| Ministore Oy | Real estate | 2019 |
| Misimo Oy | Wholesale & retail | 2009 |
| MitJas Oy | Financial services | 2019 |
| Mitra Imatran Rakennuttaja Oy | Real estate | 2021 |
| Mitra Management Oy | Real estate | 1998 |
| Modulor oy ltd | Financial services | 1995 |
| Monitaitoinen Oy | Construction | 2024 |
| Morabia Oy | Wholesale & retail | 1994 |
| MotoTuuli Oy | Arts & recreation | 2017 |
| Multitasking Paradice Oy | Construction | 2025 |
| Murax Oy | Construction | 2008 |
| Music-Bros avoin yhtiö | Information & communication | 1988 |
| Muuraus Heikura Oy | Construction | 1995 |
| Myllys Yhtiöt Oy | Other services | 1983 |
| NB Express Oy | Wholesale & retail | 2009 |
| NK Palvelu Ky | Administrative & support | 2007 |
| NN Media avoin yhtiö | Arts & recreation | 2024 |
| Narripelit Oy | Arts & recreation | 2024 |
| Neitsytniemen Kartano Oy | Hospitality | 2019 |
| Neovo Solutions Oy | Professional & scientific | 2008 |
| New Life Vuoksi Oy | Wholesale & retail | 2015 |
| New Port Imatra Oy | Real estate | 2015 |
| NikAnton Kiinteistöt Oy | Real estate | 2023 |
| Niskan Autotalo Oy | Real estate | 2005 |
| Niskan Huolto Oy | Other services | 2018 |
| Niskan Hydrauliikka ja Raskasosa Oy | Wholesale & retail | 2005 |
| Niskan Varaosa, Ilkka Korhonen Ky | Wholesale & retail | 1983 |
| Niskan Vuokratilat Oy | Real estate | 2000 |
| NorDoc Ky | Health & social care | 2019 |
| Nordic City Oy | Real estate | 2008 |
| Nordic Denim House Oy | Professional & scientific | 2008 |
| North Recycling Oy | Administrative & support | 2024 |
| NortrenDT Oy | Manufacturing | 2023 |
| NtCom-NT Oy | Information & communication | 2020 |
| Näträmälän Kuljetus Ky | Transport & logistics | 1987 |
| Näönvuoksi Oy | Wholesale & retail | 2007 |
| OC Bar Oy | Hospitality | 2008 |
| Oinarent Oy | Real estate | 2021 |
| Olipas Investment Oy | Hospitality | 2018 |
| Optikko Kaseva Oy | Financial services | 1983 |
| Ordo One AB, sivuliike Suomessa | Information & communication | 2023 |
| Osuuskunta SaimaanVirta | Other services | 2006 |
| Osuuskunta Vuoksen Taitajat | Education | 2015 |
| Otso Dynamics Oy | Construction | 2026 |
| Ouro Stories Oy | Information & communication | 2024 |
| Ovako Finland Oy Ab | Professional & scientific | 2010 |
| Ovako Imatra Oy Ab | Manufacturing | 2006 |
| Oy Biomar Ab | Wholesale & retail | 1995 |
| Oy Rainbow Comfort Ltd | Manufacturing | 2017 |
| Oy River Steel Ltd. | Manufacturing | 2023 |
| Oy Saimaa Life Ltd | Construction | 2012 |
| Oy Scan Fibre Ltd | Professional & scientific | 1990 |
| Oy Scandinavian Merchandise Center broking & trading Ltd. | Wholesale & retail | 1985 |
| Oy Vilma Development Ltd | Real estate | 2017 |
| Park Expert Finland OY | Arts & recreation | 2002 |
| PH Works Oy | Manufacturing | 2022 |
| PK Sähkösuunnittelu ja Asennus Oy | Professional & scientific | 2020 |
| PLH-Kiinteistöpalvelut Oy | Administrative & support | 2019 |
| PR Taloudenhallinta Oy | Professional & scientific | 2020 |
| PRA Invest Oy | Financial services | 2020 |
| PROITBU Oy | Other services | 2025 |
| PUUMAS Oy | Real estate | 2014 |
| PV Monitoimi Oy | Administrative & support | 2024 |
| Paarukka Oy | Real estate | 2026 |
| Palvelukoti Onnela Oy | Health & social care | 1994 |
| Pants Bear Oy | Information & communication | 2023 |
| Paper Prologix Oy | Professional & scientific | 2023 |
| Paperharju Oy | Professional & scientific | 2004 |
| Patterinniemen Vesiosuuskunta | Water & waste | 2026 |
| Pelihuone 109 OY | Arts & recreation | 2025 |
| Pelkolan Terminaali Oy | Transport & logistics | 2000 |
| Peltinalle Oy | Construction | 2022 |
| Perhekoti Kuutti Oy | Health & social care | 2005 |
| Pertti Hämäläinen Oy | Financial services | 1977 |
| PesuLappee Oy | Other services | 2008 |
| Petri Lempiäinen Ky | Wholesale & retail | 2004 |
| Pietarintien Autohuolto Oy | Other services | 2020 |
| Piha ja Koti kuntoon Oy | Administrative & support | 2025 |
| Pihlman Kiinteistöt Oy | Real estate | 2020 |
| Piitekno Oy | Manufacturing | 2020 |
| Pilatesstudio Soma Oy | Arts & recreation | 2026 |
| Pillin tila Oy | Agriculture & fishing | 2023 |
| Pin High Oy | Transport & logistics | 1992 |
| Pirkka-Ollonen Oy | Professional & scientific | 2016 |
| Pirkkolan perhekoti Avoin yhtiö | Health & social care | 2007 |
| Pixel Networks Suomi Oy | Information & communication | 2024 |
| Plastnor Oy | Manufacturing | 2007 |
| Pochta.fi Oy | Transport & logistics | 2014 |
| Pohjolan Autoturva Oy | Wholesale & retail | 2019 |
| Poppaset Oy | Administrative & support | 2015 |
| Power Link Finland Oy | Manufacturing | 2011 |
| Prima Global Market Oy | Wholesale & retail | 2020 |
| Primal Solution Oy | Information & communication | 2024 |
| Pro Kaukopään koulu Oy | Real estate | 2020 |
| ProRahtinen Oy | Transport & logistics | 2023 |
| Profiten Oy | Transport & logistics | 2005 |
| Pumppu Center Oy | Manufacturing | 2022 |
| Pumppuhuolto Savolainen Oy | Water & waste | 2016 |
| Puusepänliike A. Asikainen Ky | Manufacturing | 1996 |
| Pölyhuiska Oy | Administrative & support | 2023 |