| NAN Logistics Limited | Transport & logistics | 2017 |
| Nannies Foods Limited | Wholesale & retail | 2020 |
| Narcidan Transport Ltd | Transport & logistics | 2018 |
| Nash Chemists Ltd | Wholesale & retail | 2017 |
| Nash Engineering Ltd | Professional & scientific | 2015 |
| Nash Homecare Ltd | Health & social care | 2015 |
| Nash Mills Consulting Ltd | Information & communication | 2016 |
| Nash PUB Group Ltd | Hospitality | 2024 |
| Nast Corner Limited | Construction | 2022 |
| Natasha Thomas Limited | Professional & scientific | 2014 |
| Nati & Rebe Ltd | Transport & logistics | 2016 |
| National Demolition Training Group 2007 Limited | Education | 2007 |
| National Federation of Demolition Contractors Limited(The) | Other services | 1946 |
| National Piling and Groundworks Ltd | Construction | 2024 |
| Nationwide Water Products Ltd | Construction | 2016 |
| Nationwide Water Pumps Ltd | Construction | 2020 |
| Natural Resources (2000) Limited | Manufacturing | 1992 |
| Natural Wellbeing Spa Limited | Other services | 2023 |
| Nature for Kids Ltd | Education | 2021 |
| Navigation Management Limited | Professional & scientific | 2006 |
| Navigo Consulting Limited | Professional & scientific | 2020 |
| Nayax Capital UK Limited | Administrative & support | 2023 |
| Nayeemjamil Ltd | Health & social care | 2026 |
| NBM Technology Solutions Ltd | Wholesale & retail | 1988 |
| NBS Collections Limited | Information & communication | 2008 |
| NBS Investment Property Ltd | Households | 2022 |
| NCB Management Consultancy Ltd | Professional & scientific | 2021 |
| NCH Healthcare Services Limited | Health & social care | 2018 |
| NCM Enterprise Limited | Information & communication | 2014 |
| ND Squared Limited | Professional & scientific | 2015 |
| NDM Drywall Ltd | Construction | 2021 |
| Ndon Limited | Construction | 2025 |
| NEB Aesthetics Ltd | Other services | 2023 |
| NEC Software Solutions UK Limited | Information & communication | 1969 |
| Negretti & Zambra Limited | Extraterritorial | 1918 |
| Negretti Limited | Extraterritorial | 1936 |
| Neil @ Wren Designs Limited | Professional & scientific | 2018 |
| Neil Property Investments Ltd | Real estate | 2017 |
| Neil Stallard Property Services Limited | Real estate | 2013 |
| Neils Limited | Professional & scientific | 2002 |
| Neithal Ltd | Wholesale & retail | 2023 |
| Nespola Corp LLP | | 2024 |
| Nespola Holding Limited | Financial services | 2023 |
| Nespola Ltd | Wholesale & retail | 2021 |
| Nest Plan & Build Limited | Construction | 2022 |
| Nestar Limited | Wholesale & retail | 2023 |
| Nestle Residences Ltd | Real estate | 2024 |
| Netdeals Ltd | Wholesale & retail | 2025 |
| Nethermount Management Company Limited | Households | 2009 |
| Netronix Integration Limited | Administrative & support | 2015 |
| Network Billing Services Limited | Information & communication | 2003 |
| Network Digital Communications Limited | Information & communication | 2006 |
| Network Global Ltd | Professional & scientific | 2020 |
| Network Teachers Recruitment Ltd | Administrative & support | 2023 |
| Neuroinclusive Communities CIC | Professional & scientific | 2026 |
| Neurokinex CIC | Health & social care | 2012 |
| Neurokinex Performance Limited | Health & social care | 2013 |
| Neurovation Ltd | Administrative & support | 2020 |
| Neville Court Freehold Limited | Households | 2007 |
| New AGE Contractors Limited | Construction | 2015 |
| New Begin Ltd | Wholesale & retail | 2020 |
| New Chapter Tuition Ltd | Administrative & support | 2025 |
| New Curious Generation Limited | Professional & scientific | 2013 |
| New Curious Group Limited | Financial services | 2026 |
| New Foundations Homes Ltd | Real estate | 2023 |
| New Homes Ombudsman Service Limited | Public administration | 2021 |
| New Life Property Services Ltd | Real estate | 2022 |
| New Mogul Ltd | Hospitality | 2019 |
| New Page Services Ltd | Information & communication | 2023 |
| New Smart Technologies Ltd | Information & communication | 2025 |
| New South Lodge Limited | Real estate | 2020 |
| New Vision Effects Ltd | Administrative & support | 2019 |
| New Wine Rack Ltd | Wholesale & retail | 2017 |
| Newhall Resident Management Company Limited | Households | 2019 |
| Newquay View Resort Limited | Hospitality | 2013 |
| Next Level Swimming Academy Ltd | Education | 2020 |
| Next Level Swimming LLP | | 2021 |
| Next Thing Education Camps Ltd | Information & communication | 2018 |
| Next Thing Education Teachers Ltd | Professional & scientific | 2018 |
| Nextgenuity Ltd | Hospitality | 2023 |
| Nexus Construction Services Ltd | Professional & scientific | 2019 |
| Nexus Digital Limited | Professional & scientific | 2008 |
| Nexus Remediation Ltd | Professional & scientific | 2019 |
| NG Partners Ltd | Professional & scientific | 2013 |
| NG Project Ltd | Construction | 2024 |
| NG Services Ltd | Transport & logistics | 2025 |
| NHS Professionals Limited | Administrative & support | 2008 |
| Niall Ltd | Construction | 2023 |
| Nica Transport Limited | Transport & logistics | 2026 |
| Nice Thinking Strategy Ltd | Professional & scientific | 2019 |
| Nicholas James Fletcher Limited | Professional & scientific | 2004 |
| Nicholas James Mortgage & Financial Services Ltd | Financial services | 2014 |
| Nick JP Holdings Limited | Real estate | 2017 |
| Nick Media Limited | Professional & scientific | 2017 |
| Nicolas Plumbing Ltd | Construction | 2020 |
| Nidhi&Krishika Limited | Hospitality | 2025 |
| Nigel Baynes Limited | Professional & scientific | 2017 |
| Nigel Drake Limited | Professional & scientific | 2014 |
| Nightingale Close (Tring) Management Limited | Households | 2018 |
| Nightingale Fold Management Company Limited | Households | 2014 |