| Montgomery Bird Ltd | Wholesale & retail | 2019 |
| Montgomery House Limited | Real estate | 2019 |
| Moore Style (Richmond) Ltd | Other services | 2013 |
| Mooved UK Limited | Real estate | 2021 |
| Mother Shiptons Limited | Arts & recreation | 2011 |
| Motionprime Ltd | Transport & logistics | 2026 |
| Moyt Ltd | Information & communication | 2025 |
| MP Consulting Engineers (UK) Ltd | Professional & scientific | 2010 |
| MP Consulting Engineers Limited | Professional & scientific | 2007 |
| MR Garden and Grounds Services Ltd | Administrative & support | 2023 |
| Mummyfit (Harrogate) Ltd | Arts & recreation | 2019 |
| MVB Holdings Limited | Professional & scientific | 2015 |
| MWH Valeting Services Ltd | Administrative & support | 2022 |
| My Digital Concierge Ltd | Professional & scientific | 2021 |
| My JOB Trackr Ltd | Professional & scientific | 2026 |
| Mylearning Software Limited | Other services | 2023 |
| N.J. Batchelor Building Limited | Construction | 2003 |
| Naish Studio Ltd | Professional & scientific | 2022 |
| NAP Brands Limited | Wholesale & retail | 1981 |
| Nappa Car Park Management Limited | Real estate | 2014 |
| Nappa Investments Limited | Real estate | 2014 |
| Natal Angels Limited | Wholesale & retail | 2015 |
| Nataliya Wilson Foot Care Limited | Other services | 2014 |
| National Ohio Ltd | Real estate | 2024 |
| Natura Flooring Limited | Administrative & support | 2024 |
| Naylor Pharma Ltd | Wholesale & retail | 2019 |
| NDM Heath Ltd. | Professional & scientific | 2013 |
| NEO G Limited | Wholesale & retail | 2004 |
| Neotech Speciality Chemicals Ltd | Wholesale & retail | 2015 |
| Network Lighting (UK) Limited | Manufacturing | 2011 |
| Network Mapping Group Limited | Professional & scientific | 2011 |
| Network Mapping Limited | Professional & scientific | 2007 |
| Network Mapping UK Ltd | Professional & scientific | 2009 |
| New Taste 888 Ltd | Hospitality | 2023 |
| Newby James Ltd | Real estate | 2021 |
| Newmill Hospitality Ltd | Hospitality | 2019 |
| Newspaperman Ltd | Wholesale & retail | 2014 |
| Newton & Townend Limited | Construction | 2022 |
| Newton House Yorkshire Limited | Hospitality | 2012 |
| Newtons Conveyancing Limited | Professional & scientific | 2020 |
| Newtons Farms Limited | Agriculture & fishing | 2020 |
| Newtons Holdings Limited | Financial services | 2019 |
| Newtons Solicitors Ltd | Professional & scientific | 2009 |
| Nfldraftbuzz Ltd | Arts & recreation | 2022 |
| Nicole Everson Wealth Management Ltd | Financial services | 2017 |
| Nidd House Management Company Limited | Households | 2018 |
| Niddal Windows Limited | Construction | 1977 |
| Nidderdale Consulting Ltd | Administrative & support | 2024 |
| Nilo Investments Ltd | Construction | 2023 |
| Nimrod Housing Limited | Real estate | 2025 |
| Nixon Acquisitions Limited | Real estate | 2009 |
| Nomco 2000 Limited | Professional & scientific | 1999 |
| Nor-Rak Systems Ltd | Manufacturing | 2001 |
| Nord Kaffe Ltd | Wholesale & retail | 2025 |
| North Automotive Ltd | Wholesale & retail | 2025 |
| North South Connect Ltd | Transport & logistics | 2015 |
| North Vista Property Ltd | Real estate | 2022 |
| North West Property Sourcing Limited | Real estate | 2021 |
| North Yard Barbers Harrogate Ltd | Other services | 2026 |
| North Yorkshire Electric Bikes Ltd | Wholesale & retail | 2012 |
| Northern Digital Consultancy Limited | Information & communication | 2017 |
| Northern Digital Media Group Limited | Financial services | 2017 |
| Northern Digital Productions Limited | Manufacturing | 2017 |
| Northern Steel Installations Ltd | Construction | 2019 |
| Northwest Roofing Contractors Limited | Construction | 2026 |
| NPA Property Investments Limited | Extraterritorial | 2023 |
| Nu-Space Limited | Construction | 2000 |
| Number 21 Dragon Parade Maintenance Limited | Households | 1981 |
| NY Remedials Limited | Water & waste | 2025 |
| O a M Construction and Plant Hire Limited | Administrative & support | 2025 |
| O'Rourke Sports Limited | Information & communication | 2014 |
| O2 Consultants Ltd | Administrative & support | 2013 |
| Oak Door Ltd | Professional & scientific | 2020 |
| Oakara Living Limited | Construction | 2026 |
| Oakfield Development Services Limited | Professional & scientific | 2017 |
| Official Strongman Worldwide Ltd | Information & communication | 2018 |
| OIL Pollution, Environmental Control Limited | Wholesale & retail | 1980 |
| OJW Garden Services Limited | Administrative & support | 2026 |
| Old Chapel Consulting Ltd | Professional & scientific | 2019 |
| Old Tannery Management Company Limited | Households | 1983 |
| Oldstead Consultants Ltd | Professional & scientific | 2017 |
| Online Translation Services Limited | Professional & scientific | 2025 |
| Opec Limited | Real estate | 1995 |
| Opensoft Systems Limited | Professional & scientific | 2005 |
| Optimal Group Services Ltd | Construction | 2024 |
| Opulent Travel Ltd | Administrative & support | 2025 |
| Oracle Asset Finance Limited | Financial services | 2005 |
| ORB Community Enterprise | Health & social care | 2004 |
| Orbiton Ltd | Professional & scientific | 2026 |
| Orchard Grove (Knaresborough) Management Company Limited | Households | 2019 |
| Origin Healthcare Distribution Limited | Administrative & support | 2008 |
| Oscar & Clarke Ltd | Manufacturing | 2019 |
| OTC Healthcare Limited | Extraterritorial | 2022 |
| OUR News IS Your News Ltd | Information & communication | 2024 |
| Over the Rainbow Care Limited | Health & social care | 2014 |
| O’Brien Construction (Knaresborough) Ltd | Construction | 2019 |
| P & G Property Management Limited | Construction | 2020 |
| P G H Haulage Ltd | Transport & logistics | 2005 |
| P R Naylor Chemist Limited | Wholesale & retail | 2003 |
| P&S Maintenance & Gardening Ltd | Administrative & support | 2026 |