| Neuroptics Medical Ltd | Wholesale & retail | 2025 |
| Neuroworks Ltd | Health & social care | 2004 |
| Neville Villas RTM Company Limited | Administrative & support | 2015 |
| New Horizon Structures Ltd | Construction | 2023 |
| New Malden House Long Leasehold Limited | Real estate | 2017 |
| New Stone & Restoration Limited | Professional & scientific | 2022 |
| New Zealand Construction Limited | Construction | 2004 |
| Newlan Medical Ltd | Health & social care | 2012 |
| Newlands FH Limited | Financial services | 2025 |
| Nexgen Finance Ltd | Administrative & support | 2025 |
| Next Key Property Ltd | Real estate | 2026 |
| Niall Grimes Limited | Construction | 2011 |
| Niblock Logistic Solutions Limited | Transport & logistics | 2005 |
| Nicholls and SON Scaffolding Limited | Agriculture & fishing | 2019 |
| Nick Pruett Limited | Construction | 2014 |
| Nirvana Products Limited | Wholesale & retail | 2004 |
| Nivasa Limited | Real estate | 2025 |
| NJ Butchers Limited | Wholesale & retail | 2024 |
| Njpw Limited | Information & communication | 2008 |
| Node Control Ltd | Information & communication | 2026 |
| Nolva Ltd | Information & communication | 2025 |
| Norfloor Limited | Construction | 2005 |
| Norheads Residents Management Limited | Households | 2003 |
| North Downs Pet Care Ltd | Other services | 2014 |
| Northway Electrical Services Ltd | Construction | 2005 |
| Notably Country Ltd | Wholesale & retail | 2021 |
| Novo (75 HGR) Limited | Real estate | 2023 |
| Novo (Hilders Lane) Ltd | Real estate | 2022 |
| Novo (Roke Road) Ltd | Real estate | 2019 |
| Novo (Sutton) Ltd | Real estate | 2019 |
| Novo Building Services Ltd | Construction | 2019 |
| Novo Land & Development Ltd | Real estate | 2019 |
| Novo Planning LLP | | 2020 |
| NPY Legal Limited | Other services | 2023 |
| Nutritious Health Limited | Professional & scientific | 2014 |
| NW Commissioning Services Limited | Professional & scientific | 2007 |
| NW Training Ltd | Other services | 2026 |
| O'Malley Electrical Services Limited | Construction | 2014 |
| O'Rourke Enterprises Limited | Construction | 2003 |
| Oak Tree Construction of Sevenoaks Limited | Construction | 2010 |
| Oaklands Fire Ltd | Construction | 2020 |
| Oakwood Sales Ltd | Real estate | 2024 |
| Oasis Padel Ltd | Arts & recreation | 2025 |
| Ocean Breeze Charter Ltd | Arts & recreation | 2021 |
| Ocean Orange Ltd | Professional & scientific | 2022 |
| Ocular Property Limited | Real estate | 2015 |
| Odac Technology Ltd | Information & communication | 2025 |
| OEASE9 Ltd | Real estate | 2025 |
| Officialgmania Limited | Arts & recreation | 2014 |
| Old Spot Butchery Ltd | Wholesale & retail | 2025 |
| Olisa Consultancy Services Ltd | Professional & scientific | 2021 |
| Olisans Ltd | Wholesale & retail | 2024 |
| ON the FLI Management Ltd | Arts & recreation | 2023 |
| Onderwater Flowers Ltd | Wholesale & retail | 2019 |
| Only the Pillars Limited | Professional & scientific | 2025 |
| ONS Consulting Ltd | Professional & scientific | 2025 |
| Opal Aviation Limited | Transport & logistics | 1999 |
| Open View Surveying Ltd | Construction | 2025 |
| Optimum Homes Limited | Construction | 2004 |
| Options People Limited | Administrative & support | 2018 |
| Opus (South East) Limited | Administrative & support | 2010 |
| Orida Golf Ltd | Arts & recreation | 2023 |
| Orida Health Ltd | Health & social care | 2022 |
| Orida Hims Ltd | Hospitality | 2023 |
| Orida Hotels Ltd | Hospitality | 2021 |
| Orida Limited | Real estate | 2012 |
| Orida Newbury Ltd | Hospitality | 2024 |
| Oriens Aviation Limited | Wholesale & retail | 2015 |
| Oriens Aviation Services Limited | Extraterritorial | 2015 |
| Oriens Flight Operations Ltd | Wholesale & retail | 2015 |
| Oriens Holdings Limited | Wholesale & retail | 2018 |
| Oriens Maintenance Services Limited | Manufacturing | 2017 |
| Oros Education Ltd | Education | 2019 |
| OS Analytics Ltd | Information & communication | 2025 |
| Oshsafety Solutions Ltd | Professional & scientific | 2024 |
| Ostia Group Limited | Administrative & support | 2025 |
| Other Earth Ltd | Wholesale & retail | 2021 |
| OUR Business Club Ltd | Administrative & support | 2026 |
| OUR Group Limited | Professional & scientific | 2015 |
| OUR Logistics Limited | Professional & scientific | 2015 |
| OUR People Recruitment Limited | Administrative & support | 2017 |
| OUR Recruitment Limited | Administrative & support | 2017 |
| OUR Security Limited | Administrative & support | 2017 |
| Outdoors on the Downs Ltd | Arts & recreation | 2025 |
| Owentaylor Ltd | Construction | 2017 |
| Oxted & Limpsfield Barn Theatre Company Limited | Arts & recreation | 1923 |
| Oxted Commercial Property Limited | Real estate | 2022 |
| P a Rental Limited | Administrative & support | 2011 |
| P and C Landscapes Limited | Administrative & support | 2011 |
| P B Flooring Limited | Administrative & support | 2015 |
| P Boyle Haulage Limited | Transport & logistics | 2012 |
| P Clack Fencing Limited | Construction | 2006 |
| P H Works Limited | Professional & scientific | 2007 |
| P Newman Plumbing & Heating Services Limited | Other services | 2015 |
| P Steggle Associates Limited | Financial services | 2016 |
| P W Richards Developments Limited | Construction | 1999 |
| P-Paul Pools Limited | Administrative & support | 2015 |
| P3MO Consulting Limited | Professional & scientific | 2023 |
| PA Premier Build Limited | Construction | 2016 |
| Paar Group Ltd | Construction | 2022 |