| Kotona Manor Oy | Hospitality | 2018 |
| Kraemer Oy | Transport & logistics | 2015 |
| Kukkakauppa & Hautauspalvelu Peräkylä Oy | Other services | 1993 |
| Kukkoleipomo Mamma ja Tytöt Ky | Manufacturing | 2009 |
| Kuljetus Harri Pulkkinen Ky | Transport & logistics | 1979 |
| Kuljetus Jukka Haaja Ky | Transport & logistics | 1985 |
| Kuljetus Kauhanen Oy | Transport & logistics | 1991 |
| Kuljetus Raimo Tuomainen Oy | Transport & logistics | 1997 |
| Kuljetus S&T Turunen Oy | Transport & logistics | 2023 |
| Kuljetus Vänninen Oy | Transport & logistics | 2011 |
| Kuljetus Welin Oy | Transport & logistics | 1985 |
| Kuljetus ja Romunkeräys Voutilainen Oy | Water & waste | 2018 |
| Kuljetus&Logistiikka Eklind Oy | Transport & logistics | 2024 |
| Kuljetus-Lipponen ky | Transport & logistics | 1987 |
| Kuljetusliike Mähönen Oy | Transport & logistics | 1977 |
| Kuljetusliike S. Kervinen Oy | Transport & logistics | 1995 |
| Kuljetusliike Seppo Mustonen Oy | Transport & logistics | 2002 |
| Kuljetusliike Veljet Laitinen Oy | Transport & logistics | 1973 |
| Kunnon Kyökki Oy | Hospitality | 2010 |
| Kuokkalan vesiosuuskunta | Water & waste | 1996 |
| Kuopion Kuljetus Oy | Transport & logistics | 2018 |
| Kuormaus ja Kuljetus Seppo Holopainen Oy | Transport & logistics | 1990 |
| Kurko Academy Oy Ltd | Education | 2020 |
| Kurko Crane Oy Ltd | Manufacturing | 2018 |
| Kurko Projects Oy | Manufacturing | 2022 |
| Kurko-Koponen Oy | Construction | 2006 |
| Kuu Pizzeria Hamburger Oy | Hospitality | 2021 |
| Kuvaria Oy | Wholesale & retail | 2023 |
| Kvalimax Oy | Professional & scientific | 1990 |
| Ky Mika Rahkonen | Agriculture & fishing | 2019 |
| Kylppäri Suomi Oy | Construction | 2024 |
| Kymppikone Oy | Other services | 2021 |
| Kymppitaimi Kommandiittiyhtiö | Wholesale & retail | 2000 |
| Käpykankaan Autotalo Oy | Real estate | 2002 |
| Könönpellon Krouvi Ky | Hospitality | 1990 |
| LE Consulting Oy | Real estate | 2023 |
| Liuskat OY | Administrative & support | 2026 |
| LM Digital Projects Oy | Education | 2025 |
| LP Insrak Leo Oy | Construction | 1990 |
| LSK Granit Ky | Construction | 1998 |
| LVI Lepek OY | Construction | 2016 |
| LVI-Huolto Suihkonen Ky | Construction | 2006 |
| LVI-Palvelu Udd Oy | Construction | 2021 |
| LVI-Tekniikka Rissanen Oy | Construction | 2004 |
| LaMi Print Oy | Manufacturing | 2022 |
| Laatutaito Pirjo Janhunen Oy | Professional & scientific | 1993 |
| Laivalinna cruises oy | Transport & logistics | 2021 |
| LakelandSoft Oy | Information & communication | 2019 |
| LakiMajakka Oy | Professional & scientific | 2014 |
| Lakiasiaintoimisto Proleton Oy | Professional & scientific | 2024 |
| Lauran Puoti Oy | Wholesale & retail | 1968 |
| Led Future Oy | Manufacturing | 2017 |
| Lehtoniemen Automaalaamo Ky | Other services | 1982 |
| Lehtoniemen Metalli Oy | Manufacturing | 1983 |
| Leijonapesut Oy | Other services | 1997 |
| Leko-Talli Oy | Agriculture & fishing | 2011 |
| LempiMurre Oy | Wholesale & retail | 2023 |
| Lepco Rakennus Ky | Construction | 2006 |
| Lifebu Oy | Wholesale & retail | 2020 |
| Liikuntakeskus Kunnonsali Oy | Arts & recreation | 1999 |
| Liinaten Oy | Professional & scientific | 2019 |
| Lippen Oy | Health & social care | 2002 |
| Lissee Löylyä Oy | Other services | 2026 |
| Logistik Server Oy | Transport & logistics | 2010 |
| Lomalinna Oy | Real estate | 2008 |
| Loposen Linjat Ky | Transport & logistics | 2013 |
| Lutz Skate Oy | Wholesale & retail | 2023 |
| Lymfaterapia Jamo Oy | Health & social care | 2016 |
| Lääkintävoimistelu Jukka Reijonen Oy | Health & social care | 1987 |
| M & M Könönen Oy | Transport & logistics | 1980 |
| M Prittinen Ky | Wholesale & retail | 1991 |
| M&M sepät Oy | Real estate | 2023 |
| M.R. KAROBAR Oy | Financial services | 2024 |
| MAKI Service Engineering Oy | Professional & scientific | 2015 |
| MHplan OY | Manufacturing | 2008 |
| MP-Kylmä Oy | Manufacturing | 2011 |
| MSI Group Oy | Manufacturing | 1975 |
| MT On The Road Oy | Administrative & support | 2008 |
| MTP-consulting Oy | Wholesale & retail | 2014 |
| MV-Investor Oy | Real estate | 2023 |
| MYxPress OY | Wholesale & retail | 2024 |
| Maansiirto Kilpeläinen Oy | Construction | 2004 |
| Madness Company oy | Financial services | 2025 |
| Mainos Forum Oy | Professional & scientific | 2010 |
| Mainostoimisto Avant Arthouse avoin yhtiö | Professional & scientific | 1996 |
| Mainostoimisto Luode Oy | Professional & scientific | 2010 |
| Markus Ojanen & K:nit Oy | Wholesale & retail | 1978 |
| Marseilia Oy | Wholesale & retail | 2024 |
| MarskIT Oy | Information & communication | 2026 |
| Masterservice, Varkaus Oy | Manufacturing | 1996 |
| Mastone Oy | Mining & quarrying | 2008 |
| MediFinnovations Oy | Wholesale & retail | 2015 |
| Megi Megi Oy | Wholesale & retail | 2017 |
| Mekaanisen Musiikin Museo Kempf Ky | Arts & recreation | 1987 |
| Menetti Oy | Administrative & support | 2009 |
| MetTek Ky | Manufacturing | 2011 |
| Metalmix Oy | Manufacturing | 1979 |
| Metsuripalvelu H. Miettinen Ky | Agriculture & fishing | 1999 |
| Metsäkoneurakointi Flink Oy | Agriculture & fishing | 1985 |
| Metsäpalvelu Natunen Oy | Agriculture & fishing | 2010 |