| Auto Luola Oy | Wholesale & retail | 1998 |
| Auto-Kuhanen Ky | Transport & logistics | 1987 |
| Autolato Oy | Wholesale & retail | 2025 |
| Autopalvelu T. Virtanen Oy | Other services | 2020 |
| Diablo Nutrition Oy | Wholesale & retail | 2025 |
| Dream Pets Oy | Wholesale & retail | 2020 |
| Gyllentek Oy | Real estate | 1995 |
| HSL Group Oy | Wholesale & retail | 2017 |
| Heinolan Kauppahallit Oy | Wholesale & retail | 2018 |
| Heinolan Teollisuushuolto oy | Manufacturing | 2022 |
| Helmi ja Hugo Oy | Hospitality | 2018 |
| HiTechHouse Oy | Wholesale & retail | 2020 |
| Hietalan Sora ja Sepeli Oy | Public administration | 2022 |
| HomeCare NP Oy | Health & social care | 2025 |
| Janipa Invest Oy | Real estate | 2026 |
| Kiinteistö Oy Heinolan Myllypelto | Real estate | 1991 |
| Kiinteistö Oy Levi-Haukka | Real estate | 1989 |
| Kiinteistö Oy Maitiaislahti | Real estate | 1991 |
| Kiinteistö Oy Punapihlaja | Real estate | 1991 |
| Kuitulinja Oy | Wholesale & retail | 1978 |
| Kuljetus Lahtio & Nihtilä Oy | Transport & logistics | 2016 |
| LVI-Eristys Pulkkinen Oy | Construction | 2021 |
| Liivat RL Oy | Manufacturing | 2024 |
| MPuu Oy | Agriculture & fishing | 2022 |
| Mattelo Oy Ltd | Administrative & support | 2021 |
| Mittakanava Oy | Manufacturing | 2009 |
| Multistar Oy | Real estate | 1994 |
| Myllyoja Dressage Oy | Arts & recreation | 2025 |
| Myllyojan Kauppahallit Oy | Wholesale & retail | 2025 |
| Nahe Oy | Wholesale & retail | 1992 |
| Nykykoti Oy | Wholesale & retail | 1983 |
| Ourmind Oy | Information & communication | 2018 |
| Oy Pitopalvelu Punaherukka | Hospitality | 2022 |
| Oy Tightlock Ltd | Manufacturing | 1977 |
| Putkityö Helmi Oy | Construction | 2023 |
| Putkiurakointi Simpanen Oy | Construction | 1989 |
| RakeNord Oy | Construction | 2026 |
| Rakennus ja Saneeraus Mustonen Oy | Construction | 1989 |
| Rakennustyö Nyman Oy | Construction | 2017 |
| Rauh & Mau Oy | Wholesale & retail | 2020 |
| Rotia Oy | Agriculture & fishing | 2010 |
| Rustic Charm Ky | Wholesale & retail | 2000 |
| Sawico Oy | Wholesale & retail | 2025 |
| Soukarankärki Oy | Energy | 2022 |
| Sähkö-Saarnikannas Oy | Construction | 1989 |
| T-Work Oy | Construction | 2022 |
| TPK Capital oy | Manufacturing | 2024 |
| Tamivest Oy | Financial services | 2026 |
| Tencity Oy | Transport & logistics | 1995 |
| Tenlos Oy | Real estate | 1998 |
| Tim-Elec Oy | Professional & scientific | 2018 |
| TuuliPro Oy | Professional & scientific | 2012 |
| Vital Nature Oy | Wholesale & retail | 2018 |
| WLM Holding Oy | Financial services | 2012 |