | Manufacturing | 2023 |
| Machinable Ltd | Professional & scientific | 2023 |
| Mackeng Ltd | Professional & scientific | 2018 |
| Maev Enterprise Ltd | Other services | 2017 |
| Magic Dolphin Ltd | Mining & quarrying | 2023 |
| Mainsail Property Investment Limited | Real estate | 2018 |
| Make IT Future Limited | Information & communication | 2025 |
| Mamm + Myrgh Goldsmiths Limited | Manufacturing | 2016 |
| Mandala World Travel Ltd | Administrative & support | 2022 |
| Manuel Cornwall Ltd | Health & social care | 2018 |
| Marine OPS Ltd | Information & communication | 2026 |
| Marine Protective Films Ltd | Manufacturing | 2021 |
| Maritime Defence Consultancy Limited | Professional & scientific | 2021 |
| Market House Abingdon Limited | Households | 2026 |
| Married in Cornwall Limited | Administrative & support | 2018 |
| Martin Support Services Ltd | Health & social care | 2010 |
| Mash Construction Ltd | Construction | 2024 |
| Mash Group Inc Ltd | Real estate | 2025 |
| Mastars Industries (Europe) Ltd | Professional & scientific | 2012 |
| Masuko Limited | Hospitality | 2024 |
| Matt Fynes Environmental Ltd | Professional & scientific | 2017 |
| Mccarron Coaching Limited | Health & social care | 2026 |
| Meadowsweet Horticulture CIC | Agriculture & fishing | 2025 |
| Medical & General Insurance Solutions Ltd | Financial services | 2020 |
| Medlyns Court Management Company Limited | Hospitality | 1988 |
| Meneage Dental Care Limited | Health & social care | 2011 |
| Meneage EOT Ltd | Professional & scientific | 2022 |
| Meticulous Maids Ltd | Administrative & support | 2021 |
| METRE2 LLP | | 2011 |
| MFE Services Limited | Administrative & support | 2026 |
| MG Music Limited | Arts & recreation | 2002 |
| MGS Maintenance Cornwall Ltd | Manufacturing | 2019 |
| Middlewick Surveyors Ltd | Professional & scientific | 2022 |
| Mike Bury Plumbing Ltd | Construction | 2018 |