| Langver Engineering Limited | Manufacturing | 2004 |
| Langver Limited | Real estate | 1994 |
| Laser Trader Limited | Wholesale & retail | 2000 |
| Lawson 2 LET Limited | Real estate | 2020 |
| LC North Ltd | Arts & recreation | 2025 |
| Leafshaw Limited | Agriculture & fishing | 1997 |
| Leeds 27 Limited | Construction | 2006 |
| Leeds Fabric Company Limited | Wholesale & retail | 2022 |
| Legal Estate Administration Ltd | Administrative & support | 2025 |
| Leia Consulting Ltd | Administrative & support | 2026 |
| Leyburn PUB Ltd | Hospitality | 2020 |
| LG Golf Ltd | Wholesale & retail | 2025 |
| Lightwater Business Development Ltd | Professional & scientific | 2013 |
| Limitless Event Production Limited | Administrative & support | 2025 |
| Linden Construction Ltd | Construction | 2005 |
| Linden Tree Apartments Thirsk Ltd | Hospitality | 2026 |
| Little Green Mews Management Company Ltd | Households | 2014 |
| Little Learners Village Ltd | Arts & recreation | 2024 |
| Little Lions DEN Limited | Manufacturing | 2023 |
| Little Nags Ltd | Agriculture & fishing | 2021 |
| London Barber 5 Ltd | Other services | 2024 |
| Longfield Lifestyles (GB) Limited | Wholesale & retail | 2021 |
| Lots of Bits Ltd | Information & communication | 2022 |
| Louis Chew Ltd | Real estate | 2026 |
| LOW Property Investments Ltd | Real estate | 2024 |
| Lowe Hospitality Group Ltd | Hospitality | 2025 |
| Lsect Ltd | Education | 2022 |
| Lucstar Construction Ltd | Construction | 2026 |
| Luke Miller & Associates Limited | Extraterritorial | 2015 |
| Luke Williams Racing Limited | Arts & recreation | 2018 |
| Lumberzak Ltd | Construction | 2025 |
| Lumous Consultancy Limited | Professional & scientific | 2025 |
| LVV Property Ltd | Real estate | 2022 |
| Lydan Ltd. | Hospitality | 2017 |
| Lydan Properties Ltd | Real estate | 2026 |
| Lynden Consultancy Limited | Professional & scientific | 2010 |
| Lynden Limited | Professional & scientific | 2026 |
| M Balderston Poultry Sexing Limited | Other services | 2022 |
| M&C Capital Limited | Financial services | 2022 |
| M&C Property (North) Limited | Real estate | 2025 |
| M&N Boersma Limited | Hospitality | 2013 |
| M.F. Refrigeration Limited | Administrative & support | 1987 |
| MAB Environment & Ecology Limited | Professional & scientific | 2008 |
| MAC (Yorkshire) Ltd | Transport & logistics | 2017 |
| Mace Management Consultancy Limited | Professional & scientific | 2021 |
| Magnus Innovations Limited | Wholesale & retail | 2025 |
| Mahgerre Ltd | Professional & scientific | 2024 |
| Mahoksa Ltd | Financial services | 2018 |
| Mains Site (Dalton) Limited | Real estate | 2026 |
| MAL Aviation Services Ltd | Education | 2025 |
| Maltings (Thirsk) Management Co. Limited(The) | Households | 1984 |
| Manedge Limited | Professional & scientific | 2012 |
| Manok Limited | Agriculture & fishing | 2022 |
| Manor Barns (Rainton) Management Limited | Households | 2022 |
| Mark Atkin Services Limited | Other services | 2015 |
| Mark Harris Ltd | Other services | 2016 |
| Martial Fit LLP | | 2004 |
| Maxwell Evans Estate Agents Limited | Real estate | 2012 |
| Maxwell Renewables Limited | Energy | 2016 |
| Mays Trading Limited | Wholesale & retail | 2017 |
| MB Aviation Ltd | Real estate | 2026 |
| MBA Engineering Systems Limited | Manufacturing | 2010 |
| Mcfo (Yorkshire) Limited | Agriculture & fishing | 2015 |
| Mcgm Limited | Households | 2021 |
| Mckee Upvc Window & Door Repair Limited | Construction | 2024 |
| MCS Business Consultancy Limited | Professional & scientific | 2012 |
| Meadow View (Carlton Miniott) Management Company Limited | Households | 2022 |
| Mercury Engineering Services Ltd | Professional & scientific | 2024 |
| Meridian Insurance Advisors Limited | Financial services | 2002 |
| Metropolitan Vickers Limited | Manufacturing | 2020 |
| MFL Worth Limited | Manufacturing | 2022 |
| MGC Enterprises Ltd | Real estate | 2025 |
| Milano Pizzeria Millgate Ltd | Hospitality | 2019 |
| Mill House Gardening Limited | Construction | 2016 |
| Mint Green Publishing Ltd | Information & communication | 2022 |
| Mismatched Limited | Wholesale & retail | 2025 |
| Mitech Northern Ltd | Construction | 2021 |
| MM Business (UK) Limited | Information & communication | 2012 |
| Mobile Barbering Academy Ltd | Education | 2017 |
| Monks & Cook Ltd | Professional & scientific | 2021 |
| Moon ALE Houses Limited | Hospitality | 2019 |
| Moon ALE Houses Properties Limited | Real estate | 2023 |
| Moonbadger Intelligence Limited | Information & communication | 2026 |
| Moorfields Development Limited | Construction | 2021 |
| Moose&Me Ltd | Wholesale & retail | 2023 |
| Mortime's Munchies Limited | Hospitality | 2024 |
| Mosleys Limited | Administrative & support | 2007 |
| Mossley Caravan & Trailer Storage Ltd. | Transport & logistics | 1996 |
| Motherdale Limited | Health & social care | 1986 |
| Mount ST John Equestrian LLP | | 2013 |
| Mount ST John Properties Limited | Real estate | 2018 |
| Mount ST John Sporting LLP | | 2011 |
| Mowbray Associates Limited | Professional & scientific | 2009 |
| Mowbray Electrical & Security Ltd | Construction | 2025 |
| Mowbray Hall Limited | Households | 2026 |
| Mpd:Architect Ltd | Professional & scientific | 2023 |
| MPI Access Ltd | Construction | 2026 |
| Mucky Pups Doggy Daycare Ltd | Other services | 2025 |
| Multichoice Vehicle Sales Limited | Wholesale & retail | 2005 |
| My Electrical Contractors Limited | Construction | 2013 |