| MAG Electrical Limited | Construction | 2021 |
| Magpie Wood Caravans and Glamping Limited | Hospitality | 2019 |
| Mahmut Bozkurt Ltd | Hospitality | 2017 |
| Manhatten FM Limited | Administrative & support | 2022 |
| Manhatten Furnishings Limited | Wholesale & retail | 2020 |
| Manhatten Property Solutions Limited | Real estate | 2015 |
| Manor Investments (Guisborough) Ltd | Financial services | 2018 |
| Marama Ltd | Real estate | 2023 |
| Margrove Property Group Ltd | Real estate | 2025 |
| Mark Harris Services Ltd | Information & communication | 2018 |
| Markphilliprobertson Ltd | Transport & logistics | 2026 |
| Marsh Construction Group Limited | Professional & scientific | 2026 |
| Marske United Football Club Limited | Arts & recreation | 2023 |
| Massmoor Limited | Professional & scientific | 2020 |
| MAW Project Consultancy Ltd | Information & communication | 2013 |
| Maxima Solutions Limited | Information & communication | 2011 |
| MC EHS Consultants Ltd | Professional & scientific | 2024 |
| MC Engineering Services Ltd | Information & communication | 2023 |
| Mccristall Construction Services Ltd | Construction | 2024 |
| MCJ Grey Ltd | Real estate | 2025 |
| Mega Mike Ltd | Wholesale & retail | 2026 |
| Mell Mason Furniture Design Ltd | Professional & scientific | 2013 |
| MHW Yorkshire Ltd | Wholesale & retail | 2025 |
| Micklow Brewing Company Ltd | Manufacturing | 2023 |
| Micklow Taps Ltd | Hospitality | 2025 |
| Middle Farm Management (Ellerby) Limited | Real estate | 2011 |
| Milton Pillars Ltd | Hospitality | 2025 |
| MIN DU (Saltburn) Ltd | Hospitality | 2023 |
| Mirow Properties Limited | Real estate | 2024 |
| MJC Safeguarding Consultancy Limited | Professional & scientific | 2017 |
| MJH Holdings (North East) Ltd | Financial services | 2025 |
| MKH Properties (North East) Limited | Real estate | 2018 |
| ML Thrower Logistics Ltd | Transport & logistics | 2025 |
| MO Fast Food Ltd | Hospitality | 2025 |
| Mobile Mech Solution Ltd | Wholesale & retail | 2026 |
| Mossa Pilates Limited | Arts & recreation | 2024 |
| MR and MRS M Shaw Limited | Wholesale & retail | 2015 |
| MSC Wind & Maritime Ltd | Construction | 2026 |
| MTW Profitable Business Solutions Limited | Professional & scientific | 2024 |
| Muddy-Paws Daycare Ltd | Other services | 2021 |
| Mylah Skye Ltd | Manufacturing | 2025 |
| N.E. Renewable Solutions Limited | Professional & scientific | 2017 |
| Nanny Bears Day Care Centre Limited | Health & social care | 2013 |
| Naomi Winters Priesthood Ministry C.I.C. | Other services | 2026 |
| Nextgen Civils Ltd Ltd | Manufacturing | 2025 |
| Nicofix (Europe) Limited | Hospitality | 2007 |
| Nixspeed Ltd | Wholesale & retail | 2026 |
| NJS Automation Ltd | Energy | 2022 |
| Noor Tandoori Limited | Hospitality | 2023 |
| Nordic Yorkshire Ltd | Professional & scientific | 2024 |
| North East Engineering Solutions Ltd | Professional & scientific | 2021 |
| Northallerton and District Motor Cycle Club Limited | Arts & recreation | 1979 |
| Northern Fleet Services Ltd | Wholesale & retail | 2025 |
| Northern Generator Services Ltd | Manufacturing | 2024 |
| NR Inspection Ltd | Professional & scientific | 2013 |
| Nurturing Connections and Well-Being CIC | Health & social care | 2024 |
| NW Plant Limited | Transport & logistics | 2023 |
| Office Hours Limited | Professional & scientific | 2022 |
| OH SO Aesthetics Limited | Health & social care | 2019 |
| Olive OR Twist Cocktail Bar Limited | Hospitality | 2022 |
| One Kitchens & Bedrooms Ltd | Construction | 2025 |
| Optima Circuit Ltd | Manufacturing | 2025 |
| Orwell Maintenance Limited | Administrative & support | 2010 |
| Osbourne House Farm Cottages Limited | Hospitality | 2013 |
| P a Collins (Farrier) Limited | Professional & scientific | 2004 |
| P&L Tech Ltd | Information & communication | 2022 |
| P. Prudom & SON Limited | Agriculture & fishing | 2006 |
| Packetworks Ltd | Information & communication | 2008 |
| Paladin Atlantis Ltd | Transport & logistics | 2019 |
| Parsell Engineering Limited | Construction | 2013 |
| Paul Collins Racing Limited | Arts & recreation | 2017 |
| PC Inspection Limited | Professional & scientific | 2011 |
| PCX Solutions Ltd | Professional & scientific | 2026 |
| Peak Cottage Management Ltd | Households | 2021 |
| Peak Staycations Ltd | Hospitality | 2022 |
| Pearl Street Properties Limited | Real estate | 2018 |
| Pebble.Gg Limited | Information & communication | 2024 |
| Pepper Dogs Ltd | Wholesale & retail | 2019 |
| PER Aspera Ltd | Manufacturing | 2019 |
| Peter F. Short (Butchers) Limited | Real estate | 1975 |
| Petflapdoors.Co.Uk Ltd | Construction | 2024 |
| Pipeline Precision Engineering Ltd | Manufacturing | 2009 |
| Piper and Muse Photography Ltd | Professional & scientific | 2024 |
| Pizza House Abingdon Ltd | Hospitality | 2016 |
| Pizza House Xpress Ltd | Hospitality | 2025 |
| Pizza Shop Abingdon Ltd | Hospitality | 2024 |
| Planet Oomph! Ltd | Wholesale & retail | 2025 |
| Platform 360 Ltd | Other services | 2021 |
| Playmaker Promotions Ltd | Arts & recreation | 2017 |
| Plymstock Safety Services Limited | Public administration | 2014 |
| Polynesia Associates Ltd | Financial services | 2016 |
| Porter Brown Enterprises Ltd | Wholesale & retail | 2026 |
| PR Groundworks NE Ltd | Construction | 2024 |
| Precomm Ltd | Professional & scientific | 2025 |
| Premier E-Commerce Solutions Ltd | Wholesale & retail | 2025 |
| Prescribed Aesthetics Limited | Health & social care | 2023 |
| Prestige UK Trade Ltd | Manufacturing | 2024 |
| Project Control NE Limited | Professional & scientific | 2016 |
| Project Site Services Ltd | Construction | 2022 |
| Properties by J&A Ltd | Real estate | 2025 |