| My JOB Matcher Limited | Administrative & support | 2011 |
| My Little Stars Cambridge Ltd | Health & social care | 2025 |
| My Mini Display Ltd | Wholesale & retail | 2023 |
| My Own DEN Limited | Professional & scientific | 2014 |
| My Race Hub Ltd | Information & communication | 2026 |
| My Repreview Co., Ltd | Other services | 2021 |
| My Sine Ltd | Professional & scientific | 2024 |
| My SPP Limited | Transport & logistics | 2018 |
| My Stay Maintenance & Cleaning Limited | Administrative & support | 2025 |
| My Time Fine Fare Ltd | Hospitality | 2015 |
| My Village Handyman Limited | Construction | 2016 |
| My-Tyme Legacy Club Limited | Other services | 1996 |
| MYA Chiropractic Ltd | Health & social care | 2019 |
| Mycount Limited | Professional & scientific | 2018 |
| Mydvin Beauty Ltd. | Wholesale & retail | 2024 |
| Myfloss Limited | Wholesale & retail | 2026 |
| Myhill's Minibuses Ltd | Transport & logistics | 2009 |
| Mykogo Ltd | Manufacturing | 2025 |
| Mynah Partners Ltd | Professional & scientific | 2019 |
| Myonlineclinic Limited | Administrative & support | 2017 |
| Myproteus Holdings Limited | Administrative & support | 2010 |
| Myproteus Limited | Administrative & support | 2010 |
| Myriad QXP Limited | Professional & scientific | 2022 |
| Myrtle Software Limited | Information & communication | 2003 |
| Myrtleside (Northwood) Company Limited (the) | Households | 1970 |
| Mythic Beasts Limited | Information & communication | 2000 |
| Mythica Entertainment Limited | Information & communication | 2013 |
| Mythicsoft Limited | Information & communication | 2004 |
| Mytrax Media Limited | Information & communication | 2022 |
| Mzungu Aviation Ltd | Manufacturing | 2024 |
| Møller Institute Limited | Hospitality | 1992 |
| N & a Developers Ltd | Real estate | 2026 |
| N & a Wright Property Ltd | Administrative & support | 2017 |
| N & C Assets Limited | Financial services | 2025 |
| N & M Wholesale Ltd | Wholesale & retail | 2017 |
| N &Z Consultancy Services Ltd | Information & communication | 2011 |
| N and Z Packaging Ltd | Extraterritorial | 2020 |
| N B Composite Services Limited | Manufacturing | 2019 |
| N Burrows Holdings Ltd | Financial services | 2025 |
| N C T R Ltd. | Professional & scientific | 2008 |
| N Desai Limited | Professional & scientific | 2017 |
| N Durning Construction Limited | Construction | 2021 |
| N E Joinery Limited | Manufacturing | 2003 |
| N G Futures Ltd | Financial services | 2011 |
| N P Garner & SON Limited | Agriculture & fishing | 2012 |
| N&A Enterprises Limited | Real estate | 2024 |
| N&T Business Services Ltd | Professional & scientific | 2022 |
| N&Th Limited | Health & social care | 2025 |
| N-Sim Limited | Information & communication | 2005 |
| N. Freelance Programming Limited | Information & communication | 2007 |
| N.A.P Composites Ltd | Manufacturing | 2018 |
| N.V.A. Limited | Administrative & support | 1992 |
| N3WWW Ltd | Professional & scientific | 2022 |
| N8 Talent Ltd | Administrative & support | 2023 |
| Na/Films Limited | Professional & scientific | 2007 |
| NA3 Amrutham Ltd | Hospitality | 2024 |
| NAANIG8 Multi Sleek Solutions Limited | Transport & logistics | 2025 |
| Naar Aero Ltd | Manufacturing | 2023 |
| Nacicu Ltd | Manufacturing | 2023 |
| Nadia's Bakehouse Ltd | Manufacturing | 2026 |
| Nadin Limited | Professional & scientific | 2023 |
| Naftel Aerospace Limited | Manufacturing | 2021 |
| Naftel Engineering Ltd | Manufacturing | 2025 |
| Nagadev Limited | Health & social care | 2021 |
| NAI LOK Co., Ltd | Extraterritorial | 2014 |
| Nairam Ertep Ltd | Manufacturing | 2025 |
| Naitive Technologies Limited | Information & communication | 2018 |
| Najd Stud Limited | Agriculture & fishing | 2020 |
| Naked Clam Ltd | Agriculture & fishing | 2023 |
| Nakia Accounting Services Ltd | Professional & scientific | 2021 |
| Nalm Limited | Professional & scientific | 2018 |
| Namarc Consulting Ltd | Information & communication | 2026 |
| Namas Technologies Limited | Professional & scientific | 2014 |
| Namaste Cambridge Ltd | Hospitality | 2019 |
| Namaste Mart Ltd | Wholesale & retail | 2024 |
| Namei Garment Accessories Co., Ltd | Extraterritorial | 2015 |
| Namene Service Company Limited | Professional & scientific | 2017 |
| Namene Solar Lights Limited | Manufacturing | 2018 |
| Namene Working Capital Limited | Financial services | 2019 |
| Namjag Barwa Ltd | Extraterritorial | 2014 |
| Namysto | Information & communication | 2022 |
| Nandi Trading Company Limited | Wholesale & retail | 2023 |
| Nandia UK Limited | Manufacturing | 2023 |
| Nandor Solutions Ltd. | Construction | 2017 |
| Nane Trans Ltd | Transport & logistics | 2026 |
| Nanjing 3C Chemical Co., Ltd | Extraterritorial | 2018 |
| Nanjing Shandy International Co., Ltd | Wholesale & retail | 2014 |
| Nankibai Ltd | Financial services | 2026 |
| Nannakola Ltd | Agriculture & fishing | 2025 |
| Nanoarc Materials Ltd | Professional & scientific | 2025 |
| Nanobeam Limited | Manufacturing | 2001 |
| Nanoglow Energy Limited | Energy | 2025 |
| Nanoma Limited | Construction | 2025 |
| Nanoplume Ltd | Professional & scientific | 2024 |
| Naoma Enterprises Limited | Professional & scientific | 2018 |
| Napoleat Catering Ltd | Hospitality | 2025 |
| Napoleat Ltd | Hospitality | 2022 |
| Napp Laboratories Limited | Wholesale & retail | 1923 |
| Napp Pension Trustees Limited | Professional & scientific | 2012 |
| Napp Pharmaceutical Group Limited | Manufacturing | 1966 |