| Mcsay Ltd | Wholesale & retail | 2019 |
| Meadow Road Limited | Construction | 2021 |
| Meadow Road Management Company Limited | Households | 2025 |
| Mediaatech (London) Ltd | Information & communication | 2023 |
| Medical Device Consulting (Behrooz Aghbosh) Limited | Administrative & support | 2017 |
| MEJ Solutions Ltd | Construction | 2025 |
| Melusine Lenoir Limited | Arts & recreation | 2015 |
| Metafora Solutions Limited | Information & communication | 2025 |
| Metalcraft Direct Ltd | Manufacturing | 2023 |
| Metro Estate Agents Ltd | Real estate | 2010 |
| MI & SON Traders Ltd | Wholesale & retail | 2020 |
| Microflo Scientific Limited | Professional & scientific | 2015 |
| Miklassic Ltd | Professional & scientific | 2016 |
| Milani Consultancy Ltd | Information & communication | 2016 |
| Mira Social Care Ltd | Health & social care | 2022 |
| MLM Accountant Ltd | Professional & scientific | 2020 |
| MMI Services Ltd | Transport & logistics | 2020 |
| MMI UK Investment Ltd | Real estate | 2024 |
| Mohan Real Estate Limited | Construction | 2020 |
| Mohney Investments Ltd | Financial services | 2021 |
| More Than Moore Ltd | Information & communication | 2022 |
| MS Property Group Limited | Real estate | 2018 |
| MT Group Ltd | Financial services | 2024 |
| Mumonet IT Services Limited | Information & communication | 2008 |
| My Little CUP Ltd | Wholesale & retail | 2019 |
| Mybee Ltd | Real estate | 2021 |
| MZ Service London Ltd | Hospitality | 2025 |
| N.Yacoub Ltd | Other services | 2023 |
| NA Trader Limited | Wholesale & retail | 2018 |
| Naibtech Industrial Services Ltd | Wholesale & retail | 2023 |
| Natural Skincare London Limited | Manufacturing | 2011 |
| Netcom Data Limited | Wholesale & retail | 2015 |
| Neuro Physio London Ltd | Health & social care | 2020 |
| Newedenway Limited | Professional & scientific | 2017 |
| Next Level Real Estate Ltd | Real estate | 2024 |
| Nexzell Solutions Ltd | Wholesale & retail | 2023 |
| NF Alpha 2 LLP | | 2015 |
| NF Alpha Ltd | Financial services | 2015 |
| Nightingale Films Limited | Information & communication | 1999 |
| Niveda Capital Ltd | Construction | 2017 |
| Niveda Group Ltd | Financial services | 2010 |
| Niveda Investments Limited | Financial services | 2011 |
| Niveda Realty Ltd | Construction | 2011 |
| NO Twenty Four Ltd | Administrative & support | 2015 |
| Nodal Ventures Ltd | Professional & scientific | 2026 |
| Nore Properties Limited | Real estate | 2021 |
| NR Andromeda Ltd | Construction | 2012 |
| NR Hercules 2 Ltd | Construction | 2017 |
| NR Hercules LLP | | 2017 |
| Octanos Capital Advisory Ltd | Financial services | 2019 |
| Ohrmazd Holdings Ltd | Financial services | 2021 |
| One Move Home Ltd | Real estate | 2017 |
| One Square Mile Consulting Ltd | Financial services | 2018 |
| Open Medical (KSA) Limited | Information & communication | 2025 |
| Open Medical (Qatar) Limited | Information & communication | 2025 |
| Open Medical (UAE) Limited | Information & communication | 2025 |
| OTP Agency Holdings Ltd | Real estate | 2019 |
| OTP Commercial Ltd | Real estate | 2020 |
| OTP Construction Management Limited | Construction | 2020 |
| OTP Group Holdings Limited | Financial services | 2018 |
| OTP Group Ltd | Real estate | 2018 |
| OTP Investments Limited | Real estate | 2017 |
| OTP Residential Ltd | Real estate | 2020 |
| Oxford Training Academy Ltd | Education | 2010 |
| P&A Ventures London Ltd | Wholesale & retail | 2025 |
| P.M.F. Systems Ltd | Administrative & support | 2012 |
| Park Royal Taxi Centre Limited | Manufacturing | 2002 |
| Parker Horizon Ltd | Financial services | 2025 |
| Parker Horizon Two Ltd | Real estate | 2025 |
| Parkway Computer Services Limited | Information & communication | 2003 |
| Pasta Remoli Group Limited | Administrative & support | 2020 |
| Pasta Remoli Production Ltd | Hospitality | 2015 |
| Pasta Remoli ST Pancras Ltd | Hospitality | 2015 |
| PAT Testing Services Ltd | Manufacturing | 2005 |
| Pathway Strategies Ltd | Financial services | 2023 |
| Patri Takeaway Limited | Hospitality | 2020 |
| Pavan Sagoo Limited | Arts & recreation | 2025 |
| PCL Lendco 1 LLP | | 2025 |
| Pdouble Four Limited | Households | 2025 |
| Pearson Business Solutions Limited | Professional & scientific | 2009 |
| Perfume Warehouse Limited | Wholesale & retail | 2004 |
| Pest Control Hampshire Ltd | Agriculture & fishing | 2014 |
| Pharmateam Ltd | Financial services | 2022 |
| Pink PIE Ltd | Wholesale & retail | 2022 |
| Polyvest Ltd | Real estate | 2023 |
| Porichoi Production Limited | Information & communication | 2012 |
| Povesti Ltd | Information & communication | 2021 |
| Powerfixx Limited | Construction | 2019 |
| PR Bromley Ltd | Hospitality | 2023 |
| PR Wembley Ltd | Hospitality | 2015 |
| PR Westfield Ltd | Manufacturing | 2015 |
| Premier Fire and Electrical Installations Limited | Construction | 2018 |
| Prescient Healthcare Group (UK) Limited | Professional & scientific | 1991 |
| Prescient Healthcare Group Limited | Professional & scientific | 1990 |
| Primewaycleaning Ltd | Administrative & support | 2025 |
| Prix Luxe Beauty Ltd | Wholesale & retail | 2020 |
| Projecco Ltd | Construction | 2025 |
| Project 1 Design & Build Limited | Construction | 2007 |
| Providus Capital Ltd | Real estate | 2019 |
| Public Sector Solutions (UK) Limited | Administrative & support | 2007 |