| Nytram Gym Equipment Limited | Manufacturing | 2022 |
| O ' PEN Office Solutions Limited | Wholesale & retail | 2005 |
| O'Neill Flooring Solutions Ltd | Construction | 2023 |
| O.K.S Tran's'Ilesia Ltd | Transport & logistics | 2018 |
| Oak Tree Nursery School Fleetwood Limited | Health & social care | 2016 |
| Oakfield Country Holdings Ltd | Financial services | 2022 |
| Oakfield Saddlery Limited | Administrative & support | 2002 |
| Obsidian Holdings NW Ltd | Financial services | 2026 |
| Occam Software Ltd | Information & communication | 2025 |
| Ocean Team Holdings Limited | Other services | 2025 |
| ODP Care Limited | Health & social care | 2025 |
| Odyssey Motorhomes Ltd | Wholesale & retail | 2024 |
| OFFROAD4FUN Ltd | Wholesale & retail | 2021 |
| Offshore Cable Consultancy Limited | Energy | 2019 |
| Offshore Rigging Lifting and Personnel Services Ltd | Professional & scientific | 2024 |
| OG Films Ltd | Professional & scientific | 2023 |
| Ogden Design Consultants Limited | Construction | 2019 |
| Ogilvie Dogs Limited | Other services | 2017 |
| Ogilvie Properties Limited | Real estate | 2017 |
| OH Crumble Ltd | Hospitality | 2025 |
| OHN Boxing Management & Promotions Ltd | Administrative & support | 2020 |
| OHN Consultancy Ltd | Other services | 2018 |
| Oldar Fashion & Artwork Ltd | Wholesale & retail | 2025 |
| Oldar Transporting Ltd | Transport & logistics | 2024 |
| Olde English Contractors UK Ltd | Construction | 2022 |
| OM Premises Management Ltd | Hospitality | 2026 |
| One Call 4 Car Care Limited | Extraterritorial | 2008 |
| One Call Valeting Limited | Administrative & support | 2018 |
| One Two Agency Ltd | Administrative & support | 1988 |
| Online Car Parts Ltd | Wholesale & retail | 2015 |
| Online Dispensing Ltd | Wholesale & retail | 2025 |
| Online Interior Solutions Ltd | Wholesale & retail | 2018 |
| Only Skin Deep Ltd | Other services | 2017 |
| Onovo Ltd | Information & communication | 2025 |
| Ontouch Plastering & Rendering Ltd | Construction | 2025 |
| Onyx Training Club Limited | Arts & recreation | 2026 |
| Operation Florian Limited | Public administration | 2012 |
| Operion Systems Limited | Professional & scientific | 2025 |
| Opex Cleaner Ltd | Administrative & support | 2026 |
| Ophelia Consulting Ltd | Education | 2023 |
| Oprica Leyland Ltd | Hospitality | 2016 |
| Oprica Services Limited | Professional & scientific | 2026 |
| Optiml Limited | Wholesale & retail | 2026 |
| OR Renovations Ltd | Real estate | 2022 |
| Orchard Marl Ltd | Wholesale & retail | 2025 |
| Original Fitness NW Ltd | Arts & recreation | 2024 |
| Original Kebab House Ltd | Hospitality | 2020 |
| Orius Ltd | Wholesale & retail | 2019 |
| Oshi Organics Limited | Wholesale & retail | 2023 |
| Ospaka Ltd | Wholesale & retail | 2024 |
| OT Cyber Security Services Ltd | Administrative & support | 2025 |
| Otld Holdings Ltd | Financial services | 2023 |
| Outdoor Style Ltd | Wholesale & retail | 2022 |
| Ownly Digital Limited | Information & communication | 2026 |
| OXY Health Wellness Ltd | Health & social care | 2021 |
| Ozzy's Barber Leyland Ltd | Other services | 2024 |
| P a Cookson Limited | Construction | 2022 |
| P M Offshore Limited | Construction | 2023 |
| P Yates Builders Limited | Construction | 2019 |
| P.M.Wall Finishing Ltd | Construction | 2022 |
| Pados Services Ltd | Transport & logistics | 2025 |
| Paghman Etihad Ltd | Wholesale & retail | 2026 |
| Paintball Trax Ltd | Arts & recreation | 2009 |
| PAK Barna Ltd | Hospitality | 2019 |
| Pakistan Procurement Ltd | Agriculture & fishing | 2023 |
| Palm Court Care (Dawlish) Limited | Health & social care | 2015 |
| Palm Court Care (Holdings) Limited | Financial services | 2022 |
| Pamelia Coaching Ltd | Education | 2015 |
| Panoramic Group Holdings Ltd | Financial services | 2026 |
| Panoramic Property Developments Ltd | Real estate | 2026 |
| Pareto Consultancy Limited | Information & communication | 2000 |
| Parformancegolf Ltd | Arts & recreation | 2026 |
| Park House Consulting Solutions Ltd | Professional & scientific | 2026 |
| Parkinson Pets Ltd | Wholesale & retail | 2021 |
| Parts Genius Ltd | Wholesale & retail | 2019 |
| Parza Limited | Hospitality | 2025 |
| Pasteg Properties Ltd | Real estate | 2018 |
| Patel Foods Limited | Hospitality | 2019 |
| Path 2 Success Mentoring Limited | Professional & scientific | 2018 |
| Paul and Nanda Photography Ltd | Professional & scientific | 2025 |
| Paul Doran Limited | Real estate | 2011 |
| Paul Duckworth Ltd | Administrative & support | 2020 |
| Paul Fairhurst Ltd | Construction | 2012 |
| Paul Haylock Dog Training Ltd | Other services | 2025 |
| Paul J Lambert (Plumbing & Heating) Limited | Construction | 2013 |
| Paul's Farm Shop Limited | Wholesale & retail | 2001 |
| Paulco Limited | Real estate | 1994 |
| Paulo Alves Taklim Ferreira Ltd | Arts & recreation | 2026 |
| Pauls Farm and Fabrication Ltd | Agriculture & fishing | 2021 |
| Paulton Birch Ltd | Wholesale & retail | 2025 |
| PAV Automation Ltd | Information & communication | 2022 |
| Pavertec Limited | Administrative & support | 2004 |
| Paws Explore Ltd | Other services | 2026 |
| Payments Run Ltd | Administrative & support | 2021 |
| PC TH MG Properties Ltd | Real estate | 2024 |
| PCA Clinics Ltd | Health & social care | 2025 |
| Pembrey Tanager Ltd | Wholesale & retail | 2025 |
| Penelope’S Pet Food Ltd | Wholesale & retail | 2023 |
| Peony Box Limited | Wholesale & retail | 2019 |
| Pepik Trans Ltd. | Transport & logistics | 2018 |