| KotiMattila Oy | Other services | 2021 |
| KotiPiian ikääntyvien palvelut Oy | Hospitality | 2021 |
| Kotisi Sähköpalvelu Oy | Construction | 2016 |
| Kuinka Oy | Professional & scientific | 2021 |
| Kukantita Oy | Professional & scientific | 2020 |
| Kukka-Kimppula Oy | Wholesale & retail | 2026 |
| Kuljetus Eelis Ylijoki Ky | Transport & logistics | 1980 |
| Kuljetus Einola Ky | Transport & logistics | 1987 |
| Kuljetus Hintikka Oy | Transport & logistics | 2005 |
| Kuljetus Merioksa Oy | Transport & logistics | 1996 |
| Kuljetus Mikko Heinonen Oy | Transport & logistics | 2015 |
| Kuljetus Säteri Oy | Transport & logistics | 2017 |
| Kuljetus-Jalava Ky | Transport & logistics | 2005 |
| Kuljetus-Salminen Ky | Transport & logistics | 1982 |
| Kultahammas Oy | Health & social care | 2024 |
| Kuntokeskus Kanava Oy | Arts & recreation | 2008 |
| Kuokka & Kosla Paasikivi Oy | Construction | 2007 |
| Kuva ja Kehys Lahti Ky | Wholesale & retail | 1988 |
| Kuvapalvelu Epics Oy | Professional & scientific | 2016 |
| Kybertaito Oy | Information & communication | 2022 |
| Kylmäset Oy | Manufacturing | 1973 |
| LBMuuraus Oy | Construction | 2024 |
| LK Tasoite ja Rappaus Oy | Construction | 2018 |
| LK Urakointi Oy | Construction | 1988 |
| LK Yhtiöt Oy | Construction | 2013 |
| LKV Toiveasunnot Om. P. Järvenpää Oy | Financial services | 1998 |
| LLH Fit Oy | Arts & recreation | 2024 |
| LT vakuutus Oy | Financial services | 2023 |
| Laakso Capital Management Oy | Professional & scientific | 2024 |
| Laatuverkko Oy | Construction | 2024 |
| Laine Ventures Oy | Real estate | 2023 |
| Lakiasiaintoimisto Notio Oy | Professional & scientific | 2024 |
| Lapinniemen Kahvila Oy | Real estate | 1996 |
| Levy- ja teräsrakenne Horsmalahti Oy | Manufacturing | 1976 |
| Lift-Te Oy | Wholesale & retail | 2014 |
| LiikkuVille Oy | Administrative & support | 2011 |
| Liimatainen Racing Team Oy | Professional & scientific | 1993 |
| Lingerie Finland Oy | Wholesale & retail | 2003 |
| Linnunradan Nomadi Oy | Information & communication | 2023 |
| Lintulan & Kumppanit Oy | Professional & scientific | 2026 |
| Live-action Entertainment Oy | Arts & recreation | 2026 |
| Lixiaozhou Oy | Financial services | 2025 |
| Lograr Oy | Professional & scientific | 2023 |
| Loopware Oy | Professional & scientific | 2002 |
| LujaParts Oy | Professional & scientific | 2024 |
| Lähelläsi Oy | Health & social care | 2020 |
| LämmönJakajat Oy | Construction | 2023 |
| Lääkekulma Oy | Wholesale & retail | 2025 |
| M&M Henkilöstöratkaisut Oy | Administrative & support | 2024 |
| M.A.K. Invest Oy | Financial services | 1990 |
| MANA Valmennus Oy | Education | 2024 |
| Mesocom OY | Manufacturing | 2020 |
| MJR Yhtiöt Oy | Administrative & support | 2021 |
| MJSS Invest Oy | Real estate | 2020 |
| MKM-Tech. Oy | Wholesale & retail | 1988 |
| MPS Nieminen Oy | Financial services | 2004 |
| MRH Rakennus Oy | Construction | 2022 |
| MSSK Holding Oy | Professional & scientific | 2024 |
| MTX Audio Oy | Arts & recreation | 2024 |
| Maanrakennus Pöytäkivi Oy | Construction | 1982 |
| Maansiirto Tynskä Ky | Construction | 1980 |
| Mainos ja Paperi Pelkonen Oy | Wholesale & retail | 2007 |
| Malkki Group Oy | Construction | 2020 |
| Mallas-Pidot Oy | Hospitality | 2004 |
| Mama's Bar&Bistro Oy | Hospitality | 2009 |
| Mansikan Isännöinti Oy | Real estate | 2018 |
| Marikoo Kotisivuratkaisut Oy | Professional & scientific | 2025 |
| Markkinointi- ja mainostoimisto Pupellino Oy | Professional & scientific | 2011 |
| Masan Autotarvike Oy | Wholesale & retail | 2002 |
| Math Ventures Oy | Financial services | 2026 |
| Matias Evikoski Oy | Wholesale & retail | 2022 |
| MeTree Educating Oy | Education | 2019 |
| MedTech-Wessman Oy | Manufacturing | 2022 |
| Mekkomafia Oy | Wholesale & retail | 2019 |
| Memefox Logistics Oy | Transport & logistics | 2024 |
| Merikristalli Oy | Health & social care | 2018 |
| Metritiski Oy | Construction | 2011 |
| MiJuVa Oy | Professional & scientific | 2022 |
| Mianpaikka Oy | Hospitality | 2024 |
| Mittrix Oy | Manufacturing | 1973 |
| Modermax Avoin Yhtiö | Wholesale & retail | 2021 |
| Moonlake Apps Oy | Information & communication | 2012 |
| Mottis Oy | Real estate | 2012 |
| MoveLog OY | Education | 2025 |
| Muovityö Hiltunen Oy | Manufacturing | 1990 |
| Mustion media Oy | Education | 2007 |
| My Custom Sports Chair Finland Oy | Wholesale & retail | 2021 |
| Myssy Märkänä Oy | Arts & recreation | 2021 |
| NAISSO Oy | Professional & scientific | 2009 |
| NP-Kodit Oy | Real estate | 2023 |
| NeuwoGas Oy | Professional & scientific | 2025 |
| Nice Living Oy | Real estate | 2024 |
| NikOMT Oy | Health & social care | 2003 |
| NollaMarkka Oy | Wholesale & retail | 2012 |
| NordicFrame Oy | Construction | 2016 |
| Nordkulla Real Estate Investor Oy | Real estate | 2026 |
| North Silver Boats Finland Oy | Wholesale & retail | 2019 |
| Nosto- ja Kuljetus Jokela Ky | Transport & logistics | 1986 |
| Nostokaulus Oy Räsänen | Manufacturing | 1982 |
| Nuohousliike Riihimäki Oy | Administrative & support | 2021 |