| MSC Lets Limited | Hospitality | 2025 |
| Multi-Let Area One Limited | Construction | 2015 |
| Muna Ltd | Hospitality | 2025 |
| Munro Building Services (South) Limited | Construction | 1959 |
| Munro Building Services Holdings Limited | Professional & scientific | 2015 |
| Munro Building Services Limited | Construction | 1990 |
| Murfin Joinery Limited | Construction | 2018 |
| My Delta Ltd | Professional & scientific | 2024 |
| Mystera Health Limited | Information & communication | 2021 |
| N C Van Sales Ltd | Wholesale & retail | 2019 |
| N D Spencer Investments Ltd | Real estate | 2015 |
| N180LK Limited | Financial services | 2025 |
| Nags Head Hulland Limited | Hospitality | 2024 |
| Nailers Management Company Ltd | Professional & scientific | 2022 |
| Nanrod Technical Services Ltd | Wholesale & retail | 2023 |
| Nash Service Centre Limited | Wholesale & retail | 2014 |
| Nathan Grace Holdings Limited | Professional & scientific | 2009 |
| Nathan LEE Artworks Ltd | Arts & recreation | 2018 |
| Naturally Flawless Aesthetics Limited | Health & social care | 2021 |
| Naturally Natal Limited | Health & social care | 2025 |
| Naturesworks Ltd | Professional & scientific | 2025 |
| Navigator IO Ltd | Education | 2024 |
| NC Car Solutions Ltd | Wholesale & retail | 2019 |
| NC Refurbs Limited | Wholesale & retail | 2025 |
| NC Van Refurbs Limited | Wholesale & retail | 2025 |
| NDC Properties Limited | Real estate | 2017 |
| NDC Quality Consulting Ltd | Professional & scientific | 2021 |
| Ndha Properties Limited | Financial services | 2023 |
| Neale Farms Limited | Agriculture & fishing | 1985 |
| Nebs Property Ltd | Real estate | 2021 |
| Neil Denton Rail Consultant Limited | Professional & scientific | 2021 |
| Nelson Investments Limited | Real estate | 2016 |
| Neutra Homes Ltd | Real estate | 2018 |
| New Leaf Homes Limited | Real estate | 2007 |
| New Oak Developments Ltd | Construction | 2007 |
| New Wish Enterprise Ltd | Wholesale & retail | 2021 |
| New Zealand Outfitters Limited | Agriculture & fishing | 2005 |
| Newbridge Ventures Ltd | Information & communication | 2021 |
| Newmoon Logistics Ltd | Transport & logistics | 2025 |
| Newtabb Consulting Limited | Professional & scientific | 2015 |
| Nicholas Charles Cars Limited | Wholesale & retail | 2017 |
| Nicholls Hydro Engineering Limited | Professional & scientific | 2014 |
| Nicholson Agencies Ltd | Wholesale & retail | 2014 |
| Nicholson Payroll Solutions Limited | Professional & scientific | 2009 |
| Nicholson Tax & Accounts Limited | Professional & scientific | 2009 |
| Nick Bannister Communications Limited | Professional & scientific | 2014 |
| Niko Comfort Keepers Ltd | Wholesale & retail | 2025 |
| NO.23 Limited | Professional & scientific | 2018 |
| NO.9 Leisure Limited | Wholesale & retail | 2004 |
| NO28 Belper Community Interest Company | Other services | 2024 |
| Norbury Futures Ltd | Real estate | 2023 |
| Norder Associates Limited | Professional & scientific | 2013 |
| Norder Design Associates Limited | Professional & scientific | 1975 |
| Norder Limited | Professional & scientific | 1994 |
| North Bear Media Ltd | Information & communication | 2024 |
| Northaxis Solutions Ltd | Information & communication | 2024 |
| Northfield House (Belper) Ltd | Construction | 2013 |
| Nouveau Derby Clinic Limited | Other services | 2023 |
| Nouveau Pathways CIC | Education | 2025 |
| Novametrics Limited | Professional & scientific | 2016 |
| NPO Productions Ltd | Arts & recreation | 2020 |
| NRB Accountancy Limited | Professional & scientific | 2015 |
| NRB Properties (Derbyshire) Limited | Real estate | 2017 |
| NSJ Family Investment Company Limited | Real estate | 2025 |
| Nuclear Collaboration Ltd | Professional & scientific | 2024 |
| Nugent Property Investments Ltd | Real estate | 2025 |
| Nytse Ltd | Health & social care | 2020 |
| Oakline Joinery Ltd | Construction | 2026 |
| Oaksys Tech Limited | Information & communication | 1998 |
| Ocean Crest Developments Limited | Construction | 2013 |
| Ocean Waves Catering Ltd | Hospitality | 2025 |
| Oceara Media Limited | Professional & scientific | 2025 |
| OEY Limited | Other services | 2020 |
| Offcote Limited | Real estate | 2016 |
| OH SO Sweet (RV) Ltd | Wholesale & retail | 2016 |
| Ohym Limited | Other services | 2023 |
| OJ & AH Supplies Limited | Wholesale & retail | 2015 |
| Old School Booth Ltd | Professional & scientific | 2020 |
| Olduns Ltd | Real estate | 2016 |
| Olivers Hair Studio Limited | Other services | 2022 |
| Ollie M Ltd | Professional & scientific | 2025 |
| Olney Associates Ltd | Other services | 2016 |
| Olson Handling Limited | Wholesale & retail | 2018 |
| Omeeto Group Ltd | Financial services | 2026 |
| Omeeto Holdings Ltd | Administrative & support | 2024 |
| Omeeto Ltd | Real estate | 2018 |
| Omo.Gifts Limited | Wholesale & retail | 2026 |
| ONLINE2DAY Ltd | Information & communication | 2026 |
| Onset Extras Ltd | Information & communication | 2014 |
| Oojit Ltd | Financial services | 2017 |
| Optimum Event Solutions Limited | Administrative & support | 2005 |
| Opus REI Group Limited | Professional & scientific | 2026 |
| Oracle Care and Education Holdings Limited | Health & social care | 2011 |
| Oracle Care Limited | Health & social care | 2005 |
| Ordinary OWL Limited | Wholesale & retail | 2020 |
| Orford & Partners Limited | Professional & scientific | 2021 |
| Orford Marine Limited | Wholesale & retail | 2023 |
| Organon Energy & Engineering Ltd | Professional & scientific | 2026 |
| Orthoped Ltd | Manufacturing | 2019 |
| Osiris Holdings Ltd | Financial services | 2020 |