| Mukherjee Property Ltd | Real estate | 2020 |
| Multics Ltd | Information & communication | 2014 |
| Multiplay International Limited | Wholesale & retail | 2018 |
| Mums Cakes London Ltd | Manufacturing | 2020 |
| Munchies Food & Wine Ltd | Wholesale & retail | 2018 |
| Mundo-Mac Construction and Surfacing Ltd | Construction | 2018 |
| Mungazlogistics Ltd | Transport & logistics | 2018 |
| Mups Accountant Ltd | Professional & scientific | 2013 |
| Mups Development Limited | Real estate | 2022 |
| Murphybishop Ltd. | Education | 2021 |
| Murray 03 Ltd | Professional & scientific | 2003 |
| Murwalls Publishing Ltd | Arts & recreation | 2023 |
| Muscleflo WE Ltd | Wholesale & retail | 2023 |
| Muse Kapital Ltd | Administrative & support | 2014 |
| Music A&A Ltd | Arts & recreation | 2022 |
| Music and Arts Vision Ltd | Education | 2025 |
| Musmel Ltd | Hospitality | 2019 |
| Muswell Capital Limited | Professional & scientific | 2023 |
| MV Pipe Work Ltd | Construction | 2012 |
| MV Properties Cambridge Limited | Real estate | 2020 |
| MW Cabling Services Ltd | Construction | 2023 |
| MW Photography Limited | Professional & scientific | 2013 |
| MW Properties NO 22 Limited | Professional & scientific | 2005 |
| Mwafrika Healthcare Ltd | Administrative & support | 2015 |
| MX Builders Ltd | Construction | 2019 |
| MXM Electrical Ltd | Construction | 2025 |
| My Big Green Fleet Ltd | Transport & logistics | 2014 |
| My Bureau Ltd | Real estate | 2020 |
| My Digital Bricks Limited | Information & communication | 2020 |
| My Housekeeper Limited | Administrative & support | 2025 |
| My Key Accountants Ltd | Professional & scientific | 2019 |
| My London Property Ltd | Real estate | 2020 |
| My Response Team Limited | Administrative & support | 2018 |
| MYA & Olive UK Ltd | Wholesale & retail | 2022 |
| Myct Ltd | Health & social care | 2025 |
| Mydadssuitcase Ltd | Wholesale & retail | 2023 |
| Myes Group Ltd | Wholesale & retail | 2021 |
| Myia Productions Ltd | Information & communication | 2025 |
| Myke Accountants Ltd | Professional & scientific | 2022 |
| Myles Court Management Co. Limited | Households | 1991 |
| Myles Jenkins Ltd | Administrative & support | 2014 |
| Myogenes Limited | Health & social care | 2016 |
| Mystgem Limited | Wholesale & retail | 2025 |
| MZ Bishop Limited | Real estate | 2026 |
| MZ CL Limited | Health & social care | 2021 |
| MZ Fifty Nine Limited | Real estate | 2026 |
| MZ Medical Limited | Health & social care | 2012 |
| MZ Skin Limited | Other services | 2015 |
| Mzee Management Consultancy Ltd | Professional & scientific | 2022 |
| MZL 129 Camden Limited | Real estate | 2026 |
| MZL 84 Camden Limited | Real estate | 2026 |
| N & C Building Services Ltd | Construction | 2018 |
| N B Solutions Services Limited | Construction | 2016 |
| N D Aviation Ltd | Manufacturing | 2014 |
| N Damani Limited | Health & social care | 2003 |
| N Ebrahim Ltd | Education | 2020 |
| N P Daniels Services Ltd | Construction | 2021 |
| N T Laser Limited | Other services | 2015 |
| N Terry Electrical Contractors Limited | Construction | 2002 |
| N Wellness Solutions Ltd | Wholesale & retail | 2019 |
| N&A Consultants Ltd | Professional & scientific | 2023 |
| N&B Contractors Ltd | Construction | 2023 |
| N-Beta Limited | Professional & scientific | 2006 |
| N.A Aesthetics Ltd | Other services | 2020 |
| N10 Developments Ltd | Real estate | 2022 |
| N11 Design Limited | Administrative & support | 2010 |
| N16 Rentals Limited | Real estate | 2018 |
| Nabeeha Limited | Real estate | 2016 |
| Nadel Medical Ltd | Health & social care | 2009 |
| NAF NAF Trade Limited | Wholesale & retail | 2021 |
| Naijeriya Limited | Financial services | 2023 |
| Nail Avenue Ltd | Other services | 2023 |
| Nails & Brows Limited | Administrative & support | 2013 |
| Naji Consulting Ltd | Education | 2023 |
| Nali Recovery Ltd | Transport & logistics | 2025 |
| NAM: DM (NO 1) Ltd | Real estate | 2021 |
| Namara Film Productions Ltd | Arts & recreation | 1974 |
| Namdro Enterprises Limited | Information & communication | 1999 |
| Namh Ltd | Real estate | 2021 |
| Nano Optical Sensor Equipment Solutions Ltd | Administrative & support | 2013 |
| Nanomab Technology (UK) Limited | Professional & scientific | 2020 |
| Nanosense Limited | Financial services | 2024 |
| Nanothera Limited | Administrative & support | 2025 |
| Naomi Property Management Ltd | Real estate | 2025 |
| Napsbury Park Estate Management Company Limited | Households | 2016 |
| Narborough House Properties Ltd | Real estate | 2026 |
| Nas&Son Ltd | Transport & logistics | 2023 |
| Nasaya Holdings Ltd | Real estate | 2025 |
| Nascot Court Limited | Households | 1999 |
| Nasty Vegan Limited | Manufacturing | 2019 |
| Natali Kelly Limited | Health & social care | 2009 |
| Natalovi Ltd | Wholesale & retail | 2016 |
| Nataral Ltd | Wholesale & retail | 2016 |
| National Fitness and Leisure Group Limited | Arts & recreation | 2020 |
| National Rock Supplies Ltd | Construction | 2022 |
| Nationwide Cctv Services (Norfolk) Limited | Administrative & support | 2015 |
| Nationwide Cctv Services Limited | Administrative & support | 2006 |
| Nationwide Security Limited | Administrative & support | 2011 |
| Natmark Distribution Ltd | Wholesale & retail | 2015 |
| Natpath Ltd | Health & social care | 2008 |