| OT Services Property Ltd | Construction | 2023 |
| Otra Group Limited | Hospitality | 2022 |
| Outsource Agency Ltd | Administrative & support | 2023 |
| Outthere RPO Ltd | Administrative & support | 2012 |
| Overtam Ltd | Hospitality | 2015 |
| Owen Oliver Associates Ltd | Information & communication | 2024 |
| OWL Motor Services Ltd | Wholesale & retail | 2006 |
| Ownground Property Management Limited | Households | 1993 |
| OX Marketing Ltd | Manufacturing | 2019 |
| P & Y Ltd | Professional & scientific | 2022 |
| P H Brickwork Ltd | Construction | 2007 |
| P J Estates Limited | Hospitality | 2007 |
| P Knight Properties Limited | Real estate | 2012 |
| P.M GAS Heating & Plumbing Limited | Construction | 2018 |
| P3 Developments Ltd | Construction | 2021 |
| P3NROSE Ltd | Professional & scientific | 2025 |
| Pacdan Management Limited | Financial services | 2011 |
| Pace Logistics Ltd | Transport & logistics | 2026 |
| Paint Chill Co Ltd | Wholesale & retail | 2018 |
| Palette & Plaster Limited | Construction | 2025 |
| Pallet Project Limited | Manufacturing | 2018 |
| Palm Court Freehold Limited | Households | 2022 |
| Palmer Flooring Contractors Ltd | Construction | 2025 |
| Pamodzi Creatives CIC | Arts & recreation | 2018 |
| Panache Executive Cars Limited | Transport & logistics | 2020 |
| Parade Apartments RTM Company Limited | Hospitality | 2009 |
| Parade Tearooms Gunwharf Ltd | Hospitality | 2018 |
| Parade Tearooms Ltd | Hospitality | 2015 |
| Paratha and Chai Ltd | Hospitality | 2020 |
| Parg Ltd | Hospitality | 2024 |
| Park Building Solutions Limited | Construction | 2024 |
| Park Court (Portsmouth) Residents Association Limited | Hospitality | 1985 |
| Park House Freehold (Southsea) Limited | Households | 2006 |
| Parkers Pets Cosham Limited | Wholesale & retail | 2019 |
| Parkers Pets Limited | Wholesale & retail | 2018 |
| Parqtech Ltd | Other services | 2025 |
| Part Worn Tyres 4 U Limited | Wholesale & retail | 2014 |
| Parwa K1 Ltd | Other services | 2024 |
| Path Education Services Ltd | Education | 2023 |
| Paul Moreton Building Services Ltd | Construction | 2025 |
| Paul Murray Investments Limited | Financial services | 2009 |
| Pawfix Natural Ltd | Wholesale & retail | 2024 |
| Paws Pet Services Limited | Other services | 2025 |
| Paytec Online Payroll Services Limited | Other services | 2005 |
| Pbjo, Co Ltd | Administrative & support | 2017 |
| PBS Plumbing & Building Ltd | Construction | 2025 |
| PCS Airtech Ltd | Construction | 2025 |
| PDL Therapies Limited | Health & social care | 2026 |
| Peak Performance Sports Limited | Arts & recreation | 2010 |
| Pebble Payroll Limited | Administrative & support | 2021 |
| Pedal Potential C.I.C. | Arts & recreation | 2014 |
| Peekaboolittles Ltd | Professional & scientific | 2026 |
| Pegasys Retail Solutions Ltd. | Information & communication | 2014 |
| Peggy's Wheels Limited | Transport & logistics | 2025 |
| Pendragon Apartments RTM Ltd | Households | 2009 |
| Pengfei Ltd | Hospitality | 2026 |
| Pennymaison Ltd | Other services | 2024 |
| People and Paperwork Ltd | Public administration | 2025 |
| Percy Harrison (Opticians) Limited | Health & social care | 1960 |
| Perennial Fireproofing Ltd | Public administration | 2020 |
| Perfect Pitch Productions Limited | Information & communication | 2000 |
| Perfection for Choice Ltd | Construction | 2016 |
| Perfection for Choice Restoration Ltd | Construction | 2021 |
| Performance Management Global Ltd | Professional & scientific | 2024 |
| Periculum Consulting Ltd | Administrative & support | 2025 |
| Perryman Engineering Ltd | Professional & scientific | 2014 |
| Perseus Hospitality Limited | Hospitality | 2024 |
| Personal Trainer Southsea Ltd | Arts & recreation | 2020 |
| Perth House (Portsmouth) Management Company Limited | Professional & scientific | 1982 |
| Pete Codling Artist Ltd | Arts & recreation | 2020 |
| PFC Southern Ltd | Construction | 2018 |
| Pharma Marketing Consulting Ltd | Professional & scientific | 2024 |
| Pharmafed Ltd | Wholesale & retail | 2021 |
| Phil Rose Design Ltd | Professional & scientific | 2023 |
| Phillips Auto Electrical Limited | Extraterritorial | 2018 |
| Phishing Forensics Ltd | Information & communication | 2017 |
| Phiyindhara Limited | Other services | 2025 |
| Phoenix MOT Centre Ltd | Wholesale & retail | 2025 |
| Phoenix Rise Retreats Limited | Real estate | 2024 |
| Phoenix Sealant Specialist Ltd | Construction | 2025 |
| Phone Protect Ltd | Wholesale & retail | 2010 |
| Phone Studio South Limited | Wholesale & retail | 2025 |
| Photon Renewables Limited | Construction | 2023 |
| PIA Brickwork Solutions Ltd | Construction | 2025 |
| Pick UP Collect and Go Ltd | Transport & logistics | 2025 |
| Picms Ltd | Information & communication | 2026 |
| Pier Beach Ltd | Hospitality | 2021 |
| Pigeon Books Ltd | Wholesale & retail | 2022 |
| Pinecross Timber Supplies Limited | Wholesale & retail | 2026 |
| Pingzonegroup Limited | Other services | 2020 |
| Pink Croft Limited | Real estate | 2020 |
| Pink Development Ltd | Construction | 2018 |
| Pink Rock Limited | Financial services | 2020 |
| Piotr Sekowski Ltd | Professional & scientific | 2020 |
| Pixzarloop Ltd | Professional & scientific | 2021 |
| PJ Hambrook Limited | Hospitality | 2012 |
| PJ Harbourside Limited | Hospitality | 2008 |
| PJ Holdings (UK) Limited | Financial services | 2008 |
| PJ Holiday Homes Limited | Other services | 2023 |
| PJ Property Investment Limited | Real estate | 2012 |