| Porvoon Paahtimo Oy | Hospitality | 2001 |
| Porvoon Paalupiste Oy | Wholesale & retail | 2000 |
| Porvoon Panimo Oy | Hospitality | 2010 |
| Porvoon Parkfood Oy | Other services | 1996 |
| Porvoon Parkki Oy | Transport & logistics | 1997 |
| Porvoon Pienet Palvelukset Oy | Manufacturing | 2019 |
| Porvoon Pihapojat avoin yhtiö | Administrative & support | 2024 |
| Porvoon Puutyö Oy | Manufacturing | 2010 |
| Porvoon RELAX Oy | Hospitality | 1988 |
| Porvoon Rakennuskonevuokraamo Oy | Administrative & support | 1999 |
| Porvoon Rakennuskonsultit Oy | Professional & scientific | 2024 |
| Porvoon Rakennuspalvelu Oy | Construction | 2003 |
| Porvoon Rantakioski & Venepalvelu Ky | Wholesale & retail | 1983 |
| Porvoon Ratsutalli Oy Borgå Ridstall Ab | Education | 2014 |
| Porvoon Realisointipörssi Oy | Wholesale & retail | 1992 |
| Porvoon Rengaspalvelu Oy Borgå Däckservice Ab | Wholesale & retail | 2008 |
| Porvoon Retkeilymaja kommandiittiyhtiö | Hospitality | 1989 |
| Porvoon Saariston Hoitokunta Oy | Water & waste | 2003 |
| Porvoon Smash Burgeri Oy | Hospitality | 2026 |
| Porvoon Sähkötyö Oy | Construction | 1997 |
| Porvoon TM Rakennus Oy | Construction | 2021 |
| Porvoon Talonmiespalvelu Ky | Health & social care | 2008 |
| Porvoon Talotekniikka Oy | Construction | 2023 |
| Porvoon Tanssistudio Oy | Education | 1985 |
| Porvoon Tapetti ja Väri Oy | Wholesale & retail | 2025 |
| Porvoon Teollisuussähkö Oy | Construction | 1996 |
| Porvoon Tilipalvelu Oy | Professional & scientific | 1986 |
| Porvoon Vaihtokaluste Oy | Wholesale & retail | 2006 |
| Porvoon Valojäljennös Oy | Administrative & support | 1993 |
| Porvoon Vanha Ikkuna Oy | Construction | 2021 |
| Porvoon Varasto Oy | Real estate | 1974 |
| Porvoon Viemäripalvelu Oy | Water & waste | 2006 |
| Porvoon Vn Rakennus Oy | Administrative & support | 2018 |
| Porvoon Vuokravälitys Oy | Real estate | 1995 |
| Porvoon Ykkösrakennus Oy | Construction | 2020 |
| Porvoon Yrityskiinteistöt Oy | Real estate | 1998 |
| Porvoon Yrityslaskenta Oy | Professional & scientific | 1985 |
| Porvoon Yritystalo Oy | Real estate | 1975 |
| Porvoon julkisivupalvelut oy | Construction | 2015 |
| Porvoon pyöräkeskus Oy Borgå cykelcenter Ab | Wholesale & retail | 2006 |
| Porvoon tenniskoulu Oy | Education | 2024 |
| Porvoon viemäriavaus Oy | Water & waste | 2014 |
| Porvoonjoen Helmi Oy | Hospitality | 2021 |
| Posintra Oy | Professional & scientific | 1999 |
| Poulsen Invest Oy | Professional & scientific | 2021 |
| Poveko Oy | Manufacturing | 2023 |
| PowerBank Ventures Oy | Professional & scientific | 2007 |
| Preiskari Group Oy | Professional & scientific | 2023 |
| Premia Travel Oy | Administrative & support | 1998 |
| Pretrealize Oy | Professional & scientific | 2022 |
| Primar Oy | Education | 2005 |
| PrimeR Oy | Professional & scientific | 2014 |
| Primoberg Oy | Transport & logistics | 2024 |
| PriraNova Oy | Construction | 2014 |
| Pro Effective Oy | Administrative & support | 2021 |
| Pro Image Oy | Professional & scientific | 1990 |
| Pro Pesu Oy | Other services | 2010 |
| Pro Päätös Oy | Professional & scientific | 2020 |
| Pro Synthesis Oy | Professional & scientific | 2012 |
| Pro-Insight Finland Oy | Professional & scientific | 2020 |
| Pro-Machine Finland Oy | Manufacturing | 2001 |
| ProApp Oy | Information & communication | 2022 |
| ProCult Productions Ab | Arts & recreation | 2012 |
| Prohab Oy | Construction | 1999 |
| Projektipalvelu Hyvönen Oy | Professional & scientific | 2012 |
| Projektitoimia Oy | Professional & scientific | 2024 |
| Promans Rakennus OY | Administrative & support | 2023 |
| Promosport Oy | Professional & scientific | 1992 |
| Prop Projects Oy | Real estate | 2020 |
| Proport-Trading Oy | Wholesale & retail | 1989 |
| ProtoRhino Oy | Professional & scientific | 2009 |
| Prowess Education Oy | Education | 2026 |
| Psykoterapia MiiL Oy | Health & social care | 2023 |
| Psykoterapia Minna Kangasmaa Oy | Health & social care | 2019 |
| PtvHold Oy | Professional & scientific | 2022 |
| Ptvgym Oy | Arts & recreation | 2016 |
| Ptvgym Partners Oy | Arts & recreation | 2023 |
| Ptvlabs Oy | Arts & recreation | 2023 |
| Ptvmuscle Oy | Arts & recreation | 2023 |
| Puhtix Oy | Administrative & support | 2024 |
| Pulkkinen Kylmäpalvelu Oy | Manufacturing | 2021 |
| Punnushuone Oy | Arts & recreation | 2016 |
| Purmel Hospitality Oy | Professional & scientific | 2013 |
| Putkityökalu Oy Hepac tools Finland | Wholesale & retail | 1995 |
| Putterin Helmi Oy | Real estate | 2000 |
| Puuprojekti Ky M. Virtanen | Manufacturing | 1991 |
| Puusepänliike Haapatalo Oy | Real estate | 1987 |
| Puutyö Wiima Oy | Manufacturing | 2021 |
| Pyhtään Kuituverkko Oy | Information & communication | 2019 |
| Pyhäjärven Lomakylä Oy | Hospitality | 2010 |
| Pykälistön Urheiluhevoset Ky | Arts & recreation | 1995 |
| Pylkkö Group Oy | Health & social care | 2011 |
| Pyntve Oy | Professional & scientific | 1976 |
| PyykkiKoira Oy | Other services | 2025 |
| Pyykkö Group oy | Construction | 2025 |
| Pyyn pidot Oy | Hospitality | 2022 |
| Pyörä ja Urheilu Kannos Oy | Real estate | 1935 |
| Pääbusiness Oy | Financial services | 1987 |
| Pääskykodit Oy | Construction | 2026 |
| Qatalisgroup Oy | Administrative & support | 2000 |