| Oulunsalo Parturi Oy | Other services | 2021 |
| Oulunsalon Airo Market Ky | Wholesale & retail | 1991 |
| Oulunsalon Ale-Hinta, avoin yhtiö | | 1986 |
| Oulunsalon Rakennus KY | Construction | 1993 |
| Oulunsalon Ratsastuskoulu Oy | Arts & recreation | 2006 |
| Oulunsalon Rohdos Oy | Wholesale & retail | 2020 |
| Oulunsalon Sähköosuuskunta | Energy | 1923 |
| Oulunsalon Tilitoimisto Oy | Professional & scientific | 2015 |
| Oulunsalon pientilat Oy | Real estate | 2013 |
| Oulunsalon ranta Oy | Real estate | 2010 |
| Oy Scandic Homes Ltd | Construction | 1987 |
| PAM-Markkinointi Oy | Construction | 2000 |
| PJ Advance Oy | Professional & scientific | 2007 |
| PKS Kuivaustekniikka Oy | Professional & scientific | 2025 |
| PM Automyynti Oy | Wholesale & retail | 2018 |
| PO-Koti Oy | Construction | 2005 |
| PRE-Sijoitus Oy | Real estate | 2019 |
| PS-Design Finland Oy | Wholesale & retail | 2011 |
| PV-Urakointi Oy | Transport & logistics | 2019 |
| Paineilmapalvelu Taito Ullakko Oy | Construction | 2001 |
| Paljusauna Oy | Administrative & support | 2015 |
| Parrila Ky | Construction | 1994 |
| Paseri Oy | Manufacturing | 2026 |
| Pasta Miller Productions Oy | Information & communication | 2008 |
| PeCA Oy | Professional & scientific | 2014 |
| Peclit Ltd Oy | Professional & scientific | 1997 |
| Peki-Invest Oy | Financial services | 2011 |
| Perämeri Catering Oy | Hospitality | 2020 |
| Pilot Invest Oy | Energy | 2025 |
| Pilotti Group Oy | Professional & scientific | 2026 |
| Pinto Design Oy | Professional & scientific | 2015 |
| Pinto Technology Oy | Professional & scientific | 2009 |
| Pitopalvelu Timonen Oy | Hospitality | 2012 |
| Plaan Consult Oy | Professional & scientific | 2012 |
| Pohjois-Suomen Eristys Oy | Construction | 1966 |
| Pohjois-Suomen Kuriiripalvelu Oy | Transport & logistics | 2022 |
| Pohjolan Hitsihuolto Oy | Manufacturing | 1988 |
| Pohjolan Pikalinjat Oy | Transport & logistics | 2014 |
| Pohjolan Talovaruste Oy | Construction | 2026 |
| Polar-Lahja Oy | Manufacturing | 1981 |
| Potero Invest Oy | Hospitality | 2021 |
| Powre Oy | Professional & scientific | 2016 |
| Prestia Oy | Professional & scientific | 1988 |
| Presto Artist & Consulting Oy | Wholesale & retail | 2003 |
| Procomp Solutions Oy | Information & communication | 2024 |
| Profes Finland Oy | Professional & scientific | 1999 |
| Promotive Rehabilitation Ergo Oy | Education | 2017 |
| Proventia Group Oyj | Manufacturing | 2000 |
| Proventia Oy | Manufacturing | 1994 |
| Pukema Engineering Oy | Other services | 2005 |
| Pulse Finland Oy | Manufacturing | 2004 |
| Puusepänliike Eurokaluste Oy | Manufacturing | 2006 |
| Pyörä-Juka Ky | | 1958 |
| Päiväkoti Villivadelma Oy | Education | 1999 |
| R4C-Global Oy | Professional & scientific | 2021 |
| RAE-Betoni Oy | Construction | 2013 |
| Raydata OY | Professional & scientific | 2018 |
| RNCap Solutions Oy | Administrative & support | 2023 |
| RP-Pumput Oy | Manufacturing | 2021 |
| RPH Asennus Oy | Construction | 2022 |
| RPH Capital Oy | Financial services | 2026 |
| RPH Infra Oy | Construction | 2026 |
| RaapWare Oy | Real estate | 2022 |
| RackStaff Oy | Administrative & support | 2024 |
| Rakennus Kolibri Oy | Construction | 2017 |
| Rakennus Takalahti Oy | Construction | 1988 |
| Rakennus-Hanka Oy | Construction | 2012 |
| Rakennuspalvelu HM Impola Oy | Construction | 2020 |
| Rakennuspalvelu Huikari Oy | Construction | 2006 |
| Rakennuspalvelu J. Eskola Oy | Construction | 2013 |
| Rakennuspalvelu Maperak Ky | Construction | 2006 |
| Rapidi Invest Oy | Financial services | 2026 |
| Real Kids Oy | Hospitality | 2010 |
| Redimark Oy | Real estate | 1993 |
| Retkivuokraamo Oy | Administrative & support | 2021 |
| Revendia Ky | Professional & scientific | 2014 |
| Risera Oy | Financial services | 1991 |
| Rivet Invest Oy | Professional & scientific | 2022 |
| Rollout Oy | Information & communication | 2022 |
| SHJ Group Oy | Transport & logistics | 2014 |
| SJ Audit Oy | Professional & scientific | 2018 |
| SP Invest Oy | Professional & scientific | 2018 |
| SUP Demolition Oy | Construction | 2015 |
| SUP GROUP Oy | Construction | 2014 |
| SUP Installation Oy | Construction | 2015 |
| SaMaP Oy | Professional & scientific | 2025 |
| Saaga Travel Oy | Transport & logistics | 2008 |
| Saagacoms Oy | Professional & scientific | 2019 |
| Saipot Oy | Financial services | 2023 |
| Sakeanmakea Oy | Hospitality | 2023 |
| Salon Pohjaranta Oy | Other services | 2011 |
| Salonpään Sähköosuuskunta | Energy | 1952 |
| Saltboys Oy | Administrative & support | 2025 |
| SamAns Logistic Oy | Financial services | 2022 |
| SamSam uinti Oy | Arts & recreation | 2024 |
| Sarpan Kotihoito Oy | Health & social care | 2021 |
| Saumark Oy | Wholesale & retail | 1992 |
| Shine Group Oy | Hospitality | 2022 |
| Side Quest Holding Oy | Professional & scientific | 2025 |
| Sijoitus Aalto Oy | Financial services | 2023 |