| Norsan Trans Ltd | Transport & logistics | 2018 |
| North and South Decorating Limited | Construction | 2021 |
| North Construction: Design & Build Limited | Professional & scientific | 2016 |
| North Degree Limited | Wholesale & retail | 2020 |
| North Gawber Colliery FC Ltd. | Arts & recreation | 2022 |
| North MID Fuels Limited | Wholesale & retail | 1992 |
| North Park (Rainsborough Park) Limited | Construction | 2026 |
| North Park (Woolley) Limited | Construction | 2026 |
| North Peak Consulting Limited | Professional & scientific | 2020 |
| North Star Estate Agents Limited | Real estate | 2008 |
| North Yorkshire Transmission Repairs Limited | Manufacturing | 2021 |
| Northern Aircraft Company Limited | Manufacturing | 2013 |
| Northern College for Residential Adult Education Limited(The) | Education | 1977 |
| Northern Heating & Solar Ltd | Construction | 2006 |
| Northern Interiors Ltd | Construction | 2018 |
| Northern Plumbing Supplies Ltd | Wholesale & retail | 2011 |
| Northern Project Solutions Ltd | Administrative & support | 2021 |
| Northern Regeneration CIC | Professional & scientific | 2015 |
| Northern Response Recovery Ltd | Wholesale & retail | 2026 |
| Northern Services Contracting Ltd | Construction | 2016 |
| Northern Services Limited | Real estate | 1981 |
| Northern Town Planning Ltd | Professional & scientific | 2018 |
| Northfield Partnership Ltd | Construction | 2014 |
| Northline Electric Ltd | Professional & scientific | 2026 |
| Northsouth Digital Ltd | Real estate | 2013 |
| Northspire Limited | Professional & scientific | 2023 |
| Nortonthorpe Heritage Mills Limited | Real estate | 2026 |
| NOT Another Syndicate Ltd | Arts & recreation | 2025 |
| Nottinghamshire Property Holdings Limited | Real estate | 2021 |
| Novalead Limited | Professional & scientific | 2016 |
| Novatrade Ventures Ltd | Wholesale & retail | 2026 |
| Noviu Ltd | Health & social care | 2023 |
| NOX Cleaner Air Solutions Ltd | Administrative & support | 2024 |
| Noyuki Limited | Health & social care | 2019 |
| NP Engineering Services Limited | Manufacturing | 2005 |
| NPC Couriers Limited | Transport & logistics | 2025 |
| NPR Brothers Ltd | Wholesale & retail | 2023 |
| NPR Construction Group Ltd | Construction | 2024 |
| Nqubekozolani Ltd | Wholesale & retail | 2018 |
| Nroute Limited | Transport & logistics | 2023 |
| NS Equestrian Ltd | Agriculture & fishing | 2022 |
| Nsmm Ltd | Information & communication | 2011 |
| NT CPE Limited | Education | 2025 |
| Ntlgov Ltd | Professional & scientific | 2024 |
| NTP Locks & Keys Ltd | Other services | 2025 |
| NTR Healthcare Recruitment Ltd | Other services | 2019 |
| NU Look Flooring Ltd | Wholesale & retail | 2012 |
| NU Look Partnership Limited | Real estate | 2023 |
| Nu-Build (Barnsley) Ltd | Real estate | 1985 |
| Nu-Lec Electrical Solutions Ltd | Construction | 2020 |
| Nu-Space Yorkshire Ltd | Real estate | 2018 |
| Nucare Empire Ltd | Professional & scientific | 2025 |
| Nucare Group Ltd | Health & social care | 2020 |
| Nucare Properties Ltd | Real estate | 2025 |
| Nudr Ltd | Manufacturing | 2025 |
| Number 15 Property Ltd | Real estate | 2024 |
| Number 38 Owners' Management Company Limited | Administrative & support | 2009 |
| Nungoz Health Care Limited | Agriculture & fishing | 2024 |
| Nurseryland Ltd | Wholesale & retail | 2007 |
| Nuut Sweets Ltd | Manufacturing | 2022 |
| Nuutology Ltd | Professional & scientific | 2021 |
| Nvdata Ltd | Information & communication | 2025 |
| NXA Spedition Ltd | Transport & logistics | 2021 |
| NYP Architectural Ltd | Professional & scientific | 2025 |
| Nyquist Solutions Limited | Information & communication | 1998 |
| Nyxbrands Ltd | Arts & recreation | 2023 |
| Nzeyi Ltd | Health & social care | 2026 |
| O'Brien Pipelines Limited | Energy | 2011 |
| O'Donnell Civil Engineers Ltd | Construction | 1997 |
| O'Donnell Estates Limited | Professional & scientific | 2007 |
| O'Donnell Housing Limited | Construction | 2018 |
| O'Donnell Management Company Limited | Professional & scientific | 2011 |
| O'Donnell Racing Limited | Agriculture & fishing | 2021 |
| O'Donnell Waste Management Ltd | Water & waste | 2011 |
| O'Shaughnessy Developments Ltd | Construction | 2025 |
| O.D.J Lifestyle&Fitness Ltd | Extraterritorial | 2020 |
| O.N.D. Limited | Construction | 1996 |
| OAB Property Ltd | Real estate | 2024 |
| Oak Car Wash Ltd | Wholesale & retail | 2025 |
| Oak Enterprises Hoyland Ltd | Hospitality | 2026 |
| Oak Forge Limited | Real estate | 2014 |
| Oak Grange Developments Limited | Real estate | 2018 |
| Oak House Nursery Limited | Education | 2005 |
| Oak Tree Commercial Ltd | Professional & scientific | 2026 |
| Oak Tree Developments (Yorkshire) Limited | Construction | 2010 |
| Oak Wood Early Years Ltd | Financial services | 2020 |
| Oakdale Accountancy Services Ltd | Professional & scientific | 2018 |
| Oakenshaw Healthcare Limited | Health & social care | 2021 |
| Oakfield Investment Group Ltd | Real estate | 2022 |
| Oaklea Sales & Lettings Ltd | Real estate | 2026 |
| Oakleigh Grange (Kendray) Management Company Limited | Professional & scientific | 2004 |
| Oakwell Car Sales T/A Carmakeover Barnsley Ltd | Wholesale & retail | 2025 |
| Oakwell Group Limited | Other services | 2012 |
| Oakwell Motor Homes Ltd | Wholesale & retail | 2006 |
| Oakwell Training Ltd | Education | 2020 |
| Oakwell Training Yorkshire CIC | Education | 2024 |
| Oakwells Corner Ltd | Wholesale & retail | 2026 |
| Oakwood Commercial Property Limited | Real estate | 2019 |
| Oakwood Doors & Spray Finishes Limited | Other services | 2008 |
| Oalus Limited | Administrative & support | 2008 |