| Progressive UK Recruitment Limited | Administrative & support | 2018 |
| Project and Property Services Limited | Professional & scientific | 2015 |
| Project Fairbreak Ltd | Real estate | 2021 |
| Project Integration Ltd | Information & communication | 2017 |
| Project IQ Training & Consulting Limited | Professional & scientific | 2025 |
| Project Performance Ltd | Health & social care | 2018 |
| Projectability (Professional Services) Limited | Professional & scientific | 2015 |
| Prolung Limited | Health & social care | 2026 |
| Promain Civils Limited | Construction | 2024 |
| Promofy Ltd | Extraterritorial | 2023 |
| Pronet Gaming Ltd | Information & communication | 2008 |
| Propel Law Limited | Administrative & support | 2019 |
| Propella Travel Ltd | Administrative & support | 2019 |
| Propellr Technologies Limited | Construction | 2025 |
| Properly Maintenance Limited | Construction | 2012 |
| Property FX Ltd | Information & communication | 2024 |
| Property Genii Ltd | Real estate | 2017 |
| Property Mine Ltd. | Real estate | 2013 |
| Property Pro Limited | Information & communication | 2023 |
| Propertymc Ltd | Real estate | 2020 |
| Propertyspy Limited | Information & communication | 2000 |
| Propertysurvuk LLP | | 2020 |
| Proplus Property Development Limited | Construction | 2025 |
| Proptech Insights Limited | Professional & scientific | 2025 |
| Prospect Business Centres Limited | Real estate | 2005 |
| Prospect International Ltd | Professional & scientific | 2017 |
| Prospect Partnership Limited | Administrative & support | 2023 |
| Prospect Warner Ltd | Information & communication | 2008 |
| Prosspa Group Ltd | Administrative & support | 2021 |
| Protea Investment Limited | Real estate | 2006 |
| Protech-Solutions Limited | Information & communication | 2008 |
| Protege Consulting Limited | Administrative & support | 2013 |
| Proto Artisan Bakery (Hertford) Limited | Hospitality | 2025 |
| Proto Artisan Bakery (Ware) Limited | Hospitality | 2025 |
| Proto Artisan Bakery Ltd | Hospitality | 2021 |
| Proto Holdings Limited | Financial services | 2025 |
| Proto Property Holdings Limited | Financial services | 2025 |
| Provence Private Hire Limited | Transport & logistics | 1978 |
| Prowling Death Records Limited | Information & communication | 2009 |
| Psalms Care Ltd | Administrative & support | 2022 |
| Psca Consulting Ltd | Professional & scientific | 2015 |
| PSM Sustainability Consulting Limited | Other services | 2024 |
| Psona Group Limited | Administrative & support | 2022 |
| PSP Marine Tapes Limited | Manufacturing | 1990 |
| Psychiatry for ALL Limited | Health & social care | 2022 |
| PT POD Ltd | Health & social care | 2019 |
| Public Perspectives Ltd | Professional & scientific | 2008 |
| Pubpartners Limited | Hospitality | 2025 |
| Puck Coffee Co Ltd | Manufacturing | 2026 |
| Puckpuck Ltd | Wholesale & retail | 2017 |
| Puddy.Net Limited | Information & communication | 2018 |
| PUM DK POD Limited | Information & communication | 2022 |
| Punch UP Media Limited | Information & communication | 2022 |
| Punchard Berkeley Consulting Limited | Professional & scientific | 2020 |
| Punchard Berkeley Limited | Professional & scientific | 2011 |
| Puppets by Post Limited | Extraterritorial | 2002 |
| Puppets Limited | Financial services | 2007 |
| Purcells Utilities Ltd | Construction | 2023 |
| Pure Bricks Limited | Real estate | 2016 |
| Pure Cold Holdings Limited | Manufacturing | 2017 |
| Pure Indoor Golf Club Ltd | Arts & recreation | 2026 |
| Pure Klenz Limited | Manufacturing | 2011 |
| Purewave Ltd | Information & communication | 2003 |
| Purple Basil Limited | Hospitality | 2015 |
| Purple FIN Studios Ltd | Information & communication | 2025 |
| Purple Taxi Service Ltd | Transport & logistics | 2025 |
| Purpose Real Estate Limited | Real estate | 2022 |
| Pursued by a Bear Productions | Arts & recreation | 1999 |
| Putney Spot Ltd | Hospitality | 2022 |
| PVD Invest Ltd | Real estate | 2019 |
| Pyne & Hardy Ltd | Hospitality | 2018 |
| Pyramid Search and Selection Limited | Administrative & support | 2016 |
| Pyxida Limited | Information & communication | 2022 |
| Q Mortgages Limited | Financial services | 2020 |
| Q3 Property Developments Ltd | Real estate | 2021 |
| Qbee Boxing Ltd | Arts & recreation | 2024 |
| QC Investment Management Limited | Real estate | 2017 |
| QCD Vehicle Centre Limited | Wholesale & retail | 2023 |
| Qevlar AI Ltd | Information & communication | 2026 |
| QHJ Limited | Real estate | 2015 |
| Qinnovate Ltd | Information & communication | 2023 |
| QK & Associates Limited | Professional & scientific | 2008 |
| QRS Improve Ltd | Construction | 2021 |
| QU Fitness Ltd | Arts & recreation | 2023 |
| Quadrafon Music Industries Ltd | Information & communication | 2017 |
| Quadrant Spice Limited | Hospitality | 2024 |
| Qualicom Ltd | Professional & scientific | 2023 |
| Qualitaste Limited | Wholesale & retail | 2021 |
| Quality Assure Consultancy Ltd | Education | 2023 |
| Quantmin Limited | Information & communication | 2021 |
| Quantum Training Limited | Education | 2023 |
| Quarterback Services Ltd | Financial services | 2020 |
| Quast Ltd | Professional & scientific | 2015 |
| Queer Connected Limited | Information & communication | 2026 |
| Queertrusted Ltd | Information & communication | 2025 |
| Quentin Brook Associates Limited | Wholesale & retail | 2017 |
| Quentin Brook Ltd | Professional & scientific | 2023 |
| Quest Recruitment Ltd | Administrative & support | 2020 |
| Questionable Bananas Limited | Administrative & support | 2013 |
| Questrow Limited | Real estate | 2021 |