| Picard Investment Oy | Financial services | 2019 |
| PicoX Oy | Wholesale & retail | 2013 |
| Piece of Property Oy | Real estate | 2024 |
| Pienvenesatama Punainen Mylly Oy | Transport & logistics | 2020 |
| Pienvenesatama Punaisen Myllyn Laiturit Toppilansalmi Oy | Real estate | 2021 |
| Pietarilan Maarakennus Oy | Administrative & support | 1976 |
| Pietilä Ky | Information & communication | 1987 |
| Pietilän Kuljetus Ky | Information & communication | 1983 |
| Pietola Consulting Oy | Professional & scientific | 2017 |
| PigloBoutique Oy | Professional & scientific | 2021 |
| PihaYkköset Oy | Construction | 2018 |
| Pihahuolto A.Vuoti Oy | Administrative & support | 2026 |
| Pihkassa Musiikkituotanto avoin yhtiö | Information & communication | 2016 |
| Pihlaja Catering Oy | Hospitality | 2009 |
| Pihlaja Invest Oy | Real estate | 2019 |
| Pihlakero Oy | Real estate | 1999 |
| Piia Savola Oy | Wholesale & retail | 2013 |
| Piippo infra Oy | Wholesale & retail | 2024 |
| Piippu Hermanni Ky | Administrative & support | 2025 |
| Piiruukki Oy | Information & communication | 1988 |
| Piisku Oy | Information & communication | 2021 |
| Piki Kiinteistöt Oy | Real estate | 2017 |
| Piki10 Oy | Professional & scientific | 2014 |
| Pikisaari Asunnot Oy | Real estate | 2025 |
| Pikkaralan Frisbeepuisto-osuuskunta | Arts & recreation | 2015 |
| Pikkaralan Panimo Oy | Manufacturing | 2025 |
| Pikkaralan Pysäkki Oy | Wholesale & retail | 2024 |
| Pikkaralan Vesiosuuskunta | Water & waste | 1969 |
| Pikku Hakin Sijoitus Oy | Financial services | 2006 |
| Pikkuaakkoset holding Oy | Financial services | 2025 |
| Pikkulahden Palvelut Oy | Administrative & support | 2011 |
| Pilot Business Park Oy | Real estate | 2000 |
| Pilviotus Oy | Information & communication | 2018 |
| Pine Group Oy | Administrative & support | 2011 |
| Pink IES Oy | Administrative & support | 2022 |
| Pinoma Oy | Real estate | 2017 |
| Pint Please Global Oy | Information & communication | 2014 |
| Pintakeskus Oy | Administrative & support | 2024 |
| Pintapartner Oy | Construction | 2022 |
| Pionity Oy | Arts & recreation | 2025 |
| Pipelife Finland Oy | Manufacturing | 1987 |
| Pirjo ja Timo Kyllinen Oy | Real estate | 2023 |
| Pirkko Warppe Ky | Professional & scientific | 1996 |
| Pirkko ja Jukka Ruusu Oy | Financial services | 1987 |
| Pirpana Ky | Real estate | 1987 |
| Pirssipiste avoin yhtiö | Wholesale & retail | 2019 |
| Pitkä Mieli Oy | Health & social care | 2023 |
| Pitomaalaus Julkisivut Oy | Construction | 2025 |
| Pitomaalaus Oy | Construction | 2010 |
| Pivis Vintage Oy | Wholesale & retail | 2022 |
| Pizza Boys Oy | Hospitality | 2016 |
| Pizza Liiga Oy | Hospitality | 2026 |
| Pizzeria Lila Oy | Hospitality | 2018 |
| Pizzeria Maikkulan Milan Avoin yhtiö | Hospitality | 2009 |
| Pizzeria-ravintola Tarantella avoin yhtiö | Hospitality | 1992 |
| Plaana-korttelin Parkki Oy | Transport & logistics | 2021 |
| Place diva Oy | Other services | 2003 |
| Plan B Holding Oy | Financial services | 2021 |
| Plan-Air Oy | Professional & scientific | 2016 |
| Planora Oy | Professional & scientific | 1988 |
| Plastic Surgery Center North Oy | Health & social care | 2022 |
| Plastic Surgery Center Oulu Oy | Health & social care | 2009 |
| Plastiikkakirurgia Varonen Oy | Health & social care | 2020 |
| PlayGain Oy | Information & communication | 2015 |
| Playbike Oy | Wholesale & retail | 2010 |
| Pleasure Solutions Oy | Information & communication | 2022 |
| Plebeian Studio Oy | Information & communication | 2024 |
| Pleesy LTD. Oy | Information & communication | 2024 |
| Plumbarius Oy | Financial services | 2025 |
| Plusfi Oy | Professional & scientific | 2012 |
| Plusmark Oy | Professional & scientific | 1979 |
| Po5 Oy | Financial services | 2026 |
| Pohjalainen Kirjakauppa Oy | Real estate | 1931 |
| Pohjan Group Oy | Transport & logistics | 2019 |
| Pohjan Lihatuote Ky | Manufacturing | 1998 |
| Pohjan Liikehuoneistot Oy | Real estate | 2014 |
| Pohjan Polaria Productions Oy | Arts & recreation | 2014 |
| PohjanAitta Oy | Administrative & support | 2024 |
| Pohjanmaan HC-Consulting Ky | Professional & scientific | 2008 |
| Pohjanmaan Kiinteistökehitys Oy | Real estate | 2013 |
| Pohjanmaan PHR-rakennus Oy | Construction | 2008 |
| Pohjanmaan Talotekniikka Oy | Construction | 2011 |
| Pohjanpojat Oy | Agriculture & fishing | 2025 |
| Pohjanvilja Oy | Real estate | 2018 |
| Pohjoinen A-ryhmä Oy | Professional & scientific | 2005 |
| Pohjoinen Suunnittelutoimisto Oy | Information & communication | 2022 |
| Pohjoinen kauneus Oy | Other services | 2021 |
| Pohjois-In Oy | Financial services | 1989 |
| Pohjois-Pohjanmaan LVI1 Oy | Construction | 1994 |
| Pohjois-Pohjanmaan Löytötavarapalvelut Oy | Administrative & support | 2010 |
| Pohjois-Pohjanmaan oshp Oy | Administrative & support | 2013 |
| Pohjois-Suomen Asetekniikka Ky | Transport & logistics | 1990 |
| Pohjois-Suomen Asuntokeskus Oy | Real estate | 1995 |
| Pohjois-Suomen Elektroniikkakeskus Oy PSEK | Wholesale & retail | 2014 |
| Pohjois-Suomen Habita Oy | Real estate | 2002 |
| Pohjois-Suomen Hinauspalvelu Ky | Transport & logistics | 2004 |
| Pohjois-Suomen Kiinteistökehitys Oy | Real estate | 2025 |
| Pohjois-Suomen Kiinteistösijoitus Oy | Real estate | 2011 |
| Pohjois-Suomen Kiinteistötoimisto Oy | Professional & scientific | 1994 |
| Pohjois-Suomen Kotiapu ja Hoitopalvelut Oy | Health & social care | 2009 |