| KJN-Yhtiöt Oy | Real estate | 1982 |
| KL-Steel Oy | Manufacturing | 2018 |
| Kohdiste OY | Professional & scientific | 2010 |
| KOS saari Oy | Other services | 2020 |
| KOY Hämeenlinnan Konepajantie 9 | Real estate | 2012 |
| KOY Hämeenlinnan Takumäenkuja 2 B | Real estate | 2019 |
| KOy Rastihallit | Administrative & support | 2013 |
| KS-Yhtymä Oy | Arts & recreation | 2011 |
| KT Metsä Oy | Agriculture & fishing | 2019 |
| KTS-Invest Oy | Professional & scientific | 1994 |
| KTV-Palvelut Huhtala Oy | Arts & recreation | 2024 |
| KUTUN Ecosystems Finland Oy | Professional & scientific | 2025 |
| KY Siivouspalvelut Oy | Administrative & support | 2012 |
| Kaarle Kokko Oy | Hospitality | 2021 |
| Kabul Kitchen Oy | Hospitality | 2018 |
| Kahvihammas Oy | Health & social care | 2015 |
| Kahvikivi Oy | Professional & scientific | 2018 |
| Kahvila-Puoti Justiinan Tupa Oy | Hospitality | 2026 |
| Kaihdin-Pete Oy | Construction | 2021 |
| Kaislapojat Oy | Construction | 2023 |
| Kalevala Media Oy | Professional & scientific | 2013 |
| Kallioinen Oy | Wholesale & retail | 1979 |
| Kaloisenrannan Laituri Oy | Real estate | 1992 |
| Kalpala Oy | Administrative & support | 2021 |
| Kalz Palvelut Oy | Other services | 2020 |
| Kamux Oyj | Financial services | 2011 |
| Kamux Suomi Oy | Wholesale & retail | 2000 |
| Kangasluoma Invest Oy | Professional & scientific | 2025 |
| Kankaantaan Lämpö Oy | Energy | 1972 |
| Kanta-Hämeen Aluetaksi Oy | Transport & logistics | 1993 |
| Kanta-Hämeen Asuntomyynti Ky | Real estate | 1985 |
| Kanta-Hämeen Eläinklinikka Oy | Professional & scientific | 2022 |
| Kanta-Hämeen Jakelu Oy | Transport & logistics | 2010 |
| Kanta-Hämeen Kiinteistöala Oy | Construction | 1990 |
| Kanta-Hämeen Kuljetus Oy | Transport & logistics | 2014 |
| Kanta-Hämeen Rahti Oy | Transport & logistics | 2017 |
| Kanta-Hämeen Sammutinhuolto Oy | Manufacturing | 1976 |
| Kanta-Hämeen Tehorakennus Oy | Construction | 1992 |
| Kanta-Hämeen Teollisuuskiinteistöt Oy | Real estate | 2007 |
| Kanta-Hämeen Tilaihme Oy | Real estate | 2008 |
| Kanta-Hämeen Tuoretuote Oy | Wholesale & retail | 2009 |
| Kanta-Pakkaus Oy | Wholesale & retail | 1989 |
| Kantamedia Oy | Information & communication | 2014 |
| Kantaputki Oy | Construction | 1994 |
| Kantayhtymä Oy | Professional & scientific | 2008 |
| Kantola Padel ja Sulka Oy | Arts & recreation | 2023 |
| Kantolan Auto ja MP Huolto avoin yhtiö | Other services | 2006 |
| Kantolan Kahvilat Oy | Hospitality | 2008 |
| Kantolan Kellari Oy | Wholesale & retail | 2020 |
| Kantolan Kortti Tuote Oy | Wholesale & retail | 1997 |
| Kantolan Kultaportti Oy | Financial services | 1994 |
| Kantolan Lounas-Ravintola Myllytupa Oy | Hospitality | 2004 |
| Kantolan Majakka Oy | Real estate | 2002 |
| Kanttura Oy | Manufacturing | 2013 |
| Kapiten Oy | Professional & scientific | 2018 |
| Kappola Invest Oy | Real estate | 1974 |
| Kargo Oy | Information & communication | 2021 |
| Karhunkyyti Oy | Education | 2018 |
| Kari Saari Oy | Professional & scientific | 1986 |
| Karimo Oy | Transport & logistics | 2015 |
| KasCap Oy | Professional & scientific | 2018 |
| Kasevalta Oy | Professional & scientific | 2020 |
| Kassa- ja Toimistohuolto Häme Oy | Other services | 1976 |
| Kastarin Kehitys Oy | Health & social care | 2017 |
| Kasvua Oy | Manufacturing | 2013 |
| Kasvusi Oy | Professional & scientific | 2024 |
| Kataja Healthcare Oy | Health & social care | 2017 |
| Katepaja Oy | Professional & scientific | 1996 |
| Katinala AV Oy | Wholesale & retail | 2016 |
| Katinala Live Oy | Arts & recreation | 2017 |
| Katisten Ravintola Oy | Hospitality | 2022 |
| Katju Monipalvelut Oy | Administrative & support | 2023 |
| Katleena Kortesuo Oy | Professional & scientific | 2011 |
| Katriinakorut Oy | Wholesale & retail | 2007 |
| Katsastuskuvio Oy | Professional & scientific | 2012 |
| Kattomestarit Oy Rakennusliike | Construction | 2014 |
| KauneusTaika Oy | Other services | 2019 |
| Kauneushuone Valentina Oy | Other services | 2016 |
| Kauneuspaikka Peppi Ky | Construction | 2006 |
| Kauppahuone Somervuori Oy | Wholesale & retail | 2015 |
| Kaurialan Manu Oy | Wholesale & retail | 2001 |
| Kaurialan Tilipalvelu Oy | Professional & scientific | 2014 |
| Kaus-Kantolan Autokatsastus Oy | Professional & scientific | 2007 |
| Kehome Oy | Arts & recreation | 2020 |
| Keinusaaren kukkakioski Ky | Wholesale & retail | 2000 |
| Keittiö-Säe Oy | Construction | 2014 |
| Kellokeskus Laine Oy | Wholesale & retail | 1977 |
| Kellys cafe oy | Hospitality | 2021 |
| Kemikalioliike Olet Kaunis Oy | Wholesale & retail | 2015 |
| Kenetti Oy | Wholesale & retail | 2022 |
| Kenkä-Oscar Oy | Wholesale & retail | 1981 |
| Kepne-Consulting Oy | Professional & scientific | 1960 |
| Keravan Kuriirit Oy | Transport & logistics | 2014 |
| Kerhoravintola Seiska Oy | Hospitality | 1990 |
| Kerta Group Oy | Administrative & support | 2024 |
| Keski-Suomen Rakennus-Purku Oy | Construction | 2007 |
| Kesti Finance Oy | Financial services | 2021 |
| Keväthanki Management Oy | Professional & scientific | 2022 |
| Keys2Balance Oy | Professional & scientific | 2011 |
| Keysome Oy | Real estate | 2026 |