| Morris Architectural Design Ltd | Professional & scientific | 2020 |
| Mortrad Ltd | Wholesale & retail | 2021 |
| Mosaic Productions Ltd | Information & communication | 2019 |
| Moseley & Moore Limited | Other services | 2024 |
| Motion Recruitment Partners Limited | Administrative & support | 2005 |
| Motiv Gym Wear Ltd | Manufacturing | 2024 |
| Moto Junkies Limited | Arts & recreation | 2022 |
| Motorsmart Vehicles Limited | Wholesale & retail | 2021 |
| Motron Group Ltd | Wholesale & retail | 2019 |
| Moulders Consulting Limited | Professional & scientific | 2023 |
| Mount Pleasant Mews (Newton Abbot) Management Company Limited | Real estate | 2006 |
| MP Aesthetics Ltd | Health & social care | 2016 |
| MP Training & Recruitment Ltd | Administrative & support | 2026 |
| Mphes Ltd | Construction | 2016 |
| Mpower Electrical Services Limited | Construction | 2025 |
| MR Nicholas J Talbot Ltd | Health & social care | 2007 |
| MRC Electrical Limited | Construction | 2023 |
| Msgp Limited | Real estate | 2015 |
| MSS Lettings Limited | Households | 2020 |
| MT Consulting (UK) Limited | Other services | 2013 |
| MT Store Ltd | Administrative & support | 2018 |
| Muchbetter Limited | Professional & scientific | 2014 |
| Mudge Drylining Limited | Construction | 2003 |
| Muir Engineering (Europe) Limited | Wholesale & retail | 1999 |
| Mulberry Education Limited | Education | 2016 |
| Mulberry Gardens (Cornwall) Management Company Limited | Households | 2021 |
| Mulciber Limited | Administrative & support | 2010 |
| Murdoch Holdings Limited | Other services | 2018 |
| Murdoch Systems Ltd | Administrative & support | 2025 |
| Murray Denton Group Ltd | Financial services | 2023 |
| Murray Stays Limited | Real estate | 2023 |
| Murvi Motorcaravans Limited | Wholesale & retail | 1995 |
| Muse E2 Limited | Other services | 2021 |
| Must Have Property Limited | Real estate | 2017 |
| MX Vice Limited | Information & communication | 2011 |
| My Closet Dreams Ltd | Wholesale & retail | 2024 |
| My Vape Store Dawlish Ltd | Wholesale & retail | 2017 |
| My Vape Store Filton Ltd | Wholesale & retail | 2018 |
| My Vape Store Paignton Ltd | Wholesale & retail | 2022 |
| My Vape Store Southmead Ltd | Wholesale & retail | 2017 |
| My Vape Store Torquay Ltd | Wholesale & retail | 2019 |
| My Water Limited | Real estate | 2017 |
| My-Shrooms Limited | Agriculture & fishing | 2023 |
| Myacorn Limited | Information & communication | 2009 |
| Mycarebubble Ltd | Information & communication | 2024 |
| Myelixir Consultancy Ltd | Professional & scientific | 2021 |
| Myelixir Developments Ltd | Construction | 2021 |
| Myers (SW) Ltd | Professional & scientific | 2007 |
| Myerscough & Causley Limited | Real estate | 2017 |
| Myra Group Ltd | Real estate | 2026 |
| Mystic Wood LLP | | 2004 |
| N Smale Roofing Limited | Construction | 2013 |
| NA JQ Limited | Hospitality | 2018 |
| Na&D Ltd | Other services | 2019 |
| Nabf Locum Services Limited | Professional & scientific | 2015 |
| Nadeau Pasquier Ltd | Information & communication | 2022 |
| Nakashima Marine Propulsion Ltd | Manufacturing | 2024 |
| Nama Fitness and Wellness Ltd. | Arts & recreation | 2019 |
| Nananoodles Ltd | Hospitality | 2026 |
| Naomi Fisher Psychology Limited | Health & social care | 2021 |
| Napodos Limited | Administrative & support | 2011 |
| Narwhale Holdings Ltd | Administrative & support | 2019 |
| Nash Service Management Limited | Information & communication | 2016 |
| Nashdun Ltd | Extraterritorial | 2026 |
| National Hotel Services Ltd | Administrative & support | 2021 |
| National Hotels Limited | Hospitality | 2018 |
| Natural Body Sculpt Limited | Health & social care | 2019 |
| Navexis Limited | Professional & scientific | 2026 |
| Navguard Event Solutions Ltd | Administrative & support | 2025 |
| Navigation Financial Planning Limited | Financial services | 2018 |
| Ncwilliamson Ltd | Construction | 2021 |
| NDL Healthcare Ltd | Health & social care | 2025 |
| Neapolitan Ltd | Information & communication | 1999 |
| Neat Experts Limited | Construction | 1999 |
| Nebrak Limited | Manufacturing | 1992 |
| Nectra Consulting Ltd | Information & communication | 2024 |
| Neff Properties UK Ltd | Real estate | 2020 |
| Negatex (Developments) Limited | Construction | 2012 |
| Negatex Limited | Construction | 1976 |
| Nelion Limited | Professional & scientific | 2026 |
| Nellcore Limited | Construction | 2025 |
| Nero Translations Limited | Professional & scientific | 2006 |
| Nestico Ltd | Real estate | 2025 |
| Nestinn Properties Ltd | Real estate | 2025 |
| Netley Developments Ltd | Construction | 2025 |
| Networking Business Referrals (SW) Ltd | Other services | 2019 |
| Neuronest South West CIC | Education | 2025 |
| Neurora Ltd | Education | 2023 |
| Neutral Technologies Ltd | Information & communication | 2026 |
| New Creations | Manufacturing | 1995 |
| New Horizon Homes Limited | Extraterritorial | 2011 |
| New Landscaping Solutions Ltd | Administrative & support | 2021 |
| Newable AHK Limited | Financial services | 2025 |
| Newbay Electrical Services Ltd | Construction | 2008 |
| Newbay Lettings Ltd | Real estate | 2026 |
| Newberry Electrical Services Limited | Construction | 2017 |
| Newglaze Systems Ltd | Manufacturing | 2023 |
| Newhouse Property Company Limited | Construction | 2011 |
| Newincco 1218 Ltd | Information & communication | 2012 |
| Newinnton Developments Ltd | Construction | 2025 |