| Monarch Laundry (York) Limited | Other services | 2002 |
| Money Street Limited | Professional & scientific | 2026 |
| Monk Fryston Bypass Limited | Extraterritorial | 2020 |
| Montwhelan Limited | Real estate | 1978 |
| Monty's Pubs Limited | Hospitality | 2025 |
| Moon Rest Limited | Manufacturing | 2025 |
| Moonfive Ltd | Information & communication | 2018 |
| Moorhay Limited | Transport & logistics | 2023 |
| Mooring Coffee Co Ltd | Wholesale & retail | 2026 |
| More Tatoes Limited | Education | 2012 |
| More Than Pilates Limited | Arts & recreation | 2008 |
| Mornington 2000 LLP | | 2008 |
| Mornington Holdings Ltd | Financial services | 2021 |
| Morton Yorks Ltd | Construction | 2024 |
| Mosley Gibson Limited | Households | 2020 |
| Moss Tyres and Autocare Ltd | Wholesale & retail | 2025 |
| Mossland Solutions Limited | Financial services | 2021 |
| Mossmentum Limited | Professional & scientific | 2025 |
| Moulds & Co Limited | Professional & scientific | 2002 |
| Mountford Consultancy Limited | Administrative & support | 2018 |
| Mouth Cancer Foundation Limited | Health & social care | 2004 |
| MR Yiks Ltd | Hospitality | 2022 |
| Mrcr Holdings Ltd | Wholesale & retail | 2024 |
| MRG Socials Limited | Information & communication | 2022 |
| MSA Property Developments Limited | Real estate | 2003 |
| Mses Group Ltd | Professional & scientific | 2023 |
| MSG Interim Management Ltd | Professional & scientific | 2012 |
| MTA Learning Limited | Professional & scientific | 2003 |
| Mtms Leisure Limited | Hospitality | 2024 |
| Muckles (UK) LLP | | 2011 |
| Multifuture Concepts Ltd | Administrative & support | 2018 |
| Munroe DNA Limited | Real estate | 2026 |
| Munroe K Developments Limited | Construction | 2019 |
| Munroe K Limited | Real estate | 1994 |
| Murgatroyd of Harrogate Ltd | Transport & logistics | 2019 |
| Murphy (Yorkshire) Ltd | Other services | 2015 |
| Mwsec Limited | Professional & scientific | 2013 |
| Mwsec Properties Ltd | Real estate | 2019 |
| My Purser Ltd | Transport & logistics | 2024 |
| My Route LLP | | 2008 |
| My Smart Link Limited | Information & communication | 2022 |
| My Smart Quote Limited | Information & communication | 2022 |
| N Dean Tree & Garden Services Ltd | Other services | 2019 |
| N T R Ltd | Manufacturing | 1979 |
| N-Ergy Limited | Professional & scientific | 2014 |
| N.J.Geddes Limited | Wholesale & retail | 2015 |
| N47 CS Ltd | Financial services | 2022 |
| N47 JP Ltd | Financial services | 2018 |
| N47 Park Hill Ltd | Real estate | 2023 |
| NAP House Holidays Ltd | Real estate | 2026 |
| Nash Software Applications Ltd | Information & communication | 2022 |
| Nathris Limited | Real estate | 2007 |
| Nationwide Trailer Parts Ltd | Wholesale & retail | 2009 |
| Naturaw Limited | Manufacturing | 2018 |
| Naturaw Pet Food Ltd | Manufacturing | 2017 |
| Navigator Pubs Limited | Hospitality | 2020 |
| Naylor Distribution Services Limited | Hospitality | 2018 |
| NB Consulting (Yorkshire) Ltd | Professional & scientific | 2023 |
| NB Hair Limited | Other services | 2016 |
| NDL Software Limited | Information & communication | 1981 |
| Nebula Eyecare Ltd | Health & social care | 2019 |
| Neil Holroyd Studio Ltd | Professional & scientific | 2017 |
| Neil Morrissey Photography Ltd | Information & communication | 2008 |
| NEO Social Limited | Professional & scientific | 2022 |
| Nesso Consult Ltd | Information & communication | 2025 |
| Nest Building Contractors Ltd | Construction | 2019 |
| Nestoak Limited | Households | 1990 |
| Neurodocs Limited | Health & social care | 2026 |
| New Forest Farms Limited | Agriculture & fishing | 2016 |
| New Friday Limited | Administrative & support | 2014 |
| New Globe (Malton) Ltd | Hospitality | 2022 |
| New Guard Holdings Limited | Wholesale & retail | 2016 |
| New Horizons Consultants Limited | Professional & scientific | 2020 |
| New Moonies Ltd | Hospitality | 2024 |
| Newbould Properties Ltd | Real estate | 2020 |
| Newco 321 Limited | Construction | 2022 |
| Newett (Annan) Limited | Real estate | 2024 |
| Newett (Hull) Limited | Construction | 2026 |
| Newett (Leven) Limited | Real estate | 2026 |
| Newett (Mines and Minerals) Limited | Real estate | 2024 |
| Newett Energy Limited | Energy | 2025 |
| Newett Estates Limited | Extraterritorial | 2018 |
| Newett Holdings Limited | Financial services | 2025 |
| Newett Homes (Birchencliffe) Limited | Real estate | 2025 |
| Newett Homes (Carcroft) Limited | Real estate | 2024 |
| Newett Homes (Emley) Ltd | Real estate | 2023 |
| Newett Homes (Fenay Bridge) Limited | Construction | 2022 |
| Newett Homes (Giggleswick) Limited | Real estate | 2024 |
| Newett Homes (Harrogate) Limited | Real estate | 2021 |
| Newett Homes (KIL) Ltd | Construction | 2026 |
| Newett Homes (Northowram) Ltd | Construction | 2023 |
| Newett Homes (P2) Ltd | Construction | 2026 |
| Newett Homes (Pontefract) Limited | Real estate | 2024 |
| Newett Homes (Pudsey) Limited | Real estate | 2023 |
| Newett Homes (Rossett Green) Limited | Construction | 2023 |
| Newett Homes Holdings Limited | Construction | 2021 |
| Newett Homes Investments Limited | Construction | 2019 |
| Newett Land Limited | Construction | 2018 |
| Newett Limited | Real estate | 2018 |
| Newett Minerals Limited Liability Partnership | | 2023 |