| Ordman Medical Ltd | Health & social care | 2023 |
| Oriental Wisdom Limited | Real estate | 2003 |
| Orin Games Ltd | Information & communication | 2021 |
| Oroshiba Ltd | Wholesale & retail | 2025 |
| Orso Business Services Limited | Professional & scientific | 2018 |
| Orthopaedic HIP and Knee Solutions Ltd | Health & social care | 2012 |
| Orthopaedic Surgery Ltd | Health & social care | 2009 |
| Orthrus Holdings Ltd | Construction | 2018 |
| Oscar Oak Investments Limited | Financial services | 2021 |
| Oscar Oak Properties Limited | Real estate | 2025 |
| Oscar Properties Limited | Real estate | 2018 |
| Osgn Technologies Ltd | Information & communication | 2017 |
| OSS Interiors Ltd | Construction | 2006 |
| Ostpharma Limited | Wholesale & retail | 2011 |
| OT Plastering Ltd | Construction | 2022 |
| OTG Designs Ltd | Wholesale & retail | 2021 |
| Otilia's Homes Ltd | Real estate | 2025 |
| Ottawa House Ltd | Households | 2024 |
| Otterbourne Developments Limited | Construction | 2020 |
| OUR Turn Limited | Wholesale & retail | 2022 |
| Outreachuk Ltd | Professional & scientific | 2025 |
| Outstanding Collection Limited | Hospitality | 2025 |
| Outworks Finance Limited | Financial services | 2021 |
| Outworks Payroll Limited | Administrative & support | 2021 |
| Oven Steam Clean Ltd | Administrative & support | 2026 |
| Ovorda Ltd | Households | 2025 |
| Owls Hoot Media Limited | Professional & scientific | 2023 |
| Ozmutes Limited | Education | 2003 |
| P C Daruwalla Accountancy Limited | Professional & scientific | 2019 |
| P J Environmental Services Limited | Administrative & support | 2003 |
| P Landlords Ltd | Households | 2018 |
| P R Jain Limited | Health & social care | 2013 |
| P&F Building Service Limited | Construction | 2017 |
| P&P Arts & Entertainment Limited | Arts & recreation | 2025 |
| P&S Tailing Services Ltd | Construction | 2015 |
| P.F.J Pharma Consulting Ltd | Administrative & support | 2016 |
| P.M. Bar & Restaurant Ltd | Other services | 2025 |
| P.Rincemount (Trading) Ltd | Wholesale & retail | 2018 |
| P.Rincemount Trading ( Holdings) Ltd | Financial services | 2018 |
| P.S.A. Textiles Limited | Wholesale & retail | 2003 |
| P3 Electrical Services Ltd | Construction | 2014 |
| Paad Property Management Ltd | Real estate | 2026 |
| Packhurst Limited | | 1982 |
| Packify Ltd | Wholesale & retail | 2021 |
| PAD Haulage Ltd | Transport & logistics | 2022 |
| Padarthi Ltd | Information & communication | 2016 |
| Paddington Airport Transfers Limited | Transport & logistics | 2017 |
| Paddington Superstore Ltd | Wholesale & retail | 2019 |
| Paint and Play Limited | Other services | 2016 |
| Palapharm Limited | Wholesale & retail | 2023 |
| Palate on Wheels Limited | Hospitality | 2016 |
| Palatini Limited | Real estate | 1999 |
| Palermo Flat Management Company Limited | Real estate | 1981 |
| Palkhi Handicraft Limited | Wholesale & retail | 2024 |
| Palladium Products (UK) Limited | Wholesale & retail | 2018 |
| Pallum Health Ltd | Information & communication | 2025 |
| Palma Deli Ltd | Hospitality | 2018 |
| Panacea Health Medical Services Ltd | Health & social care | 2019 |
| Panache the Lounge Limited | Hospitality | 2011 |
| Panchal Associates Ltd | Professional & scientific | 2018 |
| Pancroft Limited | Wholesale & retail | 2006 |
| Pangaea Collection Ltd | Real estate | 2021 |
| Pangaea Event Limited | Professional & scientific | 2020 |
| Panjab Radio Group Ltd | Information & communication | 2019 |
| Pankhania Group Limited | Professional & scientific | 2015 |
| Panm Properties Limited | Real estate | 2021 |
| Pannenkoeken Flavour Limited | Hospitality | 2024 |
| Pannion Limited | Administrative & support | 2014 |
| Panta Real Estate Limited | Professional & scientific | 2024 |
| Panther 1 Limited | Real estate | 2015 |
| Pantiru Limited | Health & social care | 2019 |
| Papa Carlo Ltd | Manufacturing | 2023 |
| Paper Design Co Limited | Wholesale & retail | 2020 |
| Paradigm Health Ltd | Health & social care | 2015 |
| Paradigm Therapy Limited | Health & social care | 2015 |
| Paradise Management Limited | Real estate | 2006 |
| Paragliding.Community Limited | Other services | 2019 |
| Paragon Logistics Group Ltd | Transport & logistics | 2020 |
| Paramhansa Consulting Limited | Information & communication | 2026 |
| Parbrook Food Supply Limited | Wholesale & retail | 2024 |
| Parekh Properties Limited | Real estate | 2018 |
| Parin UK Ltd | Wholesale & retail | 2019 |
| Park House CH Limited | Health & social care | 2021 |
| Parkfields Investment Limited | Financial services | 2018 |
| Parkwood Property Consultants Ltd | Professional & scientific | 2025 |
| Parlay Media Group Ltd | Information & communication | 2008 |
| Party Magic Limited | Extraterritorial | 2014 |
| Pasha Property Rentals Limited | Real estate | 2019 |
| Pass (Leighton Road) Limited | Real estate | 2025 |
| Pass Woodlands Limited | Real estate | 2025 |
| Passive Fire Stopping Ltd | Administrative & support | 2022 |
| Passo Inc Limited | Real estate | 2019 |
| Patel Chaatwala Ltd | Hospitality | 2024 |
| Pathfinder Discovery Limited | Professional & scientific | 2025 |
| Pathma Properties Ltd | Real estate | 2026 |
| Pathwise Limited | Real estate | 1985 |
| Patisserie Brione London Ltd | Manufacturing | 2024 |
| Patria Evoo Ltd | Wholesale & retail | 2025 |
| Pattison Road Investors Limited | Construction | 2018 |
| Patwal Holdings Ltd | Real estate | 2016 |