| Morley & Woodward Limited | Construction | 2011 |
| Morrison Media Limited | Professional & scientific | 2010 |
| Morvern Shipping Agency Limited | Professional & scientific | 1980 |
| Mosaic Futures Ltd | Professional & scientific | 2006 |
| Mototechnics Coalville Ltd | Wholesale & retail | 2024 |
| Mould Resources Ltd | Construction | 2009 |
| Moulton Farm Machinery Ltd | Manufacturing | 2016 |
| MP Car Solutions Ltd | Wholesale & retail | 2020 |
| MPA Property Developments Ltd | Real estate | 2016 |
| MR IT Services Ltd | Information & communication | 2016 |
| MR Mend Ltd | Construction | 2022 |
| MRC Community Action | Other services | 1996 |
| Mrprice Online ULC | Wholesale & retail | 2003 |
| MS Approaching Ltd | Transport & logistics | 2019 |
| Msapro Ltd | Construction | 2022 |
| MTR Trading Limited | Manufacturing | 2016 |
| Mtrevans Solutions Ltd | Manufacturing | 2014 |
| Muddy Paws VA Ltd | Administrative & support | 2024 |
| Mugga Hugga Ltd | Manufacturing | 2023 |
| Multiplier Consulting Limited | Other services | 2015 |
| Muscle HQ Ltd | Other services | 2014 |
| Muttshrooms Ltd | Wholesale & retail | 2024 |
| MVK Fire Limited | Administrative & support | 2026 |
| MW Land Services Ltd | Hospitality | 2020 |
| Mwair Manegment Ltd | Information & communication | 2025 |
| MWM Holdings Limited | Administrative & support | 2000 |
| My Budie Limited | Transport & logistics | 2025 |
| My Skinfood Ltd | Wholesale & retail | 2025 |
| Mystix Media Ltd | Information & communication | 2026 |
| N D Branston Ltd | Transport & logistics | 2022 |
| N Security Ltd | Administrative & support | 2024 |
| N&A Grill Ltd | Hospitality | 2023 |
| N.K.W Underwood Ltd | Hospitality | 2025 |
| N90 Autos Ltd | Wholesale & retail | 2025 |
| Nacional Safety Valves UK Limited | Wholesale & retail | 2020 |
| Nailook Ltd | Other services | 2023 |
| Naomi & Dany Transport Ltd | Transport & logistics | 2019 |
| Natalie Elizabeth Ltd | Wholesale & retail | 2026 |
| National Gaming Machines Ltd | Arts & recreation | 2021 |
| National Society of Master Thatchers Limited | Other services | 2003 |
| Natural Physique Ltd | Other services | 2024 |
| Navin Residence Ltd | Real estate | 2026 |
| NB Engines Solutions Ltd | Wholesale & retail | 2022 |
| NB Property Ltd | Real estate | 2025 |
| Ndebele Ltd | Wholesale & retail | 2024 |
| Needhams (Furnishers) Limited | Wholesale & retail | 1937 |
| Neesha Trading Limited | Wholesale & retail | 2010 |
| Neil D Jenkinson Consultancy Limited | Professional & scientific | 2019 |
| Nelson Electronics Ltd | Professional & scientific | 2026 |
| Nemean Ltd | Manufacturing | 2025 |
| Neolec Electrical and Construction Services Ltd | Construction | 2018 |
| Neptune Planning and Development Ltd | Construction | 2015 |
| Network Infrastructure and Computer Services Limited | Information & communication | 2009 |
| Neuroempowered Leicester CIC | Health & social care | 2025 |
| Neuue Build Ltd | Real estate | 2026 |
| Neuue Projects Limited | Real estate | 2022 |
| Neverland Property Services Ltd | Real estate | 2025 |
| New Cottage Poultry Ltd | Agriculture & fishing | 2024 |
| New MST Ltd | Transport & logistics | 2020 |
| Newland Lifestyle Ltd | Other services | 2017 |
| Newsome Services Ltd | Professional & scientific | 2025 |
| Next Level Innovations Limited | Arts & recreation | 2022 |
| NG Precision Engineering Limited | Professional & scientific | 2026 |
| NH Orme Heating Services Ltd | Construction | 2026 |
| NH Trading Limited | Administrative & support | 2026 |
| Nikhil Limited | Wholesale & retail | 2002 |
| Nikki's Brew & Bite Ltd | Hospitality | 2025 |
| Niko Management Ltd | Professional & scientific | 2024 |
| Nine Elms LLP | | 2013 |
| Nine Elms One Limited | Construction | 2016 |
| Nine Elms Two Limited | Construction | 2016 |
| Nitrous Nutrition Ltd | Wholesale & retail | 2025 |
| Nixsun Ltd | Financial services | 2020 |
| NJ Ventures (Leicester) Ltd | Financial services | 2024 |
| Njmidd Ltd | Hospitality | 2024 |
| NJR Electrical Services Ltd | Construction | 2017 |
| NJR Vision Ltd | Real estate | 2021 |
| NMC Cleaning Services Limited | Administrative & support | 2014 |
| NMC Digital Ltd | Information & communication | 2023 |
| NO Place Like Home Midlands Ltd | Public administration | 2020 |
| Noble Ents Limited | Arts & recreation | 2024 |
| Nomad Mangal Ltd | Hospitality | 2025 |
| Noonie and ME Ltd | Wholesale & retail | 2021 |
| Norfolk Garden Estates Limited | Construction | 1964 |
| North Gate CNC Limited | Wholesale & retail | 2023 |
| North West Land Developments Ltd | Administrative & support | 1996 |
| North West Leicestershire GP Limited | Health & social care | 2014 |
| Nottex Ltd | Wholesale & retail | 2013 |
| Nottingham Business Park (Orchard Place) Management Company Limited | Households | 2002 |
| Nottingham Business Park Management Company Limited | Households | 2002 |
| NPP Frozen Foods (Holdings) Limited | Financial services | 2019 |
| NPP Frozen Foods Limited | Wholesale & retail | 2001 |
| NS Engineering (Holdings) Limited | Professional & scientific | 2008 |
| NS Engineering Limited | Manufacturing | 1986 |
| Nskj Limited | Transport & logistics | 2012 |
| Nuesoft Limited | Information & communication | 2002 |
| NWL Cleaning Solutions Limited | Administrative & support | 2021 |
| NZT Group Limited | Professional & scientific | 2023 |
| O Hunt Crushing and Screening Ltd | Professional & scientific | 2024 |
| Oceanline Quality Ltd | Professional & scientific | 2026 |