| Miller’S Bar & Grill Ltd | Hospitality | 2019 |
| Milner Holdings (Matlock) Ltd | Financial services | 2014 |
| Mineral Products Qualifications Council | Mining & quarrying | 1983 |
| MJA Contracting Ltd | Professional & scientific | 2024 |
| MJH Engineering Services (Midlands) Limited | Construction | 2010 |
| MJH Surveying Limited | Construction | 2024 |
| Mkac Property Ltd | Real estate | 2024 |
| MKT Catering Group Ltd | Administrative & support | 2019 |
| Mobile Screenwipe Limited | Wholesale & retail | 2007 |
| Moca Bar Limited | Hospitality | 2011 |
| Modern Estate Developments Limited | Real estate | 2020 |
| Moksha Holistic Therapies CIC | Health & social care | 2025 |
| Molyneux Business Park Management Company Limited | Real estate | 2023 |
| Mood. Reformer Studios Limited | Arts & recreation | 2026 |
| Moog Estates Ltd | Real estate | 2025 |
| Moorlands Leisure Limited | Real estate | 2025 |
| Moot 4 X 4 Limited | Wholesale & retail | 2023 |
| Moran Medical Ltd | Health & social care | 2024 |
| Morgan Independent Financial Services Limited | Financial services | 2003 |
| Morledge Management Company Limited | Households | 2015 |
| Mothax Limited | Information & communication | 2012 |
| Motion Concepts Limited | Professional & scientific | 2015 |
| Motoriginals Limited | Wholesale & retail | 2024 |
| Moylan Electrical Limited | Construction | 2011 |
| MPC Property Holdings Ltd | Real estate | 2018 |
| MR + MRS D a Cooper Properties Ltd | Real estate | 2019 |
| MT Family Therapy Ltd | Health & social care | 2026 |
| Mucky Ducks Limited | Administrative & support | 2020 |
| Muffle Limited | Wholesale & retail | 2018 |
| Mullaney Heights Limited | Hospitality | 2025 |
| Multifil Limited | Professional & scientific | 1991 |
| Musicbycandlelight Ltd | Arts & recreation | 2023 |
| Musicwirks CIC | Arts & recreation | 2022 |
| My Handmade Jewellery Ltd | Wholesale & retail | 2025 |
| My Own Door Community Interest Company | Other services | 2021 |
| My Own Door Supported Living Ltd | Administrative & support | 2023 |
| Mylily Capital Ltd | Professional & scientific | 2018 |
| Mylily Holdings Ltd | Financial services | 2017 |
| Mylittlewonders Ltd | Health & social care | 2022 |
| N Jenkins & Sons Ltd | Construction | 2016 |
| N Slowen Exports Ltd | Wholesale & retail | 2022 |
| N.E.W. Accountancy Services Limited | Professional & scientific | 2001 |
| N66 Ltd | Construction | 2016 |
| National Stone Centre(The) | Information & communication | 1984 |
| Natural Stone Fixing Limited | Extraterritorial | 2003 |
| Naturesound Ltd | Professional & scientific | 2024 |
| New Canton Cuisine Ltd | Hospitality | 2024 |
| New Spice Matlock Ltd | Hospitality | 2025 |
| Next Generation Heat Limited | Construction | 2008 |
| Next LAP UK Limited | Wholesale & retail | 2026 |
| Nibbles & Nosh Limited | Hospitality | 2003 |
| Nibrotech Ltd | Professional & scientific | 2020 |
| Nicholas Properties Limited | Real estate | 1997 |
| Nightingale Bikes Limited | Wholesale & retail | 2016 |
| Niven & Joshua Ltd | Wholesale & retail | 2007 |
| Niventa Holdings Limited | Real estate | 2002 |
| Niventa Limited | Real estate | 2002 |
| Nixer Designs Limited | Professional & scientific | 2022 |
| Nixon Haulage Contractors Limited | Transport & logistics | 2020 |
| NJD Music Limited | Education | 2016 |
| NLH Finishing Ltd | Construction | 2017 |
| NO.5 Dining Ltd | Hospitality | 2025 |
| North Fencing Ltd | Agriculture & fishing | 2017 |
| Northern Training Academy Limited | Education | 2015 |
| Northern Vintage Limited | Wholesale & retail | 2013 |
| Northpark Farm (Darleydale) Ltd | Agriculture & fishing | 2021 |
| NOT for Profit Consultants Limited | Professional & scientific | 2025 |
| NRB Electrical Limited | Professional & scientific | 2009 |
| NSC Go Limited | Hospitality | 2017 |
| Nsjt Developments Limited | Real estate | 2003 |
| Nugent Printing Solutions Ltd | Manufacturing | 2024 |
| Numberhawk Ltd | Professional & scientific | 2020 |
| NX Technology Ltd | Information & communication | 2018 |
| O Connor Arboriculture Limited | Agriculture & fishing | 2025 |
| O.B. Cruise Developments Ltd | Real estate | 2025 |
| Oak Tree Funeral Celebrants Limited | Other services | 2026 |
| Oakenstone Design Ltd | Construction | 2013 |
| Oakenstone Developments Ltd | Construction | 2013 |
| Oakenstone Ecobuild Ltd | Construction | 2022 |
| Oaker Consulting Ltd | Professional & scientific | 2012 |
| Oakleigh Homes 2013 Limited | Construction | 2013 |
| Oaksedge Farm Dog Hotel Limited | Hospitality | 2019 |
| Oakview Fencing Ltd | Construction | 2018 |
| Oakview Landscaping Ltd | Administrative & support | 2015 |
| Oakwood Drive Management Company Limited | Real estate | 1999 |
| OBT Investment Limited | Real estate | 2022 |
| Occsafe Services Limited | Other services | 2009 |
| Oddsocks Communications Limited | Arts & recreation | 2011 |
| Ogston View Residents Management Company Limited | Households | 2024 |
| OH LA DE DAH Ltd | Professional & scientific | 2016 |
| Oker Travel Ltd | Transport & logistics | 2016 |
| Old Angel Limited | Hospitality | 2016 |
| Old Oak Close Limited | Construction | 2026 |
| Oldfield Operational Services Limited | Administrative & support | 2017 |
| Oliver's Decorating Ltd | Construction | 2019 |
| Ollie Mart Building Services Ltd | Construction | 2024 |
| Once-A-Week Quarry Limited | Extraterritorial | 2011 |
| One Step Ahead Enterprises Limited | Arts & recreation | 2026 |
| Ongrel Holdings Limited | Professional & scientific | 2015 |
| Ophthalmic Vision Care Ltd | Health & social care | 2023 |