| Lyndsays Deli Limited | Hospitality | 2019 |
| Lynn Johnson Consultants Limited | Administrative & support | 2019 |
| Lynnwood Wholesale Ltd | Wholesale & retail | 2018 |
| Lynwood Eden Villas Ltd | Health & social care | 2025 |
| Lynwood Foods NE Ltd | Hospitality | 2025 |
| Lynwood Fulwell Ltd | Health & social care | 2025 |
| Lynwood Healthcare Ltd | Health & social care | 2017 |
| Lynwood Property Ltd | Real estate | 2017 |
| Lynwood Prudhoe Ltd | Health & social care | 2025 |
| Lynx RA1 Limited | Real estate | 2021 |
| Lyons Art Limited | Professional & scientific | 2019 |
| Lyransse Ltd | Manufacturing | 2023 |
| Lyre Solutions Ltd | Professional & scientific | 2026 |
| Lyric Wines Throckley Ltd | Wholesale & retail | 2025 |
| Lyskamm Limited | Professional & scientific | 2023 |
| M & a Bell (Electricals) Limited | Other services | 2012 |
| M & a Laundry Services Limited | Other services | 2015 |
| M & a Mini Market Ltd | Wholesale & retail | 2021 |
| M & C Residential Ltd. | Real estate | 2015 |
| M & C Roofing Contractors Limited | Construction | 2003 |
| M & F Estates Ltd | Real estate | 2026 |
| M & G Windows Limited | Manufacturing | 2003 |
| M & J Resurfacing Ltd | Construction | 2017 |
| M & K Estates Ltd | Real estate | 2024 |
| M & L Utilities Ltd | Construction | 2020 |
| M & P Mason Ltd | Transport & logistics | 2016 |
| M & R Foods Ltd | Hospitality | 2017 |
| M & S Construction Project Management Limited | Construction | 2015 |
| M & S Motorcycles Holdings Limited | Wholesale & retail | 1989 |
| M & W (NE) Ltd | Hospitality | 2025 |
| M . Flora Fashions Ltd | Wholesale & retail | 2019 |
| M a Building Services Ltd | Construction | 2023 |
| M a S Autoparts Limited | Wholesale & retail | 2017 |
| M a S Lifting Services Ltd | Construction | 2016 |
| M a S Properties (NE) Limited | Real estate | 2021 |
| M and F Contracts Ltd | Administrative & support | 2025 |
| M and M North East Ltd | Wholesale & retail | 2015 |
| M Blakey Construction Ltd | Construction | 2014 |
| M Bray Property and Investments Limited | Real estate | 2025 |
| M Bryan Groundworks Limited | Construction | 2012 |
| M C Associates (Europe) Ltd | Professional & scientific | 2014 |
| M C C Developments Newcastle Limited | Construction | 2004 |
| M C C Properties Newcastle Limited | Construction | 2004 |
| M C Inspection Services Limited | Professional & scientific | 2016 |
| M Cladding Ltd | Construction | 2022 |
| M Clay Services Ltd | Transport & logistics | 2024 |
| M D Holdings (2025) Limited | Financial services | 2025 |
| M D Plant Ltd | Manufacturing | 2012 |
| M Davies Construction Limited | Construction | 2024 |
| M E C (North East) Ltd | Construction | 2015 |
| M F Wakelin Property Ltd | Real estate | 2025 |
| M Forster Design Ltd | Professional & scientific | 2020 |
| M Grocery Ltd | Wholesale & retail | 2025 |
| M H Windtech Ltd | Professional & scientific | 2018 |
| M J G Publishing Limited | Information & communication | 2015 |
| M J S Project Management Limited | Professional & scientific | 1997 |
| M J Uddin Ltd | Professional & scientific | 2024 |
| M K Commercial Properties Ltd | Hospitality | 2017 |
| M L Fantin Ltd | Wholesale & retail | 2014 |
| M Laverick Limited | Professional & scientific | 2016 |
| M Lewis Limited | Real estate | 2020 |
| M M Civils Ltd | Construction | 2020 |
| M M Devlin Ltd | Transport & logistics | 2008 |
| M M J D Properties Ltd | Real estate | 2024 |
| M Market Ltd | Wholesale & retail | 2025 |
| M Realisations 2025 Limited | Construction | 1998 |
| M S R Traders NCL Ltd | Hospitality | 2026 |
| M Saleem Properties Ltd | Real estate | 2025 |
| M T S Property Rentals Limited | Real estate | 2026 |
| M Tanvir Properties Limited | Real estate | 2018 |
| M Ullah Ltd | Education | 2022 |
| M W Arthur Ltd | Information & communication | 2020 |
| M W Fibre Splice Limited | Information & communication | 2016 |
| M Walton Fitness Limited | Health & social care | 2025 |
| M Z L (NE) Ltd | Hospitality | 2019 |
| M&C Construction NE Ltd | Construction | 2024 |
| M&C Developments NE Ltd. | Construction | 2016 |
| M&C Enterprises Limited | Hospitality | 2021 |
| M&C Group Services Ltd | Financial services | 2022 |
| M&E Beauty Ltd | Other services | 2026 |
| M&H Legal Ltd | Professional & scientific | 2013 |
| M&K Accounting Ltd | Professional & scientific | 2022 |
| M&K Brickworks (NE) Ltd | Construction | 2021 |
| M&Kj Limited | Financial services | 2022 |
| M&L Electrical Contractors Limited | Construction | 2014 |
| M&M Health Care Ltd | Health & social care | 2016 |
| M&M Property Solutions Northeast Ltd | Real estate | 2024 |
| M&M Saloon Ltd | Wholesale & retail | 2025 |
| M&M Saloon Ltd Ltd | Other services | 2025 |
| M&N Burrow Ltd | Professional & scientific | 2026 |
| M&R Ceilings and Partitions Limited | Construction | 2024 |
| M&R Commercial Limited | Real estate | 2018 |
| M&Sha Retail Ltd | Wholesale & retail | 2026 |
| M&Y Properties Northeast Ltd | Real estate | 2024 |
| M-P Invest Ltd | Real estate | 2025 |
| M. & S. Motorcycles Limited | Wholesale & retail | 1957 |
| M. H. Jones Chirurgia Limited | Health & social care | 2018 |
| M. M. Younes Properties Ltd | Real estate | 2008 |
| M. Robson's Specialised Services Ltd | Professional & scientific | 2014 |
| M.A Hair Design Ltd | Other services | 2018 |