| Mojoboxes Ltd | Wholesale & retail | 2025 |
| Mokyklele Pupa Limited | Education | 2020 |
| Molo Homes Ltd | Real estate | 2020 |
| Monastiraki Ltd | Hospitality | 2019 |
| Mondopro & Co Ltd | Construction | 2014 |
| Moniks Limited | Construction | 2007 |
| Morelli Ices - Sutton Ltd | Hospitality | 2025 |
| Morelli Ices - Wimbledon Ltd | Hospitality | 2025 |
| Morgans CA Limited | Professional & scientific | 2002 |
| MORRIS2 Retail Ltd | Wholesale & retail | 2025 |
| Morrowmoss Studios Ltd | Information & communication | 2026 |
| Mould LAB Ltd | Professional & scientific | 2021 |
| Mount Park Limited | Professional & scientific | 2015 |
| MPM Lifts Ltd | Manufacturing | 2021 |
| MRD Foods Limited | Hospitality | 2023 |
| MRG Assist Ltd | Real estate | 2013 |
| Msquare Holding Limited | Information & communication | 2021 |
| MTA Properties Ltd | Real estate | 2025 |
| MTB Quality Painting & Decorating Services Limited | Construction | 2021 |
| MTE Power Ltd | Professional & scientific | 2024 |
| Mugils Consulting Ltd | Information & communication | 2023 |
| Muhar Properties Ltd | Real estate | 2026 |
| Multiverse Traders Ltd | Wholesale & retail | 2025 |
| Muneer Fruit & VEG Ltd | Wholesale & retail | 2019 |
| Murphs Services Ltd | Administrative & support | 2022 |
| Murtagh Construction Services Ltd | Construction | 2018 |
| Musuwo Fresh Farm Produce Ltd | Agriculture & fishing | 2026 |
| MW Building and Landscapes Limited | Construction | 2015 |
| MWB Dance Ltd | Arts & recreation | 2023 |
| My House Solutions Ltd | Construction | 2020 |
| My Inventory Clerk Ltd | Households | 2022 |
| Myla Engineering Ltd | Construction | 2024 |
| Mymedfolio Ltd | Information & communication | 2026 |
| Mypurecore Ltd | Wholesale & retail | 2017 |
| Myteeth Dental Ltd | Health & social care | 2019 |
| N Bala and Sons Ltd | Wholesale & retail | 2023 |
| N Construction Limited | Construction | 2014 |
| N K S Properties Investments Limited | Real estate | 2017 |
| N&S Electrical Services Ltd | Manufacturing | 2015 |
| N&S Retailers UK Ltd | Wholesale & retail | 2019 |
| Naamsu Limited | Real estate | 2019 |
| Nacho OP Ltd | Construction | 2022 |
| Naira Consultants Ltd | Professional & scientific | 2023 |
| Nama Trading Ltd | Wholesale & retail | 2020 |
| Namq Home Ltd | Real estate | 2025 |
| Naqshband Islamic Centre Ltd | Other services | 2016 |
| Natural Environmental Protection Forum | Health & social care | 2015 |
| Natural Resources Consulting Limited | Professional & scientific | 2022 |
| Navystone Ltd | Households | 2020 |
| ND & PH Group Limited | Households | 2025 |
| Neal's Services Limited | Manufacturing | 2023 |
| Nebo & Restoration Ltd | Health & social care | 2019 |
| Nehru & Son's Ltd | Wholesale & retail | 2023 |
| Nehru & Son's Property Ltd | Real estate | 2025 |
| Neighborhood Builders Ltd | Construction | 2025 |
| Neil Hardy Aquatica Limited | Agriculture & fishing | 1982 |
| Nepali Investment Limited | Other services | 2023 |
| Neron 82 Limited | Construction | 2015 |
| Nest Quest Limited | Real estate | 2023 |
| Net-Progress Limited | Information & communication | 2017 |
| Netcrown Limited | Other services | 2017 |
| Nevaal Services Ltd | Professional & scientific | 2026 |
| Never Speechless Ltd | Professional & scientific | 2023 |
| New Chapter Legacy CIC | Health & social care | 2026 |
| New Shanghai Pearl Limited | Hospitality | 2014 |
| Neway Energy Ltd | Administrative & support | 2014 |
| Newlive Ltd | Construction | 2016 |
| Next GEN Connect CIC | Education | 2024 |
| Next Phase Limited Ltd | Construction | 2026 |
| Next-Gen Electronic Ltd | Wholesale & retail | 2013 |
| Nextphase Contractors Ltd | Construction | 2025 |
| NHW Properties Limited | Real estate | 2025 |
| NIC Naks Snacks Ltd | Hospitality | 2025 |
| Nick's Bespoke Construction Ltd | Construction | 2021 |
| Nickel Support Community Interest Company | Health & social care | 2012 |
| Nicola Miles Limited | Other services | 2017 |
| Nienaber & Marais Ltd. | Hospitality | 2014 |
| Nigel Carpenter & Company Ltd. | Hospitality | 2018 |
| Nightingale Studio Ltd | Health & social care | 2016 |
| Nihao Mandarin Language School Ltd | Education | 2007 |
| NIK Someheart Ltd | Financial services | 2026 |
| Nikom Service Limited | Other services | 2014 |
| Niruthil Property Management Ltd | Real estate | 2024 |
| Nisrine Services Limited | Hospitality | 2025 |
| Nivaas Properties Ltd | Real estate | 2026 |
| NJR Barbers Limited | Other services | 2003 |
| NK Services (2014) Limited | Construction | 2014 |
| NLB Limited | Construction | 2021 |
| Nltdigitalart & Designs Ltd | Arts & recreation | 2024 |
| NM Ventures Ltd | Real estate | 2016 |
| NMI Ltd | Construction | 2025 |
| NMR Brands (UK) Limited | Wholesale & retail | 2021 |
| NMS Khan Properties Ltd | Real estate | 2024 |
| Nncp Limited | Real estate | 2025 |
| Nnsa Properties Ltd | Real estate | 2020 |
| NO. 16 UK Ltd | Real estate | 2025 |
| NO.3 Beauty Lodge Limited | Other services | 2024 |
| Noble Art Bureau Limited | Administrative & support | 2026 |
| North American Aviation Group UK Ltd | Administrative & support | 2013 |
| NOT Naturally Corporate Ltd | Professional & scientific | 2025 |