| Nouretech Ltd | Information & communication | 2026 |
| Nouveau Commercial Ltd | Professional & scientific | 2019 |
| Nouveau Fabrics Ltd | Manufacturing | 2019 |
| Nouveau Financial Limited | Financial services | 2018 |
| Nouveau FS Group Limited | Financial services | 2017 |
| Nouveau Wills & Estate Planning Limited | Professional & scientific | 2019 |
| Nova Assets Solutions Ltd | Real estate | 2025 |
| Nova's Autos Limited | Wholesale & retail | 2026 |
| Novailium Limited | Information & communication | 2025 |
| Novailium Software Solutions Limited | Information & communication | 2025 |
| Novale Impex LLP | | 2018 |
| Novaline Logistics Limited | Transport & logistics | 2025 |
| Novapaws Ltd | Wholesale & retail | 2026 |
| Novasphere Data Ltd | Extraterritorial | 2026 |
| Novavita Ltd | Construction | 2021 |
| Novello (UK) Limited | Other services | 2001 |
| Novena Health and Social Care Ltd | Health & social care | 2023 |
| Novenstra Ltd | Information & communication | 2025 |
| Noventra Holdings Ltd | Extraterritorial | 2026 |
| Novum Synergy Services Ltd | Wholesale & retail | 2024 |
| Novus 25 Limited | Wholesale & retail | 2019 |
| Novus 28 Limited | Extraterritorial | 2017 |
| Novus 7 Limited | Construction | 2026 |
| Novus Developments Limited | Real estate | 2005 |
| Novus Kitchens Limited | Manufacturing | 2023 |
| Novus Marketing Solutions Ltd | Professional & scientific | 2019 |
| Novuscasual Limited | Wholesale & retail | 2014 |
| Novyx Group Ltd | Extraterritorial | 2026 |
| NOW Placement Ltd | Other services | 2019 |
| Noxcuse Productions Limited | Information & communication | 2007 |
| NP Bandaru Limited | Health & social care | 2016 |
| NP Bespoke Tiling Ltd | Construction | 2021 |
| NP Property Services (UK) Ltd | Construction | 2014 |
| NPD E2E Consultancy Ltd | Health & social care | 2021 |
| NPM Building & Maintenance Ltd | Construction | 2017 |
| NPM Construction Doncaster Limited | Construction | 2021 |
| Npmzenith Limited | Construction | 2021 |
| NPR 21 Cleveland Freehold Limited | Real estate | 2025 |
| NPR 21 Cleveland Lettings Limited | Real estate | 2025 |
| NPR Danum Freehold Limited | Real estate | 2025 |
| NPR Danum Lettings Limited | Real estate | 2025 |
| NPR Portfolio Limited | Real estate | 2023 |
| NPS Mechanical Limited | Construction | 2022 |
| NS Concepts Ltd | Information & communication | 2018 |
| Ns-Isc Limited | Information & communication | 2006 |
| NSD Direct Logistic Limited | Transport & logistics | 2018 |
| Nsmpropertiess Ltd | Real estate | 2021 |
| Nsr.Consultancy Ltd | Information & communication | 2021 |
| Nssc Group Ltd | Hospitality | 2024 |
| Nstrouk Limited | Arts & recreation | 2026 |
| NSW Developers Ltd | Real estate | 2020 |
| NT Property Limited | Real estate | 2019 |
| NTJ Consulting Ltd | Construction | 2023 |
| NTR Falcons Limited | Agriculture & fishing | 2019 |
| Ntuk Technology Ltd | Information & communication | 2020 |
| NU Clinical Aesthetics Limited | Health & social care | 2019 |
| Nu-Openings Holdings Limited | Financial services | 2021 |
| Nu-Openings Limited | Construction | 2009 |
| Nublu Holding Limited | Financial services | 2024 |
| Numae Ltd | Wholesale & retail | 2025 |
| Number 1 CUT Limited | Other services | 2025 |
| Number 6 Films Ltd | Information & communication | 2023 |
| Number One Law LLP | | 2008 |
| Number One Super Convenience Stores Ltd | Wholesale & retail | 2012 |
| NUMBER1 Communications Ltd | Information & communication | 2018 |
| NUMBER1 Power Ltd | Construction | 2024 |
| Numbers Talk Ltd | Professional & scientific | 2020 |
| Numero Accountants Limited | Professional & scientific | 2005 |
| NUR Restaurant (Doncaster) Ltd | Hospitality | 2016 |
| Nurture Health Limited | Health & social care | 2021 |
| Nurtureline Ltd | Health & social care | 2026 |
| NUT Home Ltd | Financial services | 2026 |
| Nutridyn U.K. Ltd | Wholesale & retail | 2021 |
| Nutritional Harmony Limited | Hospitality | 2024 |
| Nutritiously Naked Ltd | Extraterritorial | 2018 |
| Nutrixor Limited | Health & social care | 2024 |
| Nutwell Land Limited | Professional & scientific | 2011 |
| Nutwood House Racing Ltd | Agriculture & fishing | 2025 |
| Nutwood Works Ltd | Real estate | 2021 |
| Nuvanta Systems Ltd | Extraterritorial | 2026 |
| Nval Consulting Ltd | Information & communication | 2025 |
| NW IT Services (UK) Limited | Information & communication | 2012 |
| NWA UK Limited | Construction | 2024 |
| Nwafo Media Limited | Information & communication | 2022 |
| NXN Consult Ltd | Professional & scientific | 2026 |
| NXT GEN Civil Engineering Limited | Construction | 2019 |
| NXT LVL Flooring & Interiors Ltd | Construction | 2023 |
| NY Management Services Ltd | Construction | 2013 |
| Nyazee Healthcare Ltd | Health & social care | 2025 |
| Nybor Limited | Administrative & support | 2010 |
| Nyny Ecom Ltd | Information & communication | 2026 |
| Nyovi Studios Ltd | Wholesale & retail | 2025 |
| O C Motor Repair Limited | Wholesale & retail | 2007 |
| O&B Limited | Health & social care | 2014 |
| O&N Property Solutions Limited | Real estate | 2025 |
| O&S Transport Ltd | Transport & logistics | 2025 |
| O'Blits Services Ltd | Extraterritorial | 2024 |
| O'Grady Creations Ltd | Manufacturing | 2015 |
| O'Hara Design Limited | Other services | 2007 |
| O'Hare Civils Limited | Construction | 2014 |