| Mpre Services Ltd | Professional & scientific | 2016 |
| Mquitua Limited | Health & social care | 2015 |
| MR Lucker Ltd | Wholesale & retail | 2020 |
| Mrbgeneral Ltd | Professional & scientific | 2026 |
| MRD Property Ltd | Real estate | 2020 |
| MRJ Structural Design Ltd | Professional & scientific | 2015 |
| MS Progress Property Ltd | Real estate | 2025 |
| MSA Exhibitions Ltd | Other services | 2016 |
| Msdl Consulting Limited | Professional & scientific | 2022 |
| MSR Property Holdings Ltd | Real estate | 2023 |
| MSS Cousins Ltd | Other services | 2022 |
| MT Renovations Limited | Construction | 2015 |
| MTA Drilltec Limited | Construction | 2011 |
| Mudbeaters Limited | Construction | 2026 |
| Mudcontrol Limited | Construction | 2018 |
| Mulliner Holdings Limited | Financial services | 2022 |
| Multiroom Solutions Limited | Professional & scientific | 2024 |
| Mundal Properties Limited | Real estate | 1964 |
| Muniment Purley Limited | Real estate | 2019 |
| Muniment Titanium Developments Limited | Construction | 2018 |
| Muniment Ulverston Ltd | Construction | 2017 |
| Munster Training Limited | Professional & scientific | 2022 |
| Murie Surveying Ltd | Professional & scientific | 2026 |
| Murt Flanagan Limited | Real estate | 1972 |
| Muscle Finesse Limited | Wholesale & retail | 2006 |
| Muse Digital Limited | Professional & scientific | 2022 |
| Mushana GAS International Ltd | Energy | 2019 |
| Muzz Design Ltd | Administrative & support | 2007 |
| MV Hire Limited | Administrative & support | 2023 |
| MVK Transervice Ltd | Transport & logistics | 2024 |
| MVM Surveys Limited | Construction | 2002 |
| MVP Trading Ltd | Wholesale & retail | 2026 |
| MXI Limited | Other services | 2000 |
| My Little Vintage Ltd | Wholesale & retail | 2013 |
| My Property Pension Ltd | Financial services | 2021 |
| My Smart Consulting Limited | Professional & scientific | 2017 |
| Mygphonerepair Ltd | Wholesale & retail | 2025 |
| Mymaternalhub Ltd | Health & social care | 2025 |
| Myperfectwriting Limited | Professional & scientific | 2022 |
| Myshoal Ltd | Information & communication | 2015 |
| Mythicus Limited | Wholesale & retail | 2025 |
| MZX Driving Limited | Transport & logistics | 2012 |
| N & D Freight Ltd | Transport & logistics | 2017 |
| N & N International Amazon Ltd | Wholesale & retail | 2026 |
| N Arnett Ltd | Wholesale & retail | 2023 |
| N C Plastering Limited | Construction | 2021 |
| N Healey Transport Services Ltd | Transport & logistics | 2013 |
| N J Shaw Brickwork Limited | Construction | 2023 |
| N J Wills Plumbing & Heating Limited | Construction | 2024 |
| N R Groundworks Limited | Construction | 2003 |
| N R Plant Hire Limited | Administrative & support | 2016 |
| N Rodwell Properties Limited | Real estate | 2025 |
| N&A Tilling Ltd | Construction | 2015 |
| N&C Business Services Limited | Administrative & support | 2022 |
| N&D Courier Logistics Ltd | Transport & logistics | 2016 |
| N&T Rugare Limited | Transport & logistics | 2022 |
| N. Elmore Builders Limited | Construction | 2020 |
| N. RUE Ltd | Wholesale & retail | 2023 |
| N.C.Auto PDR Ltd | Wholesale & retail | 2025 |
| N.Jones Consultancy Ltd | Professional & scientific | 2026 |
| NA Private Limited | Wholesale & retail | 2026 |
| Naca Equipment Ltd | Wholesale & retail | 2025 |
| Nadean Group Ltd | Health & social care | 2022 |
| NAH Group Limited | Professional & scientific | 2005 |
| NAH Holdings Limited | Professional & scientific | 2007 |
| NAH Legal Services Limited | Other services | 2003 |
| NAH Support Services Limited | Professional & scientific | 1998 |
| Nahl Group PLC | Financial services | 2014 |
| Nahl Support Services Limited | Professional & scientific | 1993 |
| Naked Life Emea Limited | Manufacturing | 2024 |
| Nalamidam Media Initiative Ltd | Information & communication | 2024 |
| Nameless Studios Ltd | Wholesale & retail | 2025 |
| Namesake Promotions Limited | Information & communication | 1998 |
| Nanu Offices Limited | Administrative & support | 2022 |
| NAR Trading and Consulting Ltd | Wholesale & retail | 2022 |
| Narghiza Ltd | Health & social care | 2023 |
| Nashcee Limited | Health & social care | 2021 |
| Nastase Express Transport Ltd | Transport & logistics | 2025 |
| Nathan Willis Smart Repairs Limited | Wholesale & retail | 2013 |
| Nation@L Paper Recycling Limited | Administrative & support | 1995 |
| National Accident Helpline Limited | Extraterritorial | 1999 |
| National Accident Law Limited | Administrative & support | 2018 |
| National Conveyancing Partners Ltd | Professional & scientific | 2019 |
| National Legal Helpline LLP | | 2017 |
| Nationwide Handling Limited | Manufacturing | 2005 |
| Nationwide Maintenance Solutions Limited | Construction | 2013 |
| Natural Animal Nutrition Limited | Manufacturing | 2014 |
| Natural Intelligence Group Limited | Administrative & support | 2018 |
| Nature & YOU Ltd | Health & social care | 2021 |
| Natures Photos Ltd | Professional & scientific | 2009 |
| Naturopathic Practitioner Elena Siedin Ltd | Health & social care | 2021 |
| NAV Logistics Limited | Transport & logistics | 2022 |
| NAV Property Holdings Limited | Financial services | 2026 |
| NAV Van Hire Limited | Administrative & support | 2014 |
| NAV Van Property Co Limited | Real estate | 2026 |
| Navara OAT Milling Limited | Manufacturing | 2021 |
| Nbrg Associates Limited | Administrative & support | 2016 |
| NCH Logisticss Ltd | Construction | 2024 |
| ND Smile Clinic Ltd | Health & social care | 2024 |
| Ndaramo Limited | Manufacturing | 2020 |