| MBG Residents Management Company Limited | Households | 2025 |
| Mcalex Services Ltd | Administrative & support | 2021 |
| Mcfarland Arrochar Ltd | Agriculture & fishing | 2023 |
| Mckenna Limited | Transport & logistics | 2001 |
| Mcqtech Ltd | Information & communication | 2010 |
| MDB Business Services Limited | Administrative & support | 2025 |
| Mdpharm Consulting Limited | Professional & scientific | 2024 |
| Meadow View (Houghton LE Spring) Residents Management Company Limited | Households | 2019 |
| MEB Cooke Limited | Information & communication | 2013 |
| MEB Golf Limited | Arts & recreation | 2026 |
| Media Catalyst Limited | Information & communication | 2020 |
| Medicare OS Ltd | Administrative & support | 2016 |
| Mediled Consulting Limited | Professional & scientific | 2025 |
| Meikle Polo Ltd | Arts & recreation | 2024 |
| Melanie Ayre Limited | Professional & scientific | 2018 |
| Merlin Plant Training Limited | Construction | 2021 |
| Mersey Film Limited | Extraterritorial | 2003 |
| Metjquality Ltd | Professional & scientific | 2024 |
| MGC Aerospace Limited | Professional & scientific | 2018 |
| Michec Engineering Ltd | Professional & scientific | 2018 |
| Midland Road (Royston) Management Company Limited | Households | 2018 |
| Milby Meadows Management Company Limited | Households | 2024 |
| Mill Fields (Wingerworth) Management Company Limited | Real estate | 2021 |
| Mill Green Meadows Residents Management Company Limited | Households | 2025 |
| Miller Transport (Chester) Ltd | Transport & logistics | 2005 |
| Millionari Ltd | Other services | 2010 |
| Millstone Park Residents Management Company Limited | Households | 2022 |
| Mimentor Limited | Information & communication | 2024 |
| Minchin Property Group Limited | Professional & scientific | 2020 |
| Minshull Oak Ltd | Other services | 1997 |
| Miracle View Ltd | Health & social care | 2022 |
| Miwellbeing Limited | Health & social care | 2024 |
| Mixsingh Records Ltd | Information & communication | 2021 |
| MJF Groundworks Limited | Construction | 2014 |
| ML Wells Limited | Real estate | 2006 |
| Modern Haus Group Ltd | Construction | 2016 |
| Molly MOP Cleaning Ltd | Administrative & support | 2009 |
| Monarchy Hall Farm Management Company Limited | Households | 2021 |
| Mondrem Green Management Company Limited | Households | 2012 |
| Moreney Investments Limited | Financial services | 1992 |
| Morley Green Properties Ltd | Real estate | 2019 |
| Morris and Sons Estates Ltd | Real estate | 2023 |
| Mortimer Park Phase 2 and Porters Way Residential Management Company Limited | Households | 2024 |
| Motion Consultancy Limited | Wholesale & retail | 2024 |
| Mount Park (Springwell) Residents Management Company Limited | Households | 2022 |
| Mount Pleasant Property Co. Ltd | Real estate | 2019 |
| MP Seafood Consulting Limited | Professional & scientific | 2022 |
| MR. E Mysteries Ltd | Manufacturing | 2019 |
| Mums Hub Health and Wellbeing CIC | Education | 2024 |
| My NKB Limited | Administrative & support | 2023 |
| Mybella Limited | Real estate | 2015 |
| MYX Properties (Holdings) Limited | Real estate | 2015 |
| MYX Properties Limited | Extraterritorial | 2015 |
| N W Transporter Parts Limited | Wholesale & retail | 2018 |
| NA SG Hayes Investments Limited | Real estate | 2024 |
| Naturespace Group Limited | Other services | 2023 |
| Nayco 3 Limited | Extraterritorial | 2013 |
| Nayco 6 Ltd | Extraterritorial | 2024 |
| Nbjem Developments Ltd | Administrative & support | 2022 |
| NDS Detailing Ltd | Wholesale & retail | 2019 |
| Necka Limited | Administrative & support | 2015 |
| Needham Consulting Ltd | Professional & scientific | 2018 |
| NEO Advisors Ltd | Professional & scientific | 2017 |
| NEO Collective Ltd | Professional & scientific | 2017 |
| Nero Otto Ltd | Professional & scientific | 2025 |
| New PUB Company Davenham Limited | Hospitality | 2016 |
| Newid Limited | Professional & scientific | 2020 |
| Next Generation Consultants Ltd | Professional & scientific | 2025 |
| NG Bathrooms Limited | Construction | 2019 |
| NG Bespoke Limited | Construction | 2026 |
| NG Group Holdings Limited | Financial services | 2026 |
| NG Trade Supplies Limited | Wholesale & retail | 2026 |
| Nick Blamphin Consulting Limited | Professional & scientific | 2024 |
| Nicola Cerven Ltd | Other services | 2025 |
| Nicole James Ltd | Other services | 2018 |
| Nigel Grindley Limited | Construction | 2004 |
| NJM Accounting Limited | Professional & scientific | 2015 |
| NJM Bookkeeping Limited | Professional & scientific | 2009 |
| Noctuis Limited | Professional & scientific | 2016 |
| Nonogon Ltd | Professional & scientific | 2026 |
| North ENG Ltd | Professional & scientific | 2020 |
| North Leigh Park (Leigh) Management Company Limited | Households | 2021 |
| North Real Estate Ltd | Real estate | 2017 |
| North Star Business Consultants Limited | Professional & scientific | 2024 |
| North West Beauty Limited | Education | 2021 |
| North West Shutters Limited | Wholesale & retail | 2007 |
| Northern Trading Aggregates Ltd | Administrative & support | 2026 |
| Northern Trading Holdco Limited | Financial services | 2022 |
| Northern Trading Plastics Ltd. | Administrative & support | 2019 |
| Northwich Victoria Club Company Limited | Real estate | 1877 |
| Norton and Rogers Ltd | Real estate | 2016 |
| Noswad Consulting Ltd | Information & communication | 2022 |
| Noswad LLP | | 2021 |
| Novare Limited | Real estate | 2023 |
| Novus Property Limited | Real estate | 2015 |
| NSZ Medical Services Ltd | Health & social care | 2022 |
| Nunsmere Hall Limited | Extraterritorial | 2013 |
| Nunsmere Limited | Hospitality | 2013 |
| Nursery Fields (North Bersted) Management Company Limited | Households | 2025 |
| Nutwood (Roby) Management Company Limited | Households | 2019 |