| Petri Pölkki Oy | Construction | 2014 |
| Petri Tamminen Oy | Professional & scientific | 1992 |
| Petri's Oy | Wholesale & retail | 2007 |
| Petrus Catering Oy | Real estate | 2016 |
| Petter Larsen Holding Oy | Administrative & support | 2014 |
| Pham HM Oy | Other services | 2026 |
| Phiit Virtual Trading Oy | Information & communication | 2025 |
| Phiphens Oy | Professional & scientific | 2024 |
| Pianokeisarit Oy | Transport & logistics | 2021 |
| Picote Oy Ltd | Construction | 1993 |
| Picote Solutions Oy Ltd | Manufacturing | 2017 |
| Piece 'n' Love Oy | Hospitality | 2015 |
| Pieni Suklaatehdas Porvoo Oy - Lilla Chokladfabriken Borgå Ab | Manufacturing | 2016 |
| Piha-Center Mustonen Oy | Wholesale & retail | 1977 |
| Pihlajarinteen Majoitus oy | Hospitality | 2011 |
| Pii Tili Oy | Professional & scientific | 2024 |
| Piispa Sales Excellence Oy | Professional & scientific | 2025 |
| Pillarion Oy | Real estate | 2024 |
| Pilot Team Oy | Transport & logistics | 2024 |
| Pine Island Consulting Oy | Professional & scientific | 2023 |
| PintaFlow Oy | Construction | 2025 |
| Piokkio Oy | Professional & scientific | 2024 |
| Pip-Tuote Oy | Construction | 1996 |
| Piper Music Oy | Arts & recreation | 2025 |
| Pizzahour oy | Hospitality | 2024 |
| Pizzakungen Oy | Hospitality | 2016 |
| Plamacon Oy | Construction | 2022 |
| Plastoco Oy Ab | Manufacturing | 1980 |
| Playground Productions Oy Ab | Information & communication | 1996 |
| Plus Katsastus Porvoo Oy | Professional & scientific | 2015 |
| PoCompany Oy | Professional & scientific | 2020 |
| Pocatello Oy | Real estate | 1993 |
| Pohjois-Helsingin Sijoitus Oy | Financial services | 1988 |
| Pokela Consulting Oy | Professional & scientific | 2010 |
| Pokhara group oy | Hospitality | 2023 |
| Polar Finnica Oy | Wholesale & retail | 2022 |
| Polares Oy | Information & communication | 2023 |
| Pomoton Oy | Professional & scientific | 2008 |
| Poomu Oy | Professional & scientific | 2020 |
| PopUnion Oy | Information & communication | 2012 |
| Porin Antiikki ja Taide kommandiittiyhtiö | Wholesale & retail | 1993 |
| Porvoo Bygg & Design Oy | Construction | 2024 |
| Porvoo Event Factory Oy Ab | Real estate | 2011 |
| Porvoo Foods Oy | Hospitality | 2016 |
| Porvoo Freetime Store OY | Wholesale & retail | 2014 |
| Porvoo Housing Oy | Real estate | 2003 |
| Porvoo Ski Oy | Arts & recreation | 2025 |
| Porvoo TSF Oy | Hospitality | 2023 |
| Porvoo Tours Oy | Administrative & support | 2008 |
| Porvoon Aleksanterinkadun hammaslääkärit Oy | Health & social care | 2018 |
| Porvoon Aputyö ja Urakointi Oy | Administrative & support | 1993 |
| Porvoon Ararat avoin yhtiö | Hospitality | 2016 |
| Porvoon Autofix Oy | Other services | 2018 |
| Porvoon Autokiilto Oy | Wholesale & retail | 1978 |
| Porvoon Autopiste Oy | Other services | 2016 |
| Porvoon Autoservice Oy | Other services | 2022 |
| Porvoon Autotech Oy Ab | Other services | 2010 |
| Porvoon Autovaruste Oy | Wholesale & retail | 1990 |
| Porvoon Dentogen Oy | Health & social care | 1991 |
| Porvoon Ekokauppa Oy | Wholesale & retail | 2011 |
| Porvoon Eläinlääkäriasema Oy | Professional & scientific | 1984 |
| Porvoon Eläintuhkaus PET Oy | Other services | 2019 |
| Porvoon Fysioterapia Ky | Health & social care | 1996 |
| Porvoon Habita Oy | Real estate | 1999 |
| Porvoon Hammaslääkärit Oy | Health & social care | 2014 |
| Porvoon Huoltomiehet Oy | Administrative & support | 2023 |
| Porvoon Jokirannan Yrityspuisto Oy | Real estate | 2013 |
| Porvoon Kauneudenhoitola DayDream Ky | Other services | 2009 |
| Porvoon Kehokunto Oy | Health & social care | 1989 |
| Porvoon Kello Hannes ja Helvi Heikkilä | Wholesale & retail | 1949 |
| Porvoon Keräyspaperi Ky | Water & waste | 1990 |
| Porvoon Kiinteistöpalvelu Oy | Administrative & support | 2026 |
| Porvoon Kiinteistöpojat Oy | Real estate | 1989 |
| Porvoon Kirjakeskus Oy | Transport & logistics | 2011 |
| Porvoon Kivi & Viherasennus Oy | Manufacturing | 2020 |
| Porvoon Kodintekniikka Oy | Wholesale & retail | 2008 |
| Porvoon Kodit Oy Borgå Hem Ab | Real estate | 1966 |
| Porvoon Konehuolto Oy | Other services | 1977 |
| Porvoon Kukkapalvelu Ky | Wholesale & retail | 2002 |
| Porvoon Kukkatalo Oy | Wholesale & retail | 2018 |
| Porvoon Kuntoutuspiste Oy | Health & social care | 2024 |
| Porvoon Kutteri Oy | Transport & logistics | 2022 |
| Porvoon Kylmäpalvelu Oy | Construction | 2011 |
| Porvoon Kymppiputki Oy | Construction | 2004 |
| Porvoon LVI-Group Oy | Construction | 2016 |
| Porvoon LVI-Palvelu Oy | Construction | 2015 |
| Porvoon LVI-talo Oy | Construction | 2006 |
| Porvoon Laatuauto Tuominen Oy | Wholesale & retail | 2018 |
| Porvoon Laatupellitys Oy | Construction | 2019 |
| Porvoon Laituri Oy | Hospitality | 2007 |
| Porvoon Lemmikkilääkärit Oy | Professional & scientific | 2012 |
| Porvoon Lukkohuolto Oy | Wholesale & retail | 1972 |
| Porvoon Lukkosepät Oy | Wholesale & retail | 2017 |
| Porvoon Metallirakenne Oy | Manufacturing | 2014 |
| Porvoon Mikrokulma Oy | Wholesale & retail | 1988 |
| Porvoon Mittaletku Oy | Wholesale & retail | 2006 |
| Porvoon Muoti-Aitta Oy | Wholesale & retail | 1983 |
| Porvoon Nappi ja Lanka Oy | Wholesale & retail | 1995 |
| Porvoon Neliapila Oy | Real estate | 2019 |
| Porvoon Offsetpaino Oy | Manufacturing | 1990 |