| Mrkt Property Experts Limited | Real estate | 2018 |
| Mrkt Property Holdings Limited | Financial services | 2024 |
| Mrpm Direct Ltd | Wholesale & retail | 2022 |
| Mrsu Construction Ltd | Construction | 2025 |
| MS Murphy P&D Ltd | Construction | 2022 |
| MS Prop Developments Ltd | Real estate | 2021 |
| MSL23 Limited | Construction | 2024 |
| MSP Systems Limited | Information & communication | 2005 |
| MSU Ltd | Construction | 2021 |
| MT Nest Property Ltd | Real estate | 2024 |
| MTE Square Ltd | Professional & scientific | 2020 |
| MTI Haulage Limited | Transport & logistics | 2024 |
| MTM Properties Group Limited | Real estate | 2019 |
| MTM35 Ltd | Transport & logistics | 2022 |
| MTN Plant Limited | Manufacturing | 2019 |
| Mttc Transport Ltd | Wholesale & retail | 2023 |
| MTZ Haulage Limited | Transport & logistics | 2025 |
| Mubarak Valeting Group Ltd | Extraterritorial | 2022 |
| Mudoc Transport Ltd | Transport & logistics | 2025 |
| Mujaeds Management Group Ltd | Real estate | 2022 |
| Mumtaz Designs & Associates Limited | Professional & scientific | 2012 |
| Murad Consultancy Ltd | Health & social care | 2024 |
| Murray Plasterers Limited | Construction | 2025 |
| Murray's Electrical Ltd | Construction | 2021 |
| MUS 49 Limited | Other services | 2024 |
| Muva Gurus Limited | Real estate | 2017 |
| Muva Property Gurus BH Limited | Real estate | 2019 |
| Muva Property Gurus Limited | Real estate | 2017 |
| Muva Technologies Limited | Real estate | 2017 |
| MUX Services Ltd | Information & communication | 2019 |
| MV JET Wash Ltd | Administrative & support | 2024 |
| MV Printing Ltd | Manufacturing | 2018 |
| MVG 92 Limited | Administrative & support | 2022 |
| MWA Holdings Aylesbury Ltd | Real estate | 2024 |
| MWA Investments Limited | Real estate | 2019 |
| My Cabbie Ltd | Transport & logistics | 2020 |
| My E-Store Ltd | Wholesale & retail | 2022 |
| My Hospitality Systems Limited | Information & communication | 2019 |
| My Property Repair Limited | Construction | 2025 |
| My Roof Ltd | Construction | 2020 |
| Mybellamy Massage and Beauty Ltd | Other services | 2024 |
| Mynek Group Limited | Manufacturing | 2025 |
| Mynest Logistics Ltd | Transport & logistics | 2025 |
| Mynott Associates Limited | Professional & scientific | 2016 |
| Mynott Bowers Group Limited | Professional & scientific | 2022 |
| Mynott Bowers Limited | Professional & scientific | 2022 |
| Myolab LLP | | 2025 |
| Mythax Ltd | Manufacturing | 2025 |
| N Property Limited | Real estate | 2017 |
| N.A.M. Carpentry Limited | Construction | 1996 |
| N.K Bathroom & Plumbing Ltd | Wholesale & retail | 2015 |
| N.K Bhanot Properties Ltd | Real estate | 2025 |
| Nabe Cares Limited | Health & social care | 2020 |
| Naellevin Care Limited | Health & social care | 2023 |
| Naellevin Property Group Ltd | Real estate | 2024 |
| Nagi Consultants Limited | Professional & scientific | 2012 |
| Nagi Property Investments Ltd | Real estate | 2020 |
| Nahar's Kitchen Ltd | Hospitality | 2025 |
| Nairpic Ltd | Construction | 2015 |
| Najam Ltd | Wholesale & retail | 2024 |
| Napier UK Property Ltd | Real estate | 2020 |
| Napolean Ltd | Other services | 2022 |
| Nathanoak Limited | Information & communication | 2026 |
| National Glass Polishers Limited | Construction | 2021 |
| National Gulf View Ltd | Construction | 2024 |
| Native Tallow Limited | Wholesale & retail | 2022 |
| Natt Recruitment Consultants UK Ltd | Administrative & support | 2025 |
| Natural by Nature Oils Limited | Wholesale & retail | 1985 |
| Nature Peak Coaching Limited | Other services | 2026 |
| Naturmix Ltd | Wholesale & retail | 2023 |
| Navexa Ltd | Information & communication | 2025 |
| Nawab Ryan Ltd | Other services | 2026 |
| Nawazai Suites Ltd | Real estate | 2024 |
| Naxy Ltd | Transport & logistics | 2022 |
| Nayara Ltd | Arts & recreation | 2022 |
| Nayara Properties Ltd | Real estate | 2023 |
| NCC Professional Limited | Real estate | 2008 |
| Nd.Dw.Cb Ltd. | Other services | 2004 |
| NDD Properties Limited | Real estate | 2025 |
| NEC Communications Ltd | Information & communication | 2007 |
| Neil Munro Associates Limited | Construction | 1988 |
| Neil Shadbolt Tree Surgery Limited | Agriculture & fishing | 2002 |
| Nellyd Limited | Manufacturing | 2017 |
| Nemesis Transport Limited | Administrative & support | 2006 |
| Nenneh Jalloh Ltd | Health & social care | 2013 |
| Neon Bites Limited | Hospitality | 2024 |
| Nepti - Waste Disposal Ltd | Water & waste | 2019 |
| NET Cars 2 YOU Limited | Wholesale & retail | 2017 |
| Netvista Solutions Limited | Information & communication | 2006 |
| Networked City Ltd | Information & communication | 2019 |
| Neurorise Coaching Ltd | Health & social care | 2025 |
| Nevil Food and Wine Limited | Wholesale & retail | 2015 |
| Nevitt Holdings Ltd | Real estate | 2024 |
| Nevitt Properties Ltd | Real estate | 2022 |
| Nevs Property Ltd | Real estate | 2022 |
| New Apostolate Authentic Church International Ltd | Other services | 2026 |
| New Clapton Stadium Company Limited | Professional & scientific | 1964 |
| New Curry Lounge Limited | Hospitality | 2026 |
| New Generation Entertainment Limited | Other services | 2013 |
| New Mercia Hitchin Management Limited | Households | 2007 |