| P I R Limited | Administrative & support | 1993 |
| P K R Plumbing & Heating Limited | Construction | 2011 |
| P R S Electrical Services Limited | Construction | 2006 |
| P.K. Catering (UK) Limited | Hospitality | 2003 |
| P.T.Thaicharoen Limited | Hospitality | 2025 |
| Palm Studios Creative Ltd | Administrative & support | 2022 |
| Palmer Steel Ltd | Manufacturing | 2012 |
| Palmer Welding Ltd | Manufacturing | 2024 |
| Pantheon Engineering Ltd | Professional & scientific | 2013 |
| Paper Haveli Ltd | Wholesale & retail | 2006 |
| Paperclick UK Limited | Administrative & support | 2021 |
| Park Farm Chrishall Limited | Administrative & support | 2020 |
| Park Farm Forest School Limited | Education | 2025 |
| Park Hill Homes (UK) Limited | Construction | 2002 |
| Park Hill House Limited | Construction | 2004 |
| Parkstone Waste Management Limited | Water & waste | 2024 |
| Parquez Development Ltd | Construction | 2015 |
| Parthian Climbing Limited | Arts & recreation | 2003 |
| Parvati Health Ltd | Health & social care | 2024 |
| Passivhaus Homes Ltd. | Construction | 2008 |
| Paul Bates Plastering Limited | Construction | 2005 |
| Paul Moran Limited | Professional & scientific | 2004 |
| Paxmader Ltd | Manufacturing | 2023 |
| Paydo Holding Ltd | Financial services | 2024 |
| PBH Accounting Limited | Professional & scientific | 2012 |
| PBX Advisors Ltd | Administrative & support | 2019 |
| PCH Associates Limited | Professional & scientific | 2012 |
| PCH Associates Trustees Limited | Professional & scientific | 2025 |
| Peak Pawformance Ltd | Other services | 2026 |
| Peaker Pattinson & Company Limited | Wholesale & retail | 1996 |
| Pearl Pictures Limited | Professional & scientific | 2008 |
| Peat Motion Limited | Extraterritorial | 2021 |
| Peawise Ltd | Agriculture & fishing | 2015 |
| Pelham Autos Limited | Wholesale & retail | 2020 |
| Pelham Structures Limited | Construction | 1993 |
| Pellys Solicitors Limited | Professional & scientific | 2010 |
| Penguin Photography Limited | Professional & scientific | 1997 |
| Penleigh Search Limited | Administrative & support | 2019 |
| Penning Plumbing & Heating Ltd | Construction | 2016 |
| Penny Morrison Ltd | Professional & scientific | 2018 |
| Pension Helper Ltd | Professional & scientific | 2024 |
| Pentacle IT Limited | Information & communication | 2019 |
| People Plan Ltd | Professional & scientific | 2012 |
| Peperina Limited | Real estate | 2022 |
| Pepper Group Limited | Hospitality | 2016 |
| Perform Digital Limited | Professional & scientific | 2019 |
| Performium Consulting Limited | Professional & scientific | 2015 |
| Perioc Limited | Professional & scientific | 2012 |
| Pest Control 24SEVEN Ltd | Extraterritorial | 2011 |
| Peter Kaemer Consultancy Services Ltd | Professional & scientific | 2011 |
| Peter Stocking Project Services Ltd | Construction | 2023 |
| Peter Taylor & Partners Limited | Construction | 2002 |
| Peterborough and Cambridge Business Development Company Limited | Manufacturing | 2019 |
| Peterborough Properties Limited | Construction | 2013 |
| Petro People Training Limited | Administrative & support | 2021 |
| Pflare Ltd | Administrative & support | 2016 |
| Pgsc Consultancy Ltd | Transport & logistics | 2021 |
| Pharmacell Medication Systems Limited | Manufacturing | 2015 |
| Phase 5 Project Management Limited | Professional & scientific | 2003 |
| Phazed Creative Ltd | Information & communication | 2011 |
| PHNO24 Ltd | Real estate | 2017 |
| Phoenixchangeworks Ltd | Wholesale & retail | 2026 |
| Phosphor Consultancy Limited | Administrative & support | 2015 |
| Pickle ME Silvers Ltd | Information & communication | 2021 |
| Picture Studios Limited | Other services | 2006 |
| Picualia Limited | Wholesale & retail | 2016 |
| PIN and Play Limited | Information & communication | 2008 |
| Pine House Group Ltd | Professional & scientific | 2016 |
| Pink HOP Ltd | Hospitality | 2011 |
| PIR International Group Limited | Financial services | 2021 |
| PIVOT360 Ltd | Other services | 2020 |
| Pivotell Limited | Health & social care | 2002 |
| Pixcel Media Limited | Professional & scientific | 2019 |
| Pixies Holdings Limited | Financial services | 2024 |
| PJP Consulting Limited | Professional & scientific | 2017 |
| PJW Consult Ltd | Construction | 2025 |
| Plan IT Mortgages Limited | Financial services | 2025 |
| Planet Scuba School Ltd | Education | 2017 |
| Planning Control Limited | Professional & scientific | 2020 |
| Plastic Free Plants Ltd | Wholesale & retail | 2020 |
| Playsongs Publications Limited | Administrative & support | 2002 |
| Pledgdon Developments Ltd | Construction | 2022 |
| Plextek Holdings Limited | Professional & scientific | 2015 |
| Plextek Limited | Professional & scientific | 1988 |
| Plextek Services Limited | Professional & scientific | 2015 |
| Plotters Table Ltd | Hospitality | 2016 |
| Plough Ridge Limited | Construction | 2025 |
| Plusfile + Limited | Manufacturing | 2020 |
| Pluvo Limited | Professional & scientific | 2018 |
| Pmsi Strategy LLP | | 2014 |
| Point Master (UK) Limited | Manufacturing | 2006 |
| Pointfinder Limited | Real estate | 2013 |
| Polar Scientific Limited | Professional & scientific | 2013 |
| Polytechsolutions Limited | Wholesale & retail | 2013 |
| Pond Farm Limited | Agriculture & fishing | 2017 |
| Ponton Media Ltd | Information & communication | 2021 |
| Popple Projects Limited | Wholesale & retail | 2004 |
| Porchester Homes Ltd | Real estate | 2020 |
| Portman (Saffron Walden) Management Company Limited | Households | 1982 |
| Poseidon Acquisitions Ltd | Wholesale & retail | 2024 |