| Metsäosakeyhtiö Koirsalo Oy | Agriculture & fishing | 2010 |
| Metsäpalvelu J. Konttinen Oy | Agriculture & fishing | 2012 |
| Midas Machinery Oy | Wholesale & retail | 2013 |
| Mielenterveyspalvelujen Osk. Friend | Health & social care | 2014 |
| Mika Elomäki Oy | Wholesale & retail | 1983 |
| Mika Siekkinen Oy | Arts & recreation | 1989 |
| Mikko Kervinen Oy | Wholesale & retail | 2014 |
| Mikko Nurmela Ky | | 1973 |
| Mikos Learning Programs Oy | Education | 1997 |
| Mikufinn Oy | Arts & recreation | 2025 |
| Millistudio Oy | Professional & scientific | 1991 |
| MinnaÄssä Oy | Wholesale & retail | 1984 |
| Minnom Oy | Professional & scientific | 2016 |
| Mioks Oy | Arts & recreation | 2008 |
| Missparaskeva Oy | Arts & recreation | 2021 |
| MoiVain Oy | Administrative & support | 1982 |
| Monialayhtiö Reni Oy | Real estate | 1980 |
| Mopro Oy | Transport & logistics | 1983 |
| Morten Priks Oy | Agriculture & fishing | 2025 |
| Muna.io Oy | Information & communication | 2021 |
| Muovi Team S & H Kontinen Oy | Manufacturing | 1986 |
| Murto-Rakennus Oy | Construction | 2018 |
| MutCat Design House Oy | Professional & scientific | 2021 |
| Myynti ja markkinointi J2B Oy | Financial services | 2018 |
| Mäenpää Trade Oy | Real estate | 2020 |
| NBXVIRA oy | Other services | 2025 |
| NGW Solutions Oy | Water & waste | 2025 |
| NMN Sports Nutrition Oy | Wholesale & retail | 2024 |
| NMR Technologies Oy | Manufacturing | 2024 |
| NailBox Oy | Other services | 2020 |
| Nalle Rakennus Ky | Construction | 2008 |
| Nana's Thai Food oy | Hospitality | 2020 |
| Nastapimu Oy | Manufacturing | 2007 |
| Natura Lapponiae Oy | Wholesale & retail | 2020 |
| Nauticruiser Oy | Administrative & support | 1990 |
| Navigen Oy | Education | 1999 |
| Nedis Oy | Wholesale & retail | 1981 |
| NeuvoTek Oy | Professional & scientific | 2004 |
| Niittylahden vesiosuuskunta | Water & waste | 2001 |
| Nilsson & Kälviäinen Oy | Health & social care | 2015 |
| NoVe Kiinteistöt Oy | Real estate | 2021 |
| Nonvest Oy | Financial services | 2018 |
| Nordic Actuarial Solutions Oy | Financial services | 2025 |
| Nordic Core Oy | Information & communication | 1997 |
| Nordic Dahl Welding Oy | Manufacturing | 2026 |
| Nordic Fivie Oy | Hospitality | 2019 |
| Nordic Kivi Oy | Other services | 2018 |
| Nordic Lion Holding Oy | Financial services | 2026 |
| Nordic Marten Oy | Wholesale & retail | 2025 |
| Norelco Group Oy | Manufacturing | 2014 |
| Norelco Oy | Manufacturing | 2026 |
| Norppa Taskinen Ky | Professional & scientific | 2010 |
| Norppaland Oy | Professional & scientific | 2010 |
| Noucon Oy | Construction | 1999 |
| Nova Records Oy | Information & communication | 2007 |
| Nuopponen Invest Oy | Real estate | 2021 |
| Ny Nyslott Oy | Wholesale & retail | 2026 |
| OK35 Invest Oy | Real estate | 1993 |
| Olutasioita M. Pulliainen OY | Wholesale & retail | 1993 |
| Ormel OY | Wholesale & retail | 2005 |
| OT Asennus Oy | Construction | 2017 |
| Ohjaus- ja koulutuspalvelu Kerä Oy | Education | 2021 |
| Olaf Castle Oy | Real estate | 2022 |
| Olavin Nahka ja Laukku Oy | Manufacturing | 2025 |
| Olga Maria Oy | Wholesale & retail | 2010 |
| Olivias second Hand oy | Wholesale & retail | 2020 |
| Olutravintola Sillansuu Oy | Hospitality | 2005 |
| Ompelualan erikoisliike VIKA&TIKKI OY | Wholesale & retail | 2007 |
| Onnellinen porsas Oy | Health & social care | 2024 |
| Onnellinenhymy Oy | Health & social care | 2016 |
| Onnenkengän Kiinteistöt Oy | Real estate | 2001 |
| Optideli Ky | Wholesale & retail | 2002 |
| Optikko B. Lohman Oy | Wholesale & retail | 1957 |
| Optikko J. Liimatta Oy | Administrative & support | 2024 |
| Oravin Vesiosuuskunta | Water & waste | 2003 |
| Osuuskunta Headick | Arts & recreation | 2011 |
| Ovaskala Oy | Hospitality | 2006 |
| Oy Esmarin Composites Ltd | Manufacturing | 2009 |
| Oy JATTEC Ab | Manufacturing | 2004 |
| Oy Loppo Production Ltd | Manufacturing | 1996 |
| Oy Marina Group Ltd | Transport & logistics | 2015 |
| Oy Okabex Ab | Arts & recreation | 1993 |
| Oy Olavila | Real estate | 1953 |
| Oy Savon Mafia Ab | Hospitality | 1997 |
| Oy Vip Cruise Ltd | Transport & logistics | 1989 |
| P&M&J Kervinen Oy | Transport & logistics | 1991 |
| P&N&J invest Oy | Construction | 2012 |
| P-A Yhtiöt Oy | Construction | 2017 |
| P. Konnu Oy | Transport & logistics | 2016 |
| Pascual Cuisine Ky | Hospitality | 2025 |
| PDP Yrityspalvelut Oy | Professional & scientific | 2011 |
| PIH-Data Oy | Wholesale & retail | 1988 |
| PJP kuvaamo Oy | Professional & scientific | 1997 |
| PKS Camping Oy | Hospitality | 2015 |
| PL Rakennus ja Remontointi Oy | Construction | 2015 |
| PM-Laskenta Oy | Professional & scientific | 2004 |
| PN Invest Oy | Real estate | 2017 |
| POP Pihasuunnittelua Oy | Other services | 2014 |
| PPMV Invest Oy | Administrative & support | 2023 |
| PR Terveyspalvelut OY | Health & social care | 2007 |