| P R Drivers Ltd | Transport & logistics | 2020 |
| P R Sander Limited | Wholesale & retail | 1999 |
| P&C Executive Services Ltd | Administrative & support | 2020 |
| P.C.M. Electrical Limited | Construction | 1998 |
| P.Hunter,Limited | Administrative & support | 1947 |
| P.V.E. Construction Limited | Construction | 2005 |
| PAA Properties Ltd | Real estate | 2025 |
| Pack & Drive Limited | Transport & logistics | 2020 |
| PAI Healthcare Ltd | Public administration | 2018 |
| Pakistan Limited | Real estate | 2022 |
| Paliggenesia Limited | Administrative & support | 2023 |
| Palm Court Enterprises Ltd | Wholesale & retail | 2003 |
| Palm of Peace Ltd | Real estate | 2025 |
| Palm Prestige Ltd | Wholesale & retail | 2024 |
| Panda HAT Ltd | Information & communication | 2021 |
| Pangaea Technology Limited | Extraterritorial | 2002 |
| Paper Moon Construction Ltd | Information & communication | 2004 |
| Parabadu Design Limited | Professional & scientific | 1998 |
| Paradigmsix Ltd | Professional & scientific | 2014 |
| Parkfield Latimer Residents Limited | Households | 1987 |
| Parkfield Latimer Sports and Social Club Limited | Hospitality | 2022 |
| Parsec Innovation Limited | Financial services | 2024 |
| Partition Graphics Limited | Construction | 1998 |
| Partition Graphics London Limited | Construction | 2022 |
| Partner Project Management Ltd | Professional & scientific | 2026 |
| Passion for Food (2020) Ltd | Hospitality | 2015 |
| PAT Smith Environmental Ltd | Water & waste | 2018 |
| Pathfinder Technology Limited | Information & communication | 2020 |
| Patmos Consortium Limited | Professional & scientific | 2012 |
| Patmos Consulting (Global) Ltd | Professional & scientific | 2017 |
| Pattisson House LLP | | 2009 |
| Paul and Dragas Hair Studio Limited | Wholesale & retail | 2003 |
| Paul Reynolds Advisory Limited | Professional & scientific | 2026 |
| Paulexabeth Investments Limited | Real estate | 2010 |
| Pause Hertfordshire Limited | Wholesale & retail | 2017 |
| PAW and Stir Ltd | Wholesale & retail | 2024 |
| PCV Engineers Limited | Wholesale & retail | 2018 |
| PDA Electronics Ltd | Administrative & support | 1999 |
| Pdkb Limited | Professional & scientific | 2017 |
| Pebble Consult Limited | Professional & scientific | 2013 |
| Pegwyn Limited | Construction | 2001 |
| Pembi.Net Consulting Services Limited | Manufacturing | 2023 |
| Penn Landscapes Limited | Administrative & support | 2000 |
| Penn Roofing Services Limited | Construction | 2020 |
| Pennwords Limited | Administrative & support | 2019 |
| Pentaja Ltd | Transport & logistics | 2021 |
| Peponi Limited | Administrative & support | 2015 |
| Perception VFX Limited | Information & communication | 2021 |
| Perfect Pitch Ltd | Wholesale & retail | 2022 |
| Pergali Ventures Limited | Other services | 1997 |
| Peri Peri Chesham Ltd | Hospitality | 2019 |
| Peri Peri Chicken Original Ltd | Hospitality | 2025 |
| Perimitech Limited | Administrative & support | 1994 |
| Period Properties Ltd | Real estate | 2020 |
| Permasteel Limited | Construction | 2022 |
| Perryman Europe Ltd | Administrative & support | 2003 |
| Pet Health and Wellbeing Data & Analytics Ltd | Information & communication | 2024 |
| Peter Cherry Limited | Arts & recreation | 2006 |
| Peter Collins Coatings Consultancy Ltd | Professional & scientific | 2015 |
| Peter Sanders Photography Limited | Manufacturing | 1999 |
| Peter Simpson(Farms)Limited | Real estate | 1961 |
| Petergrace Property Solutions Ltd | Real estate | 2025 |
| Peterley Business Services Ltd | Professional & scientific | 2024 |
| PFC Financial Services Ltd | Financial services | 2023 |
| PFC Group Holdings Ltd | Financial services | 2019 |
| Phase Software Limited | Information & communication | 1984 |
| Phaser Regulatory Consulting Ltd | Professional & scientific | 2023 |
| Phasos Ltd | Hospitality | 2024 |
| Phaximed Limited | Wholesale & retail | 2016 |
| PHI Property Ltd | Hospitality | 2014 |
| Phil Dusek Limited | Administrative & support | 2017 |
| Philip Matthews Agricultural Contractors Limited | Agriculture & fishing | 2013 |
| Phillip Asos Ltd | Hospitality | 2024 |
| PHL Consultants Limited | Information & communication | 1997 |
| Phoenix Cretro Limited | Financial services | 2020 |
| Phoenix Roof Developments Ltd | Other services | 2021 |
| Phos Minimal Limited | Construction | 2021 |
| Pickwick Trading Limited | Professional & scientific | 2016 |
| Pictures UP Ltd | Information & communication | 2018 |
| Piercing Blue Ltd | Professional & scientific | 2012 |
| Piling Systems Ltd | Extraterritorial | 2015 |
| Pilling Investment and Holdings Ltd | Real estate | 2025 |
| Pink Bird Recording Co. Limited | Information & communication | 2016 |
| Pinkz Aesthetics Ltd | Extraterritorial | 2024 |
| Pinner Court Limited | Households | 1996 |
| Pioneer Regulatory Limited | Professional & scientific | 2018 |
| PIP Films CIC | Information & communication | 2021 |
| PIP in Amersham Ltd | Wholesale & retail | 2018 |
| Pipeline Technology Limited | Wholesale & retail | 1991 |
| Pipetech International Limited | Administrative & support | 2003 |
| Piping Hot (UK) Ltd | Construction | 2008 |
| Pippi's Pooch Boutique Ltd | Wholesale & retail | 2024 |
| PIT Bull Grips Ltd | Information & communication | 2024 |
| Pixel Info Ltd | Information & communication | 2023 |
| PK Cars Chesham Limited | Wholesale & retail | 2025 |
| PK Properties Investments Limited | Real estate | 2025 |
| Planctuary Limited | Professional & scientific | 2025 |
| Planet Innovative PVT Ltd | Hospitality | 2022 |
| Planet Wheels (High Wycombe) Limited | Professional & scientific | 2022 |
| Plasky Limited | Financial services | 2013 |