| Mackinac Ltd | Professional & scientific | 2012 |
| Made in the Dales Limited | Arts & recreation | 2013 |
| Made ST Ltd | Wholesale & retail | 2020 |
| Maesa Aesthetics Clinic Ltd | Health & social care | 2025 |
| Magnettik Marketing Limited | Professional & scientific | 2020 |
| Mailbox Mania Limited | Wholesale & retail | 2007 |
| Mainsplan UK Limited | Construction | 2015 |
| Make Things Better Ltd | Professional & scientific | 2013 |
| Malcolm Rawes Orthopaedics Ltd | Health & social care | 2020 |
| Manor House Croft (Maintenance) Limited | Households | 1983 |
| Manson Properties Ltd | Real estate | 2022 |
| Manson(Uk) Ltd | Construction | 2015 |
| Manuka North Limited | Wholesale & retail | 2022 |
| MAP Transport Ltd | Transport & logistics | 2021 |
| Margot Flower Designs Ltd | Wholesale & retail | 2018 |
| Marigold Leisure Industries Limited | Hospitality | 2026 |
| Marketing Services (Yorkshire) Limited | Professional & scientific | 2010 |
| Marshall Commercial Services Limited | Professional & scientific | 2025 |
| Marshall Financial Planning Ltd | Professional & scientific | 2023 |
| Martin's Handy Help Ltd | Construction | 2026 |
| Marton Mills Company Limited | Manufacturing | 1931 |
| Mauré Studios Limited | Arts & recreation | 2024 |
| Maypole Fisheries Limited | Hospitality | 2010 |
| MB 1000 Unlimited | Financial services | 2018 |
| MB Heritage & Planning Limited | Professional & scientific | 2009 |
| MB True Ltd | Real estate | 2016 |
| Mckendrick Multimedia Limited | Administrative & support | 2009 |
| Mclernon Digital Limited | Information & communication | 2023 |
| MD Leonard's Ltd | Administrative & support | 2019 |
| Megatech Services Limited | Manufacturing | 1996 |
| Mendra Limited | Health & social care | 2025 |
| Menta Brand Ltd | Professional & scientific | 2023 |
| Merlin Wright Associates Ltd | Administrative & support | 2012 |
| Merrick Joinery Building Ltd | Construction | 2023 |
| Mfs&C Limited | Wholesale & retail | 2022 |
| MG Law Consultancy Ltd | Professional & scientific | 2022 |
| MGM Property Holdings Limited | Real estate | 2019 |
| MIA Nails Ltd | Other services | 2025 |
| Milestone Yorkshire Ltd | Administrative & support | 2025 |
| Mill DAM Consulting Limited | Information & communication | 2000 |
| Milner Window Cleaning Services Ltd | Administrative & support | 2021 |
| Milthorp Apartments Limited | Administrative & support | 2010 |
| Ministry of Faces Limited | Other services | 2022 |
| MJF Property (Yorkshire) Limited | Real estate | 2024 |
| MJL Groundworks & Civils Limited | Construction | 2020 |
| MK & SC Properties Limited | Real estate | 2022 |
| MK Franchise Limited | Education | 2025 |
| Modelsport Limited | Wholesale & retail | 2007 |
| Molly's Pet Pantry Ltd | Wholesale & retail | 2026 |
| Mortgage 365 Ltd | Financial services | 2024 |
| Moseley Ltd | Wholesale & retail | 2026 |
| Mossfold (Homes) Limited | Real estate | 1981 |
| Mountfield (Yorkshire Partnership) Limited | Real estate | 2025 |
| Mountfield Capital (Property) Limited | Real estate | 2023 |
| Movepro Limited | Professional & scientific | 2005 |
| MR Blinok Ltd | Hospitality | 2019 |
| MR Fishman Ltd | Hospitality | 2022 |
| MRS Beightons Sweet Shop Limited | Real estate | 2012 |
| MT Developments (Leeds) Ltd | Professional & scientific | 2016 |
| MT Trading Limited | Wholesale & retail | 2022 |
| Mundo MEP Limited | Professional & scientific | 2013 |
| MW Electrical Services (Yorkshire) Limited | Construction | 2009 |
| My Trade Force Ltd | Administrative & support | 2019 |
| Mycelium Consulting Limited | Information & communication | 2020 |
| N J Barton Consulting Ltd | Professional & scientific | 2015 |
| N L Motorhomes Yorkshire Ltd | Administrative & support | 2018 |
| Nailed IT - Horseshoe Nail Art Ltd | Arts & recreation | 2022 |
| Neate Homes Ltd | Construction | 2020 |
| Neil Stringwell Tarmacadam Ltd | Construction | 2005 |
| Nelbersie Properties Ltd | Construction | 2023 |
| New Oak Wealth Management Limited | Financial services | 2005 |
| New Skin Ltd | Other services | 2019 |
| New-Gen Storage Solutions Ltd | Other services | 2024 |
| Newall Hall (NO. 2) Limited | Households | 2019 |
| Newbould Yorkshire Limited | Construction | 2009 |
| Newboundaries Limited | Professional & scientific | 2016 |
| Newstead & Walker Holdings Limited | Financial services | 2025 |
| Newstead & Walker Limited | Professional & scientific | 2019 |
| Nicole Bowden Optics Limited | Health & social care | 2004 |
| Nigel Nelson Consulting Limited | Professional & scientific | 2022 |
| Nightingale First AID Training Ltd | Health & social care | 2014 |
| Niki Davies Productions Limited | Information & communication | 2005 |
| NIL Satis Nisi Optimum Limited | Administrative & support | 2012 |
| NMH Urology (Leeds) Limited | Real estate | 2015 |
| Nomads Wellness Club Ltd | Arts & recreation | 2025 |
| Noonstone Ltd | Transport & logistics | 2010 |
| Norco Ltd | Construction | 2020 |
| Nordoors (BFD) Limited | Real estate | 1982 |
| Norfolk and Chance Power Ltd | Administrative & support | 2025 |
| North for MEN Ltd | Other services | 2011 |
| Northconn Recruitment Limited | Administrative & support | 2013 |
| Northern Inc Ltd | Real estate | 2023 |
| Norwood Properties (JPF) Limited | Real estate | 2003 |
| Norwood Trading (West Yorkshire) Limited | Wholesale & retail | 1991 |
| Nosferatu Property Management Ltd | Real estate | 2020 |
| Novam Ltd | Professional & scientific | 2019 |
| NPA Associates Ltd | Professional & scientific | 2012 |
| Nutwell Legal Services Limited | Professional & scientific | 2025 |
| O R F Properties Ltd | Real estate | 2021 |
| Oak Wealth Ltd | Financial services | 2022 |