| Nursery Room Ltd | Education | 2018 |
| Nurture Springs Limited | Health & social care | 2024 |
| NVN Construction Ltd | Construction | 2020 |
| NW2WARRIORSFC Ltd | Arts & recreation | 2025 |
| NY Services Ltd | Hospitality | 2024 |
| NYN Food Services Ltd | Manufacturing | 2021 |
| O J London Property Services Limited | Real estate | 2025 |
| Oakstone Financial Services Limited | Financial services | 2026 |
| Oakwood Interior Solutions Ltd | Construction | 2009 |
| Oakworth Financial Limited | Professional & scientific | 2010 |
| OB World Trading Company Limited | Wholesale & retail | 2025 |
| Obaz Enterprise Ltd | Wholesale & retail | 2020 |
| Obeliver Drinks Limited | Manufacturing | 2012 |
| Obenson Capital Ltd | Financial services | 2024 |
| OBO Plastering Ltd | Construction | 2014 |
| Ocean City K & Y Ltd | Hospitality | 2015 |
| Ocean City Welling Limited | Hospitality | 2024 |
| Offbrand Media Ltd | Information & communication | 2024 |
| Offset Relief Ltd | Information & communication | 2026 |
| Ofma Educational Foundation | Education | 2016 |
| OG Transport Limited | Transport & logistics | 2025 |
| OH Care Service Limited | Health & social care | 2019 |
| OJ Supply Co Ltd | Wholesale & retail | 2026 |
| OJS Property Services Ltd | Construction | 2024 |
| Old York Limited | Construction | 2021 |
| Olives Healthcare Services Ltd | Administrative & support | 2020 |
| Omarth Global Limited | Information & communication | 2026 |
| OMD Solutions Ltd | Wholesale & retail | 2023 |
| Omnia ID Limited | Extraterritorial | 2012 |
| Omotayo & Sons Limited | Construction | 2020 |
| Omstan Limited | Other services | 2007 |
| Oneshot Services Ltd | Construction | 2013 |
| Onkaar Home Solutions Limited | Real estate | 2013 |
| Onyx Mortgage Finance Limited | Financial services | 2026 |
| Onyx SVR Ltd | Construction | 2014 |
| Opal RKB Ltd | Construction | 2015 |
| Opedare Investments Ltd | Real estate | 2021 |
| Opia Films Limited | Information & communication | 2016 |
| Optimus Brickpoint & Paints Ltd | Construction | 2025 |
| Opulent Flow Ltd | Hospitality | 2023 |
| Orangejbm Ltd | Real estate | 2024 |
| Organic Veggie Vibes Limited | Wholesale & retail | 2024 |
| Osama Pharma Ltd | Manufacturing | 2025 |
| Osiris Medical Services Limited | Health & social care | 2021 |
| Osmeco Limited | Administrative & support | 2023 |
| OTF Productions Ltd | Information & communication | 2026 |
| Oudavoir Ltd | Extraterritorial | 2025 |
| Outsorz Ltd | Information & communication | 2024 |
| Overflow Holdings Ltd | Financial services | 2022 |
| Oxleas Project Management Ltd | Professional & scientific | 2021 |
| P & L Restoration Services Ltd | Administrative & support | 2018 |
| P.Coker Estates Ltd | Real estate | 2025 |
| P.R. Freddi Ltd. | Construction | 1997 |
| Padeli Ltd | Wholesale & retail | 2022 |
| Pakholiuksdesing Limited | Construction | 2025 |
| Palmis Global Ltd | Wholesale & retail | 2024 |
| Panas Sushi Falconwood Ltd | Hospitality | 2024 |
| Panta Business Advisors Ltd | Professional & scientific | 2011 |
| Paper Wonder Cards Ltd | Wholesale & retail | 2026 |
| Papi Cubano Ltd | Other services | 2023 |
| Paraunity Exchange Ltd | Information & communication | 2025 |
| Parkyns Building Services Ltd | Construction | 2013 |
| Part Time Gaming Limited | Wholesale & retail | 2024 |
| Paru's Beauty Therapy Ltd | Other services | 2015 |
| PASS11.PLUS Limited | Information & communication | 2025 |
| Pathway EDU Ltd | Information & communication | 2026 |
| Pathway to Hope Services Ltd | Hospitality | 2025 |
| Paton Plumbing & Heating Solutions Limited | Construction | 2023 |
| Patrian Limited | Administrative & support | 2021 |
| Paul Varache Ltd | Information & communication | 2020 |
| PAV Beauty & Barber Ltd | Other services | 2019 |
| Pawsome Cozy Ltd | Wholesale & retail | 2025 |
| PD Design Production Limited | Manufacturing | 2017 |
| PDD Prime Device Ltd | Manufacturing | 2025 |
| Pejucare Services Limited | Health & social care | 2025 |
| Peniel Enterprises Ltd | Real estate | 2023 |
| Pentagon Roofing Ltd | Construction | 2018 |
| Pepa Developments Ltd | Construction | 2026 |
| Pepi Balkan Food Ltd | Wholesale & retail | 2025 |
| PER Excellence Education Center Ltd | Education | 2016 |
| Perfect Odd's Limited | Real estate | 2025 |
| Perfect Plastering London Ltd | Construction | 2021 |
| Perioperative Partners Ltd | Health & social care | 2018 |
| Perlin Developments Ltd | Administrative & support | 2015 |
| Personalised Pretties Ltd | Wholesale & retail | 2021 |
| Pets Come First Limited | Agriculture & fishing | 2022 |
| PGN Building Services Ltd | Construction | 2025 |
| PHASE1 Electrical & Building Services Limited | Construction | 2026 |
| Phecoria Company Limited | Administrative & support | 2009 |
| Phoenix Graphic Application Ltd | Administrative & support | 2008 |
| Phoenix Pharma Group Ltd | Agriculture & fishing | 2025 |
| Phone Deal Ltd | Wholesale & retail | 2020 |
| Picknbuy Ltd | Wholesale & retail | 2024 |
| Pineleaf Consulting Limited | Professional & scientific | 2015 |
| Pioneer Carpentry & Building Limited | Construction | 2015 |
| Pixelpro Solutions Ltd | Information & communication | 2023 |
| Pizza Tonight Welling Ltd | Hospitality | 2026 |
| PL Tech Ltd | Administrative & support | 2025 |
| Planik Limited | Information & communication | 2026 |
| Plasteringsoutheastlondon Ltd | Construction | 2025 |