| P-talo Kirkkokatu 26 B Oy | Transport & logistics | 2007 |
| P. Räsänen Oy | Real estate | 1993 |
| P.R. & Rauta Oy | Administrative & support | 2023 |
| PAL Finland Oy | Wholesale & retail | 2014 |
| Pemali OY | Wholesale & retail | 2022 |
| PEM Holdings Oy | Financial services | 2023 |
| PIMT Group II Oy | Professional & scientific | 2025 |
| PJK-Service Ky | Hospitality | 2003 |
| PK Forest Oy | Agriculture & fishing | 2017 |
| PK Media Service Oy | Professional & scientific | 2002 |
| PK:n Taksi Oy | Transport & logistics | 1995 |
| PKF Holding Oy | Financial services | 2020 |
| PKR-Tekniikka Oy | Construction | 2017 |
| PKS Sähkönsiirto Oy | Energy | 2006 |
| PLP Pääkkönen Oy | Manufacturing | 1984 |
| PM Ravintolat Oy | Hospitality | 2019 |
| PMB Portal Oy | Information & communication | 2025 |
| PP WireTech Oy | Manufacturing | 2013 |
| Primagency OY | Wholesale & retail | 2013 |
| PT-Controlnet Oy | Information & communication | 1993 |
| PTP Holding Oy | Real estate | 2024 |
| PVS-Holding Oy | Financial services | 2023 |
| PaNoRaK Oy | Construction | 2020 |
| Paavilainen-Hassinen Oy | Professional & scientific | 2025 |
| Pactum Oy | Financial services | 1990 |
| Paikkatietopiste Net Oy | Professional & scientific | 2017 |
| Paino-Tuatot Oy | Manufacturing | 1992 |
| Painokanava Oy | Manufacturing | 1982 |
| Paja Training Oy | Arts & recreation | 2025 |
| Palmionet Oy | Information & communication | 2004 |
| Palveluyhtiö LR Oy | Administrative & support | 2008 |
| Pankkitalon Parkki Oy | Real estate | 1997 |
| Papsor Oy | Financial services | 1997 |
| Parturi-Kampaamo Galleria 62 Oy | Other services | 2020 |
| Parturi-Kampaamo Hiustiimi Ky | Other services | 2014 |
| Parturi-Kampaamo SK Unik Oy | Other services | 2011 |
| Parturi-Kampaamo Wastaanotto Oy | Other services | 2026 |
| Parturi-Kampaamo Ykköspaikka Ky | Other services | 2005 |
| Pasanen Enterprise Oy | Information & communication | 2016 |
| Pasari Ravintolat Oy | Hospitality | 2008 |
| Pasi's Fantastic Hobbies Oy | Arts & recreation | 2025 |
| Pasmari Oy | Wholesale & retail | 1994 |
| Paula Marjakangas Ky | Real estate | 1987 |
| Paxot Oy | Wholesale & retail | 2005 |
| Pe-Kate Oy | Real estate | 1978 |
| Pedler Ky | Wholesale & retail | 1998 |
| Peikonmarja avoin yhtiö | Health & social care | 1997 |
| Pejun Kuljetus Oy | Transport & logistics | 2010 |
| Pekka Koukkari Investment Oy | Financial services | 2007 |
| Peltiliike Vänskä Oy | Construction | 2015 |
| Pelule investments Oy | Professional & scientific | 2024 |
| PelvicExperts Oy | Health & social care | 2026 |
| Pemp Oy | Manufacturing | 2025 |
| Penluk Oy | Real estate | 1989 |
| Pentin Paja Oy | Manufacturing | 1982 |
| Penttilän Puu Oy | Manufacturing | 2003 |
| Peremmälle Oy | Professional & scientific | 2021 |
| Personale Oy | Administrative & support | 2020 |
| Pertti Toropainen Ky | Wholesale & retail | 1989 |
| Peräharju Oy | Real estate | 1993 |
| Pesuainekauppa Kettunen Oy | Wholesale & retail | 2010 |
| Petri O. Nevalainen Ky | Construction | 1990 |
| Phann Oy | Manufacturing | 1987 |
| Pharmasa Oy | Wholesale & retail | 2015 |
| Pictoure Oy | Administrative & support | 2014 |
| Pielisen Kiinteistö Oy | Real estate | 1990 |
| Pielisensuun isännöinti Oy | Real estate | 2017 |
| Pietarinen & Pyykkö Oy | Financial services | 2021 |
| Pietilä Kodit Oy | Real estate | 2021 |
| Pihatyö Nuutinen Oy | Construction | 1982 |
| Piikkikasvi Production Ky | Arts & recreation | 1984 |
| Piirtoa Oy | Construction | 2021 |
| Pikseli Advanced Network Solutions Oy | Financial services | 1997 |
| Pilkontie Kiinteistöt Oy | Real estate | 2025 |
| Pintaykköset Oy | Construction | 2018 |
| Pippurinpolku Oy | Hospitality | 2014 |
| Pirantti Oy | Financial services | 2025 |
| Pirisen Leipomo Oy | Hospitality | 2024 |
| Piristin osk | Other services | 2025 |
| Pisarat JNS Oy | Construction | 2020 |
| Pitkänen Yhtiöt Oy | Real estate | 2010 |
| Pizzeria Roihu Oy | Hospitality | 2016 |
| Plastiikkakirurgia Martikainen Oy | Health & social care | 2008 |
| Plexman oy | Professional & scientific | 2016 |
| Plus Jussila Oy | Professional & scientific | 2017 |
| Pocket Manager Finland Oy | Information & communication | 2019 |
| Pocomic Trading Oy | Hospitality | 1991 |
| PodoPiste - Jalkaterapiapalvelut Oy | Health & social care | 2024 |
| Pohjan Tytär Oy | Hospitality | 2021 |
| Pohjois-Karjalan Energiaholding Oy | Financial services | 2000 |
| Pohjois-Karjalan Marttapalvelut Oy | Health & social care | 2011 |
| Pohjois-Karjalan Napakka Osk | Administrative & support | 2004 |
| Pohjois-Karjalan Neon Oy | Manufacturing | 2012 |
| Pohjois-Karjalan Osuuskauppa | Wholesale & retail | 1919 |
| Pohjois-Karjalan Osuuspankki | Financial services | 2008 |
| Pohjois-Karjalan Sähkö Oy | Energy | 1946 |
| Pohjois-Karjalan terveyspalvelut Oy | Health & social care | 2012 |
| Pohjoispärnä Oy | Real estate | 1977 |
| Pohjolan Rakennustaito Oy | Real estate | 1995 |
| Pohjolan Rengas Oy | Wholesale & retail | 1972 |