| Newro Ltd | Other services | 2017 |
| Newstar Advisors Limited | Professional & scientific | 2025 |
| Newstate Limited | Professional & scientific | 2003 |
| Newstreamstudios Limited | Information & communication | 2021 |
| Newton Asset Limited | Hospitality | 2016 |
| Newton Automotive Limited | Manufacturing | 2005 |
| Newton Collins Engineering Limited | | 1987 |
| Newton Green Properties Limited | Real estate | 2002 |
| Newton Hotel Management Limited | Hospitality | 2016 |
| Newton Peacock Ltd | Real estate | 2022 |
| Newton Road Conservative Club,Limited(The) | Other services | 1902 |
| Newtown K Property Ltd | Real estate | 2025 |
| Nexadata Services Ltd | Administrative & support | 2025 |
| Nexalogix Ltd | Transport & logistics | 2025 |
| Nexavolt Ltd | Construction | 2025 |
| Nexbyte Consulting Limited | Information & communication | 2025 |
| Nexdive Ltd | Information & communication | 2025 |
| Nexio Digital Ltd | Information & communication | 2026 |
| Nexmove Solutions Limited | Professional & scientific | 2026 |
| Nexo AI Limited | Financial services | 2025 |
| Nexo People Limited | Administrative & support | 2025 |
| Next GEN Opti Ltd | Information & communication | 2014 |
| Next Level Visibility Ltd | Other services | 2025 |
| Nextgen Barberz Ltd | Other services | 2025 |
| Nextlevel Pro Ltd | Information & communication | 2018 |
| Nextpoint Innovations Limited | Administrative & support | 2023 |
| Nexus Creative Print Production Ltd | Manufacturing | 2018 |
| Nexus Systems Group Ltd | Financial services | 2023 |
| Neymar Super Ltd | Wholesale & retail | 2019 |
| Nfass Properties Ltd | Real estate | 2026 |
| NFS Transport Ltd | Transport & logistics | 2018 |
| NG Grace Trans Ltd | Transport & logistics | 2024 |
| NGC Autospares Ltd | Wholesale & retail | 2007 |
| Ngenuity Properties Ltd | Real estate | 2020 |
| NHD East Anglia Ltd | Construction | 2019 |
| NHD H & S Group Limited | Construction | 2024 |
| Nice & Spice Ltd | Hospitality | 2023 |
| Nice Bond Ltd | Real estate | 2022 |
| Nice Travel Solutions Ltd | Transport & logistics | 2015 |
| Nice Work Digital Limited | Professional & scientific | 2010 |
| Nicholas Jacob Architects LLP | | 2017 |
| Nicholas Sumner and Sons Ltd | Real estate | 2024 |
| Nicholls Limited | Water & waste | 2015 |
| Nicjon Ltd | Transport & logistics | 2016 |
| Nick Barber Architects Limited | Professional & scientific | 2014 |
| Nick Bray Geoservices Ltd | Construction | 2025 |
| Nick Cleaner Ltd | Administrative & support | 2026 |
| Nick Perlaki Services Limited | Administrative & support | 2025 |
| Nick Properties Limited | Real estate | 2023 |
| Nick's Automotive Paint Supplies Ltd | Wholesale & retail | 2018 |
| Nicky Wilson Properties Limited | Real estate | 2022 |
| Nicola White Sport Limited | Arts & recreation | 2017 |
| Nicot Moto Ltd | Wholesale & retail | 2022 |
| Nicots Healthcare Limited | Education | 2018 |
| Nicu’S Crystal Clean Ltd | Administrative & support | 2026 |
| Nidus Limited | Construction | 2008 |
| Niftysphere London Limited | Wholesale & retail | 2024 |
| Nigel Allison Ltd | Professional & scientific | 2002 |
| Nigel French & Associates Ltd | Professional & scientific | 2002 |
| Nigel Shaw Art Ltd | Arts & recreation | 2014 |
| Nightingale Associates Limited | Professional & scientific | 1994 |
| Nightingale Meadow (Leiston) Management Company Limited | Households | 2018 |
| NIKI95 Ltd | Transport & logistics | 2019 |
| Nikki Betts Ltd | Financial services | 2018 |
| Nikki's Accounting Limited | Professional & scientific | 2021 |
| Nikolao's Trans Limited | Transport & logistics | 2019 |
| Nikolas Estate Ltd | Health & social care | 2022 |
| Niksco Limited | Professional & scientific | 2025 |
| Nikstick Ltd | Professional & scientific | 2021 |
| Nikzcarhub Ltd | Wholesale & retail | 2025 |
| Nili Group Ltd | Health & social care | 2018 |
| Nilo Solutions Limited | Professional & scientific | 2018 |
| Nimbush International Limited | Wholesale & retail | 2016 |
| Ninedoors Ltd | Information & communication | 2023 |
| Nineteen-Twentyfour Clothing Ltd | Wholesale & retail | 2025 |
| Ninja PIG Ltd | Professional & scientific | 2018 |
| Nissi FS Ltd | Financial services | 2024 |
| NIX Consultancy Limited | Professional & scientific | 2022 |
| NJS Joinery Limited | Manufacturing | 2015 |
| NK Cooper Limited | Construction | 2016 |
| Nk&Sons Transport Ltd | Wholesale & retail | 2020 |
| NLC99 Limited | Arts & recreation | 2021 |
| NML Design Ltd | Professional & scientific | 2024 |
| NN07 UK Limited | Manufacturing | 2023 |
| NO Into YES Consultancy Ltd | Financial services | 2018 |
| NO.1 Timber Ltd | Wholesale & retail | 2019 |
| Nobilgroup Limited | Wholesale & retail | 2024 |
| Noble Hound Naturals Limited | Wholesale & retail | 2025 |
| Noble Wealth Holdings Limited | Administrative & support | 2005 |
| Nobleprinting Limited | Manufacturing | 2024 |
| Noerahm's Care Services Ltd | Health & social care | 2024 |
| Nomad Technologies UK Holdings Limited | Information & communication | 2022 |
| Nomad Ventures Limited | Arts & recreation | 2005 |
| Nomadic Wisdom AI Ltd | Administrative & support | 2025 |
| Nomadique Co Ltd | Wholesale & retail | 2025 |
| Nomia Law Limited | Professional & scientific | 2014 |
| Nominatis Limited | Professional & scientific | 2014 |
| NON Sequitur Ltd | Professional & scientific | 2011 |
| NON Stanford Limited | Arts & recreation | 2013 |
| Nonesuch Expeditions Limited | Information & communication | 1986 |