| Koite Oy | Construction | 2017 |
| Kone22 Oy | Construction | 2022 |
| Konsultointi Karppanen Oy | Administrative & support | 2023 |
| Koodikettu Oy | Information & communication | 2017 |
| Kormano Oy | Wholesale & retail | 1989 |
| Kuljetus J Gustafsson Oy | Transport & logistics | 2012 |
| Kuljetus J Lehtisuo Oy | Transport & logistics | 2012 |
| Kuljetus L & J Nieminen Oy | Transport & logistics | 1990 |
| Kuljetus N & M Oy | Transport & logistics | 1998 |
| Kuljetus ja Maanrakennus Reponen Oy | Construction | 2006 |
| Kuljetusliike Helokivi Oy | Transport & logistics | 1979 |
| Kuljetusliike Juhani Tuomi Oy | Transport & logistics | 1970 |
| Kylvö Capital Oy | Administrative & support | 2020 |
| Kymen Ekowatti Oy | Construction | 2020 |
| LTPLahti Oy | Administrative & support | 2019 |
| LVI-Talo 21 Oy | Construction | 2022 |
| LVI-suunnittelu PAM-energia Oy | Professional & scientific | 1981 |
| Lahden Autolämpö Oy | Other services | 2024 |
| Lahden Kiinteistötekniikka Oy | Real estate | 2018 |
| Lahden Laattatiimi Oy | Construction | 2020 |
| Lahden Minikonepalvelu Oy | Construction | 2015 |
| Lahden Mittaovi Oy | Manufacturing | 1985 |
| Lahden Ruokapalvelut Oy | Hospitality | 2016 |
| Lahden metsuri- ja sahauspalvelu Ky | Agriculture & fishing | 2015 |
| Lahinta Oy | Transport & logistics | 2018 |
| Lainalapio oy | Administrative & support | 2018 |
| Lakipalvelu Salmi Oy | Professional & scientific | 2022 |
| Lasmet Oy | Real estate | 1990 |
| Lehman, Enron & Madoff Capital Oy | Financial services | 2025 |
| Lepo Product Oy | Manufacturing | 1990 |
| Lieka Oy | Professional & scientific | 2018 |
| Likoniemi Oy | Professional & scientific | 2023 |
| Litulaukka Oy | Real estate | 2019 |
| Lumia Consulting Oy | Professional & scientific | 2024 |
| Luna Univer Finland Oy | Wholesale & retail | 2025 |
| M-Siivous Ky | Administrative & support | 2007 |
| M-Terprise Oy | Wholesale & retail | 1997 |
| MKM Sähkö Oy | Construction | 1992 |
| ML-Laite Ky | Construction | 2011 |
| MM Kate Oy | Financial services | 2013 |
| MO Pinta OY | Construction | 2016 |
| MaaMaNu Oy | Construction | 2025 |
| Maalaus & Rakennus Laukkanen Oy | Construction | 2010 |
| Maanrakennus Ilpo Kaija Ky | Construction | 1980 |
| Maanrakennus M&M Oy | Construction | 2013 |
| Mad Wave Europe Oy | Wholesale & retail | 2015 |
| Manatee Oy | Information & communication | 2016 |
| Mariluo Oy | Professional & scientific | 2021 |
| Markkinointiruutu Oy | Real estate | 2012 |
| Marktom Oy | Hospitality | 2009 |
| MatKaPe Ky | Wholesale & retail | 2021 |
| Mietos Oy | Information & communication | 2024 |
| Mikamika Oy | Information & communication | 2019 |
| Moreno Oy | Professional & scientific | 2021 |
| Mukana Tuotteet Oy | Manufacturing | 2018 |
| NDH Group Oy | Hospitality | 2026 |
| NP-Building Oy | Construction | 2010 |
| Nakari events Oy | Arts & recreation | 2024 |
| Napapiirin Hamppu Oy | Professional & scientific | 2019 |
| Nasto-Polar Rakennuspalvelut Oy | Construction | 2004 |
| Nastolan Ateriapalvelu Oy | Hospitality | 2025 |
| Nastolan Keskuskangas Oy | Real estate | 2003 |
| Nastolan LVI-ala Oy | Construction | 2008 |
| Nastolan Promet Oy | Manufacturing | 1994 |
| Nastolan Romu Oy | Wholesale & retail | 1995 |
| NetMinders Oy | Arts & recreation | 2015 |
| Neurokirurgit Pro Oy | Health & social care | 2022 |
| Niiniliina Oy | Professional & scientific | 2026 |
| Oivaoffset Ky | Manufacturing | 1988 |
| Oivatuote Oy | Construction | 2006 |
| Ottoman Trading Oy | Professional & scientific | 2004 |
| P & P Laihanen Oy | Construction | 1994 |
| Palvelut Aunola OY | Health & social care | 2011 |
| PJA-Kone Oy | Manufacturing | 1994 |
| PK-Mek KY | Manufacturing | 1988 |
| Paha Digital Oy | Professional & scientific | 2017 |
| Palvelutaksi Tolsa Oy | Transport & logistics | 2019 |
| Patama Logistics Oy | Transport & logistics | 2026 |
| Peikkometsän Liikuntapäiväkoti Villähde Oy | Education | 2019 |
| Perhekoti Pörriäinen Ky | Health & social care | 2006 |
| Perinnepaja Oy | Other services | 2024 |
| Pihasiistiksi Suomi Oy | Construction | 2021 |
| Pointtisi Oy | Manufacturing | 2019 |
| Potun Rengas ja Remontti Oy | Manufacturing | 1987 |
| PrimusNeliöt Oy | Real estate | 2023 |
| Pro Holding Group Oy | Financial services | 2025 |
| Pro Kaksikko Oy | Manufacturing | 2007 |
| Pro-pelli Ky | Construction | 2003 |
| ProWiz Oy | Professional & scientific | 2026 |
| Protia Oy | Real estate | 2007 |
| Pumpoint Oy | Wholesale & retail | 2021 |
| Päijänne Sähkö Oy | Construction | 2006 |
| Päijät Murske Oy | Mining & quarrying | 2020 |
| Päijät-Hämeen Huoltokeskus Oy | Other services | 1981 |
| Päijät-Hämeen Lokapalvelu Ky | Water & waste | 1991 |
| R-Kuljetus Oy | Transport & logistics | 2024 |
| R2 Design Oy | Professional & scientific | 2010 |
| Rakennusliike Oika OY | Construction | 2019 |
| RKM Kaikkonen Oy | Professional & scientific | 2020 |
| RPMV Invest Oy | Financial services | 2019 |