| PGS Freight Consultants Limited | Transport & logistics | 2009 |
| PH Accounting Solutions Limited | Professional & scientific | 2016 |
| PH Sharp Ltd | Professional & scientific | 2015 |
| Phab Weatherbreak Limited | Professional & scientific | 2013 |
| Phab Weatherbreak Properties Limited | Real estate | 2015 |
| Phantech Ltd | Information & communication | 2014 |
| Phantom Signs Limited | Administrative & support | 2015 |
| Phare Care Services Limited | Health & social care | 2023 |
| Pharmacare (London) Limited | Manufacturing | 2009 |
| Pharmalax Limited | Wholesale & retail | 2002 |
| Pharmazz UK Ltd | Wholesale & retail | 2017 |
| Pharmc Ltd | Health & social care | 2019 |
| Phaseone Group Limited | Financial services | 2025 |
| Phaseselect Limited | Professional & scientific | 1991 |
| Phat Tony's Limited | Hospitality | 2022 |
| Phi-Innovate Limited | Information & communication | 2020 |
| Phil Healthcare Services Limited | Health & social care | 2016 |
| Philip & Co Design and Consultancy Ltd | Professional & scientific | 2026 |
| Philip Nolan Accountants (Luton) Limited | Professional & scientific | 2025 |
| Phillpot Tudor-Lewis Limited | Administrative & support | 2018 |
| Phoebe Taylor Beauty Limited | Other services | 2025 |
| Phoenicia Trans Ltd | Transport & logistics | 2025 |
| Phoenix Bird Ltd | Hospitality | 2017 |
| Phoenix Construction (Beds) Ltd | Administrative & support | 2018 |
| Phoenix Document Solutions Limited | Administrative & support | 2017 |
| Phoenix Occupational Therapy for Children Limited | Health & social care | 2015 |
| Phoenix PCN Luton Ltd | Health & social care | 2024 |
| Phoenix Property CP Limited | Real estate | 2024 |
| Phoenix Solutions 247 Ltd | Wholesale & retail | 2018 |
| Phoenix Teaching and Education Ltd | Education | 2024 |
| Phoenix Youth Empowerment CIC | Health & social care | 2023 |
| Phoenixworks Media Group Ltd | Information & communication | 2024 |
| Phone Centre (UK) Limited | Wholesale & retail | 2016 |
| Phone Point Limited | Wholesale & retail | 2018 |
| PHONES2GADGETS Limited | Wholesale & retail | 2024 |
| PHONES4CASH Ltd | Wholesale & retail | 2026 |
| Phoniac Limited | Information & communication | 2024 |
| Phos Live Ltd | Arts & recreation | 2024 |
| Photex Design Limited | Professional & scientific | 2015 |
| Phoxom Properties Limited | Real estate | 2014 |
| Phronesis Learning Group Ltd | Education | 2026 |
| Physicaled+ Limited | Education | 2024 |
| Physio Finder Limited | Health & social care | 2025 |
| Physioheal Physiotherapy Clinic Limited | Health & social care | 2011 |
| PI Carbon Composites Ltd | Manufacturing | 2021 |
| PI R2 Development Ltd | Construction | 2013 |
| Piacare Limited | Financial services | 2019 |
| Piaro Ltd | Information & communication | 2024 |
| PIC Trans Ltd | Transport & logistics | 2018 |
| Picasso Hair Stylist Limited | Other services | 2011 |
| Pick N Save Limited | Information & communication | 2025 |
| Picknship Logistics Limited | Transport & logistics | 2025 |
| Pictees Ltd | Manufacturing | 2024 |
| Picton & Sons Limited | Construction | 1982 |
| Pieroth Limited | Wholesale & retail | 1961 |
| Pierpoint Consultancy Ltd | Professional & scientific | 2025 |
| Pietka Ltd | Real estate | 2025 |
| Pigeon Building Ltd | Construction | 2016 |
| Pigeonbox Ltd | Wholesale & retail | 2021 |
| Pike's Property Limited | Administrative & support | 2020 |
| Pilates at Home Ltd | Health & social care | 2020 |
| Pilgrims AI Ltd | Real estate | 2023 |
| Pillclub Limited | Wholesale & retail | 2022 |
| Pillow Talk Media Ltd | Professional & scientific | 2025 |
| Pilot Light Heating Ltd | Construction | 2017 |
| Pimlico Commercial Catering Repairs Ltd | Manufacturing | 2023 |
| Pimliko Consultants Limited | Construction | 2009 |
| Pimliko Supplies Limited | Wholesale & retail | 2009 |
| PIN Wise Ltd | Construction | 2022 |
| Pinc Group Limited | Real estate | 2024 |
| Pincess Lodge RTM Company Ltd | Households | 2018 |
| Pinel Consulting Limited | Professional & scientific | 2014 |
| Pinewood Classic Motor Cars Ltd | Wholesale & retail | 2015 |
| Pinewood Property Developments Limited | Construction | 2004 |
| Pinewood Property Holdings Limited | Financial services | 2025 |
| Pingmi Ltd | Information & communication | 2025 |
| Pink Eatery Limited | Hospitality | 2021 |
| Pink Financing Limited | Wholesale & retail | 2019 |
| Pinkelz Creative Realm CIC | Administrative & support | 2025 |
| Pinkelz Fashion Ltd | Wholesale & retail | 2020 |
| Pinnacle Estates Management Ltd | Real estate | 2019 |
| Pinnacle Group Investments Ltd | Real estate | 2024 |
| Pinnacle Horizons Living Limited | Health & social care | 2026 |
| Pinnacle Point Solutions Ltd | Other services | 2024 |
| Pinnacle Property Maintenance Ltd | Other services | 2023 |
| Pinnacle Tuition Ltd | Education | 2020 |
| Pinpoint Estates Luton Limited | Real estate | 2023 |
| Pintescu Services Ltd | Construction | 2013 |
| Pioneer Learning Trust | Education | 2012 |
| Pioneer Packaging Limited | Manufacturing | 2020 |
| Pioneer Plasterers Ltd | Construction | 2015 |
| Pioneer Property Ltd | Real estate | 2018 |
| Pioneer Traffic Management Ltd | Professional & scientific | 2018 |
| Pipeline Specialists Supply Limited | Construction | 2025 |
| Pipes Heating & Plumbing Ltd | Construction | 2012 |
| Pippys Fine Foods Ltd | Wholesale & retail | 2026 |
| PIS Services Limited | Transport & logistics | 2023 |
| Pisko's Kitchens & Bedrooms Limited | Construction | 2021 |
| Pislariu & Sons Ltd | Construction | 2016 |
| Pitbull Racing Limited | Other services | 2004 |