| Mini Crane Hire Midlands Limited | Construction | 2008 |
| Mint Construction International Ltd | Construction | 2024 |
| Mint Logistics Ltd | Transport & logistics | 2016 |
| Mint Projects International Limited | Construction | 2017 |
| Miral Links Ltd | Wholesale & retail | 2025 |
| Mister Discount Limited | Wholesale & retail | 1999 |
| Mithalr Limited | Health & social care | 2014 |
| Mixedbywillo Ltd | Information & communication | 2024 |
| MJ Racing Ltd | Arts & recreation | 2025 |
| MLR Cladding Services Limited | Construction | 2013 |
| MLS & Sons Limited | Manufacturing | 2024 |
| Mobile Cranes UK Limited | Administrative & support | 2025 |
| Mobile Mechanical Support Limited | Wholesale & retail | 2017 |
| Mobile Repair Ltd | Other services | 2026 |
| Mobileflexi Cleaners Limited | Administrative & support | 2025 |
| Mobilize Hire Limited | Administrative & support | 2013 |
| Mobra Ltd | Wholesale & retail | 2024 |
| Mohan Trans Ltd | Transport & logistics | 2024 |
| Momenabadi Lettings Ltd | Real estate | 2026 |
| Moneycom UK Limited | Real estate | 1997 |
| Monmore Confectionery (Midlands) Limited | Wholesale & retail | 2002 |
| Monstera Media Ltd | Professional & scientific | 2023 |
| Montagu Mentoring Ltd | Professional & scientific | 2025 |
| Moon Homes Ltd | Real estate | 2017 |
| Moon Mobile Repairs Ltd | Wholesale & retail | 2025 |
| Moore-Elec Ltd | Construction | 2019 |
| Moot Bakes Limited | Hospitality | 2025 |
| More Than Talking Monika Klarecka Ltd | Administrative & support | 2014 |
| Moreplus Care Ltd | Administrative & support | 2019 |
| MORNING7STAR Ltd | Administrative & support | 2022 |
| Morris Car and Commercials Ltd | Wholesale & retail | 2017 |
| Morstone Limited | Wholesale & retail | 2020 |
| Morton Auto Tech Ltd | Wholesale & retail | 2017 |
| MOTION360 Limited | Transport & logistics | 2024 |
| MOTOX1911 Ltd | Wholesale & retail | 2015 |
| Mountford Associates Limited | Administrative & support | 2016 |
| Moyoz Limited | Health & social care | 2023 |
| MPG Interiors Ltd | Construction | 2017 |
| MPS Property & Associates (UK) Ltd | Construction | 2020 |
| MR Mann Retail Ltd | Wholesale & retail | 2023 |
| Mr.Lock 247 Limited | Wholesale & retail | 2020 |
| MS and MT Limited | Wholesale & retail | 2025 |
| MS Construction & Groundworks Ltd | Construction | 2026 |
| MS Midland Construction Ltd | Construction | 2014 |
| MS Soul Food Ltd | Hospitality | 2026 |
| MSA UK Services Ltd | Wholesale & retail | 2025 |
| MSR Property Services Limited | Real estate | 2025 |
| Mtec Midlands Ltd | Wholesale & retail | 2021 |
| Mthwakazi Queens CIC | Education | 2018 |
| MTS Medical Transport Services Ltd | Transport & logistics | 2024 |
| MTU Construction Ltd | Construction | 2025 |
| Mueller Europe Investment Company Ltd | Manufacturing | 2015 |
| Mugadi Healthcare Services Ltd | Health & social care | 2022 |
| Multi Skill Ltd | Construction | 2026 |
| Multishine Ltd | Wholesale & retail | 2023 |
| Mundh Services Ltd | Transport & logistics | 2025 |
| Mundh Transport Ltd | Transport & logistics | 2024 |
| Munich Ltd | Manufacturing | 2025 |
| Murray 2 Limited | Financial services | 2021 |
| Music Lovers CIC | Arts & recreation | 2024 |
| Muza Enterprises Limited | Health & social care | 2019 |
| My Artsy Party Limited | Arts & recreation | 2023 |
| My Wellness Engineering Ltd | Water & waste | 2019 |
| N Kang Estates Ltd | Real estate | 2021 |
| N&B&B&N Ltd | Other services | 2026 |
| Nadar Logistics Ltd | Transport & logistics | 2025 |
| Nagah Capital Ltd | Financial services | 2026 |
| Naila Ghalib Limited | Professional & scientific | 2018 |
| Nanak Homes Derby Ltd | Real estate | 2025 |
| Nanez Care Ltd | Health & social care | 2019 |
| Nanny Creole Limited | Health & social care | 2023 |
| Nanu Transport Ltd | Transport & logistics | 2024 |
| Narkul Holdings Ltd | Real estate | 2026 |
| Narrative Change Consulting Ltd | Professional & scientific | 2024 |
| Nathi Group Limited | Public administration | 2026 |
| Nauriceselfcare Ltd | Professional & scientific | 2024 |
| Nautilus Designs Limited | Manufacturing | 2017 |
| NAV Haulage & Construction Limited | Construction | 2022 |
| NCH (UK) Limited | Manufacturing | 1964 |
| ND & Sons Properties Ltd | Real estate | 2026 |
| Ndamba Sport Management Ltd | Arts & recreation | 2024 |
| Neale Stone Property Group Ltd | Real estate | 2026 |
| Neat Plastics Ltd | Wholesale & retail | 2023 |
| Nehhealthcare Ltd | Health & social care | 2025 |
| Nellus's Ltd | Wholesale & retail | 2023 |
| Neria Foods Limited | Transport & logistics | 2025 |
| Netmatrix Consultancy Services Limited | Information & communication | 2011 |
| New Century Systems Limited | Manufacturing | 1985 |
| New Diamond Transport Ltd | Transport & logistics | 2019 |
| New Fit Kitchen & Bedrooms Ltd | Construction | 2017 |
| New Heaven Retail Limited | Wholesale & retail | 2017 |
| New Lights Properties Ltd | Real estate | 2024 |
| New Mayo Group Ltd | Health & social care | 2025 |
| New Panjabi Junction Ltd | Hospitality | 2025 |
| New Road Commercial Limited | Real estate | 1953 |
| New to Nuclear Ltd | Professional & scientific | 2024 |
| New Triumph Limited | Administrative & support | 2013 |
| Newey Holdings Limited | Professional & scientific | 2017 |
| Newton Electrical Limited | Construction | 2020 |
| Nexgen Foods Ltd | Hospitality | 2020 |