| Primekey Property Ltd | Real estate | 2023 |
| Primelo Limited | Information & communication | 2018 |
| Primemed Services Ltd | Health & social care | 2024 |
| Primeshift Consulting Ltd | Professional & scientific | 2019 |
| Primesphere Consulting Limited | Professional & scientific | 2013 |
| Primetime Construction Development Ltd | Construction | 2015 |
| Primevolt Installation Services Ltd | Construction | 2026 |
| Primex Property Services & Management Ltd | Transport & logistics | 2025 |
| Primier UK Trading Ltd | Wholesale & retail | 2025 |
| Primvara Limited | Arts & recreation | 2021 |
| Prince Capital Limited | Financial services | 2017 |
| Princeton & Co Care Services Limited | Real estate | 2021 |
| Princeton & Co Properties Limited | Real estate | 2026 |
| Principal Signs Limited | Administrative & support | 2005 |
| Prinik Properties Ltd | Real estate | 2019 |
| Prinju Enterprise Limited | Transport & logistics | 2022 |
| Prinkaf & Co Ltd | Wholesale & retail | 2015 |
| Prinsen U.K. Limited | Other services | 1995 |
| Printercartridge Recycling Ltd | Wholesale & retail | 2017 |
| Printnode Holdings Limited | Information & communication | 2014 |
| Printnode Limited | Information & communication | 2016 |
| Prints to the People Ltd | Wholesale & retail | 2023 |
| Priory Court Bradwell Abbey Management Limited | Real estate | 2010 |
| Priory Gate Hillingdon Management Company 1 Limited | Other services | 2000 |
| Priory Maintenance Limited | Health & social care | 2017 |
| Priory Mews (Newport Pagnell) Residents Management Company Limited | Households | 2017 |
| Priory Stone Limited | Administrative & support | 2022 |
| Priru Limited | Health & social care | 2021 |
| Prisaboat Limited | Health & social care | 2019 |
| Priscilla Foods Ltd | Wholesale & retail | 2008 |
| Priscilla's Aesthetics Limited | Health & social care | 2013 |
| Pristine Alloy Wheel Refurbishers Limited | Real estate | 1991 |
| Pristine Cleaning 4 U Ltd | Administrative & support | 2024 |
| Pristine Property Cleaning Ltd | Manufacturing | 2026 |
| Pristine Property Rentals Ltd | Real estate | 2018 |
| Pristine Property Services (Milton Keynes) Ltd | Construction | 2014 |
| Pristine Xtra Ltd | Administrative & support | 2026 |
| Pritesh Patel Digital Marketing Ltd | Information & communication | 2013 |
| Prithvi Management & Consultants Limited | Real estate | 2021 |
| Private Events Group Ltd | Hospitality | 2022 |
| Private Gynaecological Services Limited | Health & social care | 2010 |
| Privent Ltd | Information & communication | 2026 |
| Privilege Car Club Ltd | Administrative & support | 2017 |
| Privine Limited | Transport & logistics | 2014 |
| Privine Property Investments Ltd | Households | 2021 |
| Priya Technologies Ltd | Information & communication | 2011 |
| Prized Pads Ltd | Real estate | 2024 |
| Prlink Ltd | Information & communication | 2021 |
| Pro Certs Software Ltd | Information & communication | 2011 |
| Pro Electrical Marine Ltd | Manufacturing | 2025 |
| Pro Electrical MK Ltd | Construction | 2024 |
| Pro Environment Ltd | Construction | 2023 |
| Pro EVO Taxis Ltd | Transport & logistics | 2023 |
| Pro I Solutions Limited | Information & communication | 2019 |
| Pro Property Management Ltd | Real estate | 2024 |
| Pro Rads Limited | Health & social care | 2019 |
| Pro-Cafe CMK Ltd | Hospitality | 2025 |
| Pro-Cut Precision Engineering Limited | Manufacturing | 2010 |
| Pro-Projects Limited | Construction | 2025 |
| Pro-Safety Solutions PVT Ltd | Health & social care | 2011 |
| Proact Carpet Cleaning Limited | Extraterritorial | 2017 |
| Proact Pest Control Limited | Extraterritorial | 2017 |
| Proact Support Services Limited | Extraterritorial | 2017 |
| Proaction Networks Limited | Information & communication | 2008 |
| Proactive Facilities Group Ltd | Real estate | 2026 |
| Proagilityai Ltd | Information & communication | 2022 |
| Proall UK Limited | Manufacturing | 2018 |
| Probably a PUB Company Limited | Hospitality | 1999 |
| Probe Transport Solutions Limited | Transport & logistics | 2003 |
| Probity Clinical and Care Services Limited Limited | Health & social care | 2020 |
| Probuild Dynamics Limited | Real estate | 2016 |
| Processfix Ltd | Professional & scientific | 2005 |
| Prococktails Limited | Administrative & support | 2018 |
| Proconstruct Solutions Limited | Professional & scientific | 2013 |
| Procur International Holdings Limited | Professional & scientific | 2019 |
| Procur International Limited | Professional & scientific | 2015 |
| Procurelab Limited | Professional & scientific | 2025 |
| Procurevis International (UK) Ltd | Professional & scientific | 2014 |
| Prodaptix Ltd | Information & communication | 2025 |
| Prodeo Construct Ltd | Construction | 2019 |
| Product Pro Limited | Wholesale & retail | 2017 |
| Product Solutions Consulting Ltd | Information & communication | 2024 |
| Proeconomy Holdings Limited | Financial services | 2023 |
| Proeconomy Limited | Water & waste | 1993 |
| Professional Clothing Industry Association Worldwide Ltd | Other services | 2017 |
| Professional Energy Services Limited | Professional & scientific | 1992 |
| Professional Financial Care Limited | Financial services | 2010 |
| Professional Fulfilment Services Limited | Administrative & support | 2008 |
| Professional IT (MK) Limited | Information & communication | 2011 |
| Professional Land Surveys Ltd | Professional & scientific | 2017 |
| Professional Media Transport Guild Limited | Other services | 2016 |
| Professional Services IT Limited | Information & communication | 2016 |
| Professional Solutions Consulting Ltd | Information & communication | 2010 |
| Professional Steam Cleaning Ltd | Administrative & support | 2023 |
| Professional Towing & Support Services Limited | Transport & logistics | 2021 |
| Profitum Ltd | Professional & scientific | 2019 |
| Profix Connect Ltd | Wholesale & retail | 2024 |
| Profix Facade Ltd | Construction | 2022 |
| Prognostix-Poultry Limited | Professional & scientific | 2019 |
| Progression Capital Ltd | Financial services | 2020 |