| Minah Luxe Group Ltd | Wholesale & retail | 2025 |
| Mind Body & Spirit Ltd | Wholesale & retail | 2015 |
| Mindful Art Club CIC | Health & social care | 2022 |
| Mindset Sport and Performance Psychology Ltd | Education | 2025 |
| Mindsmiththinking Limited | Health & social care | 2021 |
| Mindwarp Software Ltd | Information & communication | 2024 |
| Mineralogica Ltd | Professional & scientific | 2025 |
| Minerva Cafe Ltd | Hospitality | 2020 |
| Minerva Composites Ltd | Manufacturing | 2024 |
| Minerva Technical Ltd | Manufacturing | 2021 |
| Mini Cooper Register Ltd | Arts & recreation | 2024 |
| Mini Delikatesy Ltd | Wholesale & retail | 2014 |
| Ministry of Coffee Ltd | Wholesale & retail | 2010 |
| Miragecharters UK Limited | Transport & logistics | 2014 |
| Miramar Holdings (SW) Ltd | Financial services | 2022 |
| Miramar Properties (SW) Ltd | Real estate | 2025 |
| Miramar Property Development 2026 Ltd | Construction | 2026 |
| Mirreco IP Ltd | Administrative & support | 2025 |
| Mirreco UK Ltd | Professional & scientific | 2019 |
| Mirrordrop Limited | Professional & scientific | 2014 |
| Misalsacubana Limited | Extraterritorial | 2020 |
| Miss Chelsea Pope Limited | Arts & recreation | 2020 |
| Miss KAL Limited | Information & communication | 2014 |
| Miss Pinks (Ridgeway) Limited | Wholesale & retail | 2026 |
| Miss Pinks Florist Limited | Wholesale & retail | 2022 |
| Mission Escape (Exeter) Limited | Arts & recreation | 2018 |
| Mission Escape (Plymouth) Limited | Arts & recreation | 2018 |
| Mission Inc Holdings Limited | Information & communication | 2024 |
| Mission Inc Ltd | Professional & scientific | 2003 |
| Mista Blue Ltd | Wholesale & retail | 2018 |
| Mitchell Architects Limited | Professional & scientific | 2006 |
| Mitchell Roofing (SW) Ltd | Construction | 2022 |
| MITCHELLDT9 Ltd | Professional & scientific | 2019 |
| Mitchpin Limited | Real estate | 1966 |
| Mitrad Limited | Professional & scientific | 2019 |
| Mixatone Ltd | Other services | 2022 |
| MJ Building Developments Ltd | Construction | 2025 |
| MJ Financial (SW) Limited | Financial services | 2023 |
| MJA Wholesale Ltd | Wholesale & retail | 2025 |
| Mjbmotorsports Ltd | Wholesale & retail | 2025 |
| MJC Passive Fire Ltd | Construction | 2025 |
| MJD Family Limited | Other services | 2024 |
| MJG Brickwork Limited | Construction | 2017 |
| MJH (London) Limited | Professional & scientific | 2014 |
| MJK Breeze Properties Limited | Construction | 2015 |
| Mjml South West Limited | Real estate | 2015 |
| MJP Plymouth Limited | Real estate | 2015 |
| MJR Specialist Logistics Ltd | Transport & logistics | 2024 |
| MJT Surveyors Limited | Professional & scientific | 2017 |
| MJV Consultancy SW Limited | Professional & scientific | 2024 |
| MK 2010 CS Ltd | Wholesale & retail | 2010 |
| MK 2017 Ltd | Hospitality | 2017 |
| MK Aviation Consultancy Ltd | Professional & scientific | 2020 |
| MK Heat Ltd | Construction | 2022 |
| MK Heat Property Services Ltd | Construction | 2026 |
| MK Wash N Go Ltd | Administrative & support | 2025 |
| MK3 Developments Ltd | Construction | 2025 |
| MKE Reed Telecomms Ltd | Manufacturing | 2016 |
| MKF Property Limited | Real estate | 2019 |
| Mkmk Services Ltd | Administrative & support | 2019 |
| MKX Technical Ltd | Administrative & support | 2016 |
| ML (South West) Ltd | Wholesale & retail | 2024 |
| ML GRP Services Ltd | Manufacturing | 2021 |
| MLA College Ltd | Education | 2014 |
| MLD Promotions Ltd | Other services | 2023 |
| MLE Carpentry and Building Ltd | Construction | 2025 |
| MLL Holdings Ltd | Hospitality | 2019 |
| MLS Homes (SW) Ltd | Real estate | 2023 |
| MLT Enterprises Ltd | Administrative & support | 2019 |
| MLT International Ltd | Administrative & support | 2015 |
| MM Construction (SW) Ltd | Construction | 2022 |
| MM FLAT4YOU Ltd | Real estate | 2025 |
| MM21 Properties Limited | Households | 2022 |
| MME Services Limited | Construction | 2000 |
| Mmhos Ltd | Health & social care | 2019 |
| MMJ Stores Limited | Wholesale & retail | 2026 |
| Mmjv Consult Ltd | Education | 2026 |
| MMK Automotive Limited | Wholesale & retail | 2021 |
| MMM Retail Limited | Wholesale & retail | 2020 |
| MMV Apartment Management Company NO.1 Limited | Households | 1988 |
| Mmw&Jgr Properties LLP | | 2010 |
| MN Seafood Partners Ltd | Wholesale & retail | 2023 |
| MNJ Properties Ltd | Real estate | 2022 |
| Mnkpub Ltd | Hospitality | 2023 |
| MNS Solutions Limited | Extraterritorial | 2007 |
| MO Properties Plymouth Ltd | Real estate | 2025 |
| Mo'Bay Clothing Ltd | Wholesale & retail | 2014 |
| Mobile Ablation Solutions Limited | Professional & scientific | 2015 |
| Mobile Carpets & Flooring SW Ltd | Construction | 2012 |
| Mobile Mechanics Plymouth Limited | Wholesale & retail | 2018 |
| Mobile Washing Ltd | Wholesale & retail | 2024 |
| Mobilemechanicsw Ltd | Wholesale & retail | 2025 |
| Mobility Equipment Training Centre Ltd | Manufacturing | 2018 |
| Mocha and Munchies Limited | Manufacturing | 2025 |
| Mochi Kitchen Ltd | Hospitality | 2024 |
| Mock (Plymouth) Limited | Transport & logistics | 1964 |
| MOD Box Spaces Limited | Hospitality | 2014 |
| Modbox Developments Limited | Construction | 2023 |
| Modbox Spaces (the Point) Limited | Construction | 2018 |
| Modbury Estates Ltd | Real estate | 2021 |