| Portsmouth City Football Club (Fratton Park) Limited | Arts & recreation | 2019 |
| Portsmouth City Football Club Limited | Arts & recreation | 2020 |
| Portsmouth Coffee Limited | Hospitality | 2014 |
| Portsmouth Commercial Services Limited | Transport & logistics | 2013 |
| Portsmouth Community Football Club Limited | Arts & recreation | 2012 |
| Portsmouth Creates CIC | Education | 2019 |
| Portsmouth Cultural Education Partnership C.I.C. | Education | 2024 |
| Portsmouth Demolition & Salvage Limited | Construction | 2009 |
| Portsmouth Diamond Drilling Ltd | Construction | 2006 |
| Portsmouth Diocesan Board of Finance(The) | Other services | 1927 |
| Portsmouth Diocesan Council for Social Responsibility | Other services | 2011 |
| Portsmouth Elder Care Limited | Health & social care | 2018 |
| Portsmouth Electrical Ltd | Construction | 2012 |
| Portsmouth F C Limited | Arts & recreation | 2018 |
| Portsmouth Fibreglass Limited | Manufacturing | 2013 |
| Portsmouth Fire Compliance Ltd | Construction | 2023 |
| Portsmouth Food Ltd | Hospitality | 2025 |
| Portsmouth Football Club Limited | Arts & recreation | 2018 |
| Portsmouth Football Club(Fratton Park) Limited | Arts & recreation | 2020 |
| Portsmouth Forest School CIC | Education | 2021 |
| Portsmouth Fresh Fruit and VEG Limited | Wholesale & retail | 2025 |
| Portsmouth Fruit and Flower Ltd | Wholesale & retail | 2001 |
| Portsmouth Furniture Centre Ltd | Wholesale & retail | 2015 |
| Portsmouth Garden Help Ltd | Administrative & support | 2020 |
| Portsmouth GAS Heating Limited | Construction | 2021 |
| Portsmouth GAS Ltd | Administrative & support | 2017 |
| Portsmouth Harbour Agents Ltd | Administrative & support | 2016 |
| Portsmouth Harbour Renaissance Limited | Real estate | 1996 |
| Portsmouth Historic Dockyard Operations Limited | Arts & recreation | 2020 |
| Portsmouth Historic Quarter Trust | Arts & recreation | 1985 |
| Portsmouth Hospitality Ltd | Hospitality | 2026 |
| Portsmouth International Fish Bazar Limited | Wholesale & retail | 2024 |
| Portsmouth International Food Centre Limited | Wholesale & retail | 2015 |
| Portsmouth Joinery Products Limited | Construction | 2006 |
| Portsmouth Kebab Ltd | Hospitality | 2023 |
| Portsmouth Knee Clinic Ltd | Health & social care | 2012 |
| Portsmouth Maemes Ltd | Hospitality | 2022 |
| Portsmouth Marine Services Ltd | Manufacturing | 2020 |
| Portsmouth Mediation Service | Health & social care | 1996 |
| Portsmouth Mini Skips Ltd | Water & waste | 2023 |
| Portsmouth MOT Centre Limited | Wholesale & retail | 2021 |
| Portsmouth Muslim Academy | Education | 2007 |
| Portsmouth Nail Bar Ltd | Other services | 2024 |
| Portsmouth Naval Base Property (Priddy's Hard) Limited | Arts & recreation | 2009 |
| Portsmouth Naval Base Property Company (Queen Street) Limited | Real estate | 2003 |
| Portsmouth Naval Base Property Company Limited | Real estate | 2001 |
| Portsmouth Naval Base Trading Co. Limited | Wholesale & retail | 2013 |
| Portsmouth Northsea Swim Trust Ltd | Arts & recreation | 1997 |
| Portsmouth Padel Ltd | Education | 2025 |
| Portsmouth Party Rooms Limited | Other services | 2012 |
| Portsmouth Paving and Roofing Limited | Construction | 2025 |
| Portsmouth Phoenix Community Interest Company | Education | 2025 |
| Portsmouth Pizza Ltd | Hospitality | 2024 |
| Portsmouth Plastering Services Ltd | Construction | 2019 |
| Portsmouth Primary Care Alliance Limited | Health & social care | 2015 |
| Portsmouth Property Care Limited | Hospitality | 2025 |
| Portsmouth Quay Freehold Company Limited | Households | 2018 |
| Portsmouth Quay Management Company Limited | Households | 2002 |
| Portsmouth Raffle Car Ltd | Arts & recreation | 2025 |
| Portsmouth Railex Ltd | Administrative & support | 2026 |
| Portsmouth Rangers Football Club Limited | Arts & recreation | 2014 |
| Portsmouth Rental Limited | Real estate | 2021 |
| Portsmouth Roller Wenches Limited | Arts & recreation | 2016 |
| Portsmouth Royal Dockyard Historical Trust | Arts & recreation | 1994 |
| Portsmouth Royal Maritime Club Limited | Hospitality | 1998 |
| Portsmouth School of Gymnastics | Arts & recreation | 1996 |
| Portsmouth Shockwave Ltd | Health & social care | 2025 |
| Portsmouth Sports Injury Clinic Limited | Health & social care | 2006 |
| Portsmouth Students' Union Trading Company Limited | Administrative & support | 2007 |
| Portsmouth Studios Limited | Hospitality | 2015 |
| Portsmouth Tennis Academy Ltd | Arts & recreation | 2013 |
| Portsmouth Tortoise Rescue Limited | Agriculture & fishing | 2021 |
| Portsmouth Transport Services Limited | Wholesale & retail | 2022 |
| Portsmouth Travels Ltd | Administrative & support | 2020 |
| Portsmouth United F.C Limited | Arts & recreation | 2014 |
| Portsmouth Vets Ltd | Professional & scientific | 2024 |
| Portsmouth Women Alliance CIC | Education | 2026 |
| Portsmouth Women's Community Football Club Limited | Arts & recreation | 2023 |
| Portus Property Limited | Real estate | 2025 |
| Porucznik Kabura Ltd | Transport & logistics | 2016 |
| Positive Change Consulting Limited | Professional & scientific | 2025 |
| Positive Juice Ltd | Hospitality | 2020 |
| Positivenergy Limited | Professional & scientific | 2013 |
| Postcode Publications Limited | Information & communication | 2011 |
| Potter UK Holdings Limited | Professional & scientific | 2008 |
| Pottery PIG & Print Ltd | Arts & recreation | 2026 |
| Powell Creative Limited | Professional & scientific | 2010 |
| Power Clean UK Group Ltd | Administrative & support | 2021 |
| Power Discount LLP | | 2011 |
| Power GEN Careers Ltd | Other services | 2010 |
| Powered by HC Ltd. | Financial services | 2024 |
| Powerhost Limited | Information & communication | 2019 |
| Powerscourt Motors Ltd | Wholesale & retail | 2013 |
| Powertex UK Limited | Wholesale & retail | 2014 |
| PPH South Ltd | Construction | 2015 |
| PPT (UK) Holdings Limited | Real estate | 2002 |
| Prahran Freight Management Ltd | Transport & logistics | 2024 |
| Praveenth Kanagaraj Limited | Administrative & support | 2019 |
| Prcst Ltd | Information & communication | 2022 |
| Precipice Management Ltd | Construction | 2018 |