| N.Vij Limited | Professional & scientific | 2016 |
| Nadine George Property Ltd | Real estate | 2022 |
| Naga Kitchen Limited | Hospitality | 2024 |
| NAM Electrical (UK) Ltd | Construction | 2019 |
| Naturandi RE Ltd | Other services | 2018 |
| NAV Trans Logistics Ltd | Transport & logistics | 2025 |
| Nawh Consulting Ltd | Other services | 2022 |
| NBH Scaffold Services Ltd | Construction | 2022 |
| NBS Property Investments Ltd | Real estate | 2020 |
| Nechitescu Trans Ltd | Transport & logistics | 2018 |
| NEG Construct Limited | Construction | 2023 |
| NEK Driving Services Ltd | Transport & logistics | 2017 |
| Neptune Business Consulting Ltd | Information & communication | 2021 |
| NET Zero Builds Limited | Manufacturing | 2024 |
| Network Team Ltd | Construction | 2006 |
| New Cabs & Co Ltd | Transport & logistics | 2018 |
| New Mercies Care Ltd | Health & social care | 2026 |
| New Ocean Glazing Limited | Construction | 2010 |
| New Punjab Coaches Limited | Transport & logistics | 1999 |
| Nextgen Constructions Group Limited | Construction | 2025 |
| NGH Limited | Real estate | 2024 |
| Nirab Solutions Ltd | Administrative & support | 2025 |
| Nitu Courier Ltd | Transport & logistics | 2021 |
| NM Garden Services Limited | Other services | 2012 |
| Noisy Software Ltd | Information & communication | 2021 |
| Nomad Electrical Ltd | Construction | 2016 |
| Nongpi International Limited | Professional & scientific | 2025 |
| Norfolk Close (Iver) Management Company Limited | Households | 2013 |
| Noriba Music Ltd | Information & communication | 2025 |
| Northern Star Lounge Ltd | Hospitality | 2025 |
| Nous Sommes Design Limited | Information & communication | 2007 |
| Nova Prime Construction Limited | Construction | 2026 |
| Noviv Limited | Transport & logistics | 2016 |
| Nowshesays Limited | Real estate | 2016 |
| NS2 Properties Ltd | Real estate | 2020 |
| Nutu Trans Ltd | Transport & logistics | 2017 |
| O.N Carpentry Limited | Construction | 2025 |
| Oakridge Commercial LLP | | 2010 |
| Oakwood Developments South East Limited | Construction | 2000 |
| Oakwood Parks Ltd | Hospitality | 2022 |
| Ocean Trailers Limited | Transport & logistics | 1990 |
| Octagon Business Capital Ltd | Real estate | 2019 |
| Oculus Security Limited | Administrative & support | 2016 |
| Offington Investments | Financial services | 2019 |
| Offington Resources | Mining & quarrying | 2019 |
| Oltanamax Ltd | Information & communication | 2023 |
| Omip Ltd | Information & communication | 2017 |
| Omvy Estates Limited | Real estate | 2024 |
| Onair Logistics Ltd | Wholesale & retail | 2025 |
| One Hype Limited | Professional & scientific | 2023 |
| Onestop Precision Engineering Ltd | Manufacturing | 2023 |
| Onyxo Limited | Wholesale & retail | 2019 |
| Oobie Creations Limited | Wholesale & retail | 2021 |
| Optimap Tuning Limited | Wholesale & retail | 2010 |
| Orange PMS Ltd | Construction | 2015 |
| Original Wooden Windows and Doors Limited | Construction | 2024 |
| Original Wooden Windows Limited | Manufacturing | 2007 |
| OS Agri Services Ltd | Administrative & support | 2024 |
| OSB Automotive Ltd | Wholesale & retail | 2019 |
| Overkill UK Limited | Information & communication | 1991 |
| Overseer Ltd | Information & communication | 2026 |
| P & D Conaty Limited | Professional & scientific | 1997 |
| P a ASK Properties Limited | Real estate | 2013 |
| P J Swallow Property Ltd | Real estate | 2024 |
| P&G Foods London Ltd | Wholesale & retail | 2025 |
| P&S Properties Limited | Real estate | 2022 |
| Pacifica Property Company Limited | Real estate | 2023 |
| Pack N Drop Ltd | Transport & logistics | 2025 |
| Palm Tree International Ltd | Information & communication | 2014 |
| Palm Tree Media Ltd | Information & communication | 2013 |
| Palm Tree Universal Limited | Professional & scientific | 2011 |
| Palm Tree Worldwide Limited | Professional & scientific | 2013 |
| Panache Limited | Real estate | 1997 |
| Panache Properties Limited | Real estate | 1981 |
| Panchakanya Ltd | Real estate | 2025 |
| Pandora’S Box Productions Ltd | Arts & recreation | 2024 |
| Panificio Italiano Limited | Manufacturing | 2016 |
| Park Lane Business Park Ltd | Real estate | 2023 |
| Parsonage Farm Management Company (1) Limited | Households | 2015 |
| Pasta DEL RE Ltd | Administrative & support | 2016 |
| Patelresidential Ltd | Real estate | 2021 |
| Paul Antony the Boutique Hair Salon Ltd | Other services | 2025 |
| Paul Baker Carpentry Ltd | Manufacturing | 2019 |
| Peakaboo Labels Ltd | Manufacturing | 2022 |
| Pearl Paradise Limited | Wholesale & retail | 2025 |
| Pegasus Union Ltd | Professional & scientific | 2012 |
| Penn Design Limited | Construction | 2012 |
| Penr Services Ltd | Information & communication | 2011 |
| Pet Auto Ltd | Transport & logistics | 2024 |
| Petal and Poppet Ltd | Wholesale & retail | 2025 |
| Phantom Coatings Limited | Wholesale & retail | 2023 |
| Phantom Estates Limited | Real estate | 2018 |
| Phenom Enterprises Limited | Real estate | 2019 |
| Physio Dynamix Ltd | Health & social care | 2003 |
| PIA Design Ltd | Professional & scientific | 2018 |
| Piantadosi - Zeno & Associates Law Consultancy Ltd | Professional & scientific | 2024 |
| Pillai's Foods Ltd | Wholesale & retail | 2020 |
| Pinewood Finco PLC | Administrative & support | 2017 |
| Pinewood Group Limited | Information & communication | 1999 |
| Pinewood South Limited | Real estate | 2020 |