| Lozmark Properties Ltd | Real estate | 2016 |
| LRM Resources Ltd | Construction | 2025 |
| LSM Engineering Ltd | Professional & scientific | 2023 |
| Luke Allum Funeral Directors Limited | Other services | 2017 |
| Luxe Loot Ltd | Wholesale & retail | 2025 |
| Lvaidas Logistics Ltd | Transport & logistics | 2022 |
| Lynne Collins Property Ltd | Real estate | 2023 |
| M Lunan Plastering Limited | Construction | 2008 |
| M&U Beauty Ltd | Wholesale & retail | 2021 |
| M.Jordan Services Ltd | Construction | 2020 |
| M91 Civils Ltd | Construction | 2023 |
| MAD About People Limited | Administrative & support | 2011 |
| MAG Transport Ltd | Transport & logistics | 2019 |
| Maidenhead Hand Car Wash Ltd | Wholesale & retail | 2025 |
| Mak&Kam Ltd | Transport & logistics | 2025 |
| Make IT Account Limited | Professional & scientific | 2025 |
| Makee Design Limited | Information & communication | 2016 |
| Malro Homes Limited | Real estate | 1992 |
| Malro Investments Limited | Real estate | 1976 |
| MAN UP Ltd | Manufacturing | 2011 |
| Mango VFX Limited | Information & communication | 2017 |
| Mannering Entertainment Limited | Information & communication | 2014 |
| Mannys Sauces Limited | Manufacturing | 2013 |
| Manny’S UK Services Limited | Wholesale & retail | 2022 |
| Mansfield Drive Management Limited | Households | 2002 |
| Marine Gears UK Ltd | Manufacturing | 2017 |
| Marinus Ltd | Wholesale & retail | 2010 |
| Maryamfrank Enterprises Ltd | Professional & scientific | 2016 |
| MAS European Logistics Limited | Transport & logistics | 2024 |
| Masterbuild Plastics Limited | Construction | 1988 |
| Mastercuts (Sheppey) Limited | Other services | 2005 |
| Matjeffery.Com Ltd | Other services | 2014 |
| Maywood Holdings Ltd | Financial services | 2024 |
| Maze Security Limited | Construction | 2009 |
| Mcg-Hv Limited | Professional & scientific | 2019 |
| MDN Data Comm Cabling Limited | Information & communication | 2008 |
| Meadow View Eastchurch Management Company Ltd | Households | 2025 |
| Medilax Limited | Administrative & support | 2015 |
| Medipharm Trading Limited | Financial services | 2022 |
| Megadale Limited | Real estate | 1979 |
| Melissa Ansah Ltd | Professional & scientific | 2023 |
| Melville Heating Limited | Construction | 2012 |
| Men-Talk.Uk Community Interest Company | Health & social care | 2023 |
| Merero Engineering Ltd | Professional & scientific | 2023 |
| Merriott Art and Technical Limited | Professional & scientific | 2004 |
| Messy Pups Limited | Hospitality | 2026 |
| MG Control Solutions Limited | Information & communication | 2012 |
| MHD Rochester Trading Ltd | Real estate | 2024 |
| Michad Properties Limited | Real estate | 2018 |
| Michael Corps Limited | Administrative & support | 2020 |
| Michal Perlowski Ltd | Transport & logistics | 2014 |
| MIG Transport Services Ltd | Transport & logistics | 2021 |
| Milestone Agencies Limited | Wholesale & retail | 2010 |
| Mills Navigation Ltd. | Manufacturing | 2017 |
| Millwall Mechanical Limited | Manufacturing | 2014 |
| Ministry of Spice Ltd | Education | 2019 |
| Minster Beach Management Company Ltd | Households | 2022 |
| Minster Cafe Limited | Hospitality | 2025 |
| Minster Haulage & Road Sweepers Ltd | Transport & logistics | 2025 |
| Minster Powerwashing Ltd | Administrative & support | 2026 |
| Mission Bay Smiles Ltd | Health & social care | 2025 |
| Misstig Limited | Hospitality | 2023 |
| Mister Gooo Limited | Transport & logistics | 2016 |
| MJ Roofing & Landscaping Ltd | Construction | 2025 |
| ML Creative Developments Ltd | Real estate | 2013 |
| MLE Shopping Limited | Extraterritorial | 2019 |
| Mmpc Limited | Construction | 2017 |
| Mobituk Ltd. | Wholesale & retail | 2014 |
| Momentum Plant Ltd | Administrative & support | 2024 |
| Mondo Dent Ltd | Wholesale & retail | 2025 |
| Moritz Ltd | Professional & scientific | 2013 |
| Mortgage Superheroes Limited | Financial services | 2015 |
| Mortimer Holdings Management Limited | Administrative & support | 2024 |
| Mortimer House Management Limited | Administrative & support | 2024 |
| Moss Electrical Kent Ltd | Construction | 2023 |
| Moss Properties Kent Limited | Real estate | 2024 |
| Moss Property Services Kent Limited | Construction | 2024 |
| Mpdw Training Services Ltd | Education | 2021 |
| MPG Electrical Contractor Limited | Construction | 2025 |
| MR. Woofward & Co. Ltd | Agriculture & fishing | 2021 |
| MS Design Studio Ltd | Professional & scientific | 2025 |
| Msi-Serv Limited | Transport & logistics | 2018 |
| MTA Creations Ltd | Wholesale & retail | 2023 |
| MTG GAS Services Ltd | Construction | 2025 |
| Mullawave Ltd | Manufacturing | 2025 |
| Munday Power Group Ltd | Construction | 2026 |
| Munns Construction Ltd | Construction | 2018 |
| Murdoch UK Limited | Wholesale & retail | 2006 |
| Mwjcontracting Ltd | Professional & scientific | 2025 |
| My Urban Pet Ltd | Wholesale & retail | 2025 |
| Mykliner Ltd | Information & communication | 2025 |
| N D Tasker Ltd | Construction | 2023 |
| N H Developments (Kent) Limited | Construction | 2006 |
| N.O.C-Eli-Shay Limited | Construction | 2020 |
| Nagata & Matthews Ltd | Health & social care | 2021 |
| Narrow Gauge Railway Society | Other services | 2015 |
| NAT Runs Ltd | Professional & scientific | 2024 |
| National Fire & Security Contractors Limited | Administrative & support | 2023 |
| National Night Safety Partnership Ltd | Administrative & support | 2025 |
| Natural Equilibrium CIC | Professional & scientific | 2026 |