| PNT Healthcare Services Ltd | Health & social care | 2019 |
| Pocket Profit Limited | Administrative & support | 2026 |
| Pocketstylist Ltd | Wholesale & retail | 2019 |
| Podsantrans Sport UK Ltd | Transport & logistics | 2020 |
| Pohwer | Other services | 1997 |
| Polakkattil Ltd | Hospitality | 2025 |
| Poles Park Residents Limited | Households | 1992 |
| Polestar Services Limited | Hospitality | 2017 |
| Polished Stone Limited | Wholesale & retail | 2003 |
| Politropon Properties Ltd | Real estate | 2024 |
| Polkadot Ideas Limited | Administrative & support | 2018 |
| Pollan Investments | Financial services | 2018 |
| Pollen Labs Studio IP Ltd | Financial services | 2024 |
| Pollinate Studio Ltd | Administrative & support | 2024 |
| Pomroy Associates Limited | Professional & scientific | 2016 |
| POP Foundation CIC | Health & social care | 2024 |
| Pop-Up Toilet Company UK Ltd | Construction | 2017 |
| Poppingo Limited | Manufacturing | 2021 |
| Poppy's Animal Services Ltd | Agriculture & fishing | 2025 |
| Popup United Ltd | Administrative & support | 2018 |
| Poroger Holdings Limited | Administrative & support | 2017 |
| Porter Pepperell Ltd | Wholesale & retail | 2019 |
| Portfolio Group Ltd | Hospitality | 2016 |
| Portfolio Serviced Accommodation Ltd | Real estate | 2015 |
| Portland Developments Limited | Real estate | 1983 |
| Ports Plus Limited | Transport & logistics | 2025 |
| Positive Expressions Ltd | Education | 2021 |
| Postcode Radio Limited | Hospitality | 2016 |
| Posterity Property Ltd | Real estate | 2021 |
| Potato Asteroid Limited | Information & communication | 2018 |
| Potton Road Properties Limited | Real estate | 2014 |
| Pound Avenue Management (Stevenage) Limited | Households | 1993 |
| Power Cuisine Ltd | Construction | 2025 |
| Power Fencing Services Ltd | Administrative & support | 2019 |
| Powered by Naughty Paws Ltd | Wholesale & retail | 2024 |
| Powerlines Creative Ltd | Professional & scientific | 2025 |
| PPA Group Limited | Administrative & support | 2015 |
| Ppol Ltd | Professional & scientific | 2017 |
| PR Electrical Installation Services Limited | Construction | 2024 |
| PR1ME Electrical Limited | Construction | 2012 |
| Precise Holdings Ltd | Information & communication | 2021 |
| Precision Radiology Reports Ltd | Health & social care | 2024 |
| Precision Roofing and Building Maintenance Ltd | Construction | 2018 |
| Preeya Properties Limited | Real estate | 2008 |
| Preeya Property Lettings Agency Limited | Construction | 2003 |
| Pregis Limited | Manufacturing | 2016 |
| Premier BBC Group Ltd | Construction | 2023 |
| Premier Carpet Cleaning ST Ltd | Administrative & support | 2023 |
| Premier Carpets & Flooring (Hitchin) Ltd | Wholesale & retail | 2025 |
| Premier Developments (Hitchin) Limited | Real estate | 2003 |
| Premier GAS Services Ltd | Construction | 2025 |
| Premier Joinery Solutions Holdings Limited | Manufacturing | 2024 |
| Premier Solutions (UK) Limited | Professional & scientific | 2010 |
| Premium Artificial Grass Limited | Administrative & support | 2014 |
| Premium Hair Gallery Limited | Other services | 2025 |
| Premkar Ltd | Hospitality | 2022 |
| Presentation People Ltd | Manufacturing | 2018 |
| Press Cartel Ltd | Professional & scientific | 2018 |
| Prestige Building&Surfacing Ltd | Construction | 2026 |
| Prestige Motors (Herts) Limited | Wholesale & retail | 2013 |
| Prestige Schools Ltd | Education | 2023 |
| Prestige Taxi Rentals Ltd | Transport & logistics | 2023 |
| Prestige Travels Stevenage Ltd | Transport & logistics | 2022 |
| Prestigio Transport Ltd | Transport & logistics | 2023 |
| Pretty Good Pictures Limited | Information & communication | 2017 |
| Prevail Sports & Entertainment Group Ltd | Arts & recreation | 2023 |
| Prevalent Property Limited | Real estate | 2020 |
| PRG Door Systems Limited | Manufacturing | 2014 |
| Pride Cleaners Ltd | Administrative & support | 2020 |
| Priestley Consulting Services Limited | Administrative & support | 2016 |
| Prima Flooring Limited | Construction | 2014 |
| Primary Broadband Limited | Information & communication | 2020 |
| Primary Care Medical Chambers Ltd | Administrative & support | 2018 |
| Primary IT Support Limited | Information & communication | 2003 |
| Prime 144022 Investments Ltd | Financial services | 2022 |
| Prime Choice Healthcare Ltd | Health & social care | 2023 |
| Prime Circle Capital Ltd | Financial services | 2025 |
| Prime Heating and Plumbing Ltd | Construction | 2014 |
| Prime Marque Services Limited | Administrative & support | 2019 |
| Prime Partnership & Training Ltd | Public administration | 2021 |
| Prime Residential Management Ltd | Real estate | 2007 |
| Primeheart Limited | Health & social care | 2025 |
| Primenet Limited | Information & communication | 1995 |
| Primepoint Trading Ltd | Wholesale & retail | 2025 |
| Primewatch Security Solutions Ltd | Administrative & support | 2025 |
| Primis Installations Limited | Professional & scientific | 2020 |
| Principal Controls Ltd | Construction | 2024 |
| PRINCIPAL8 Ltd | Professional & scientific | 2019 |
| Print Stitch UK Limited | Extraterritorial | 2016 |
| Printcheck Ltd | Professional & scientific | 2018 |
| Printzymes Ltd | Information & communication | 2020 |
| Prio Ltd | Wholesale & retail | 2024 |
| Priority Planning Ltd | Extraterritorial | 2013 |
| Priority Plus Care Ltd | Health & social care | 2010 |
| Priority TM Ltd | Administrative & support | 2003 |
| Priority Traffic Management Ltd | Financial services | 2016 |
| Priory Childcare Ltd | Education | 2009 |
| Priory Court(Hitchin)Limited | Households | 1965 |
| Pristine Essence Solutions Limited | Wholesale & retail | 2024 |
| Pristine Sneakers Ltd | Other services | 2025 |