| Puu- ja Rakennustarvike Seppo Salminen Oy | Wholesale & retail | 1997 |
| Päivätoiminta Kipinä Oy | Health & social care | 2012 |
| Q3 Measuring Technology Oy | Manufacturing | 2020 |
| Quantum Accendo Ky | Professional & scientific | 1990 |
| R-Logistiikka Oy | Transport & logistics | 1983 |
| RH-SEMA Oy | Real estate | 1981 |
| RPR Works oy | Construction | 2025 |
| RTN Rakennus Oy | Construction | 1999 |
| Race Rebels Oy | Arts & recreation | 2020 |
| Rakennus-Rauhamäki Oy | Construction | 1993 |
| Rakennusliike Lahtinen Oy | Construction | 1987 |
| Rakennusliike S & L Tuominen Oy | Construction | 1987 |
| Rakennuspalvelu Jouni Nurminen Oy | Construction | 2018 |
| Rakennuspalvelu Muottilukko Oy | Construction | 1995 |
| Rakennustoimisto PPK Oy | Construction | 2009 |
| Rakennustyö Seppälä Oy | Construction | 2006 |
| Rakennustyö Suominen Oy | Construction | 2012 |
| Rakennusurakointi E. Salminen Oy | Construction | 1985 |
| Ravintola Pikis Oy | Hospitality | 2022 |
| Ravintola Rannikot Avoin yhtiö | Hospitality | 1993 |
| Reipas Asunnot Oy | Real estate | 2019 |
| Relive Oy | Real estate | 1986 |
| RepoRemontit Oy | Construction | 2025 |
| Retro-osa Oy | Wholesale & retail | 2023 |
| Rewolin Oy | Agriculture & fishing | 2024 |
| Risiko Oy | Real estate | 1994 |
| RouRak Oy | Construction | 2021 |
| Ruiskumassalattiat Suomi Oy | Construction | 2026 |
| Ruohon Taksit Oy | Transport & logistics | 2016 |
| Ruska Tuotanto Oy | Professional & scientific | 2019 |
| Ruusukivi Kiinteistöt Oy | Mining & quarrying | 2005 |
| Rynölä Oy | Real estate | 1990 |
| Röman Group Oy | Financial services | 2024 |
| S & L Turvapalvelut Oy | Administrative & support | 1996 |
| SATJAM Oy | Construction | 2012 |
| SFF-Racing Oy | Wholesale & retail | 2011 |
| SM Kiinteistötekniikka Oy | Construction | 2022 |
| ST Jämsä Oy | Construction | 2021 |
| Sadas Cheese Oy | Wholesale & retail | 2002 |
| Saferon Oy | Education | 2012 |
| Sajite Oy | Financial services | 1985 |
| Saliens Oy | Professional & scientific | 2017 |
| Salinmäki Oy | Arts & recreation | 2013 |
| Saloksi Oy | Construction | 2022 |
| Salon Studio Oy | Other services | 2021 |
| Salosen Vauhti Oy | Wholesale & retail | 2020 |
| Satapiikki Pro Oy | Manufacturing | 2007 |
| Science Evolution Oy | Health & social care | 2025 |
| Seppolan Auto Oy | Wholesale & retail | 1983 |
| Seppolan Kauppa Ky | Wholesale & retail | 2003 |
| Seppolan Konepalvelu Oy | Administrative & support | 2022 |
| Seppolan Sähkö Oy | Construction | 1990 |
| Seppälän Veneranta Oy | Transport & logistics | 1991 |
| Shipping Line Rainbow Oy | Administrative & support | 1998 |
| Simulaattorimaailma Oy | Arts & recreation | 2007 |
| Sisusauna Oy | Construction | 2015 |
| Sitemec Oy | Manufacturing | 2007 |
| Snow Fun Club Himos Oy | Financial services | 1992 |
| Socle Jämsä Oy | Construction | 1990 |
| Spinning Capital Oy | Professional & scientific | 2024 |
| Sport Heinonen Oy | Wholesale & retail | 1983 |
| Sports Lane Avoin yhtiö | Arts & recreation | 2005 |
| Success Factory Oy | Professional & scientific | 2003 |
| Suomen Kaupunkikoti Vuokraus Oy | Real estate | 2022 |
| Suomen Teollisuusautomaatio Oy | Construction | 1992 |
| Supertune Oy | Other services | 2021 |
| Suunnittelutoimisto Plaanari Oy | Professional & scientific | 1995 |
| Syysmyrsky Oy | Real estate | 2009 |
| Sähkö-Äijät Oy | Construction | 2025 |
| SähköMaisterit Oy | Construction | 2008 |
| Sähkömac Ky | Construction | 1999 |
| Sähkötyö Selänniemi Oy | Construction | 2022 |
| Säyrylän Lomat Oy | Administrative & support | 2025 |
| T-market Torinkulma Pekka Kiviaho Ky | Wholesale & retail | 1981 |
| TJ Markkanen Oy | Arts & recreation | 2011 |
| TJ Sähkötyö Ky | Construction | 2010 |
| TJH Tekniikkatalo Oy | Real estate | 2025 |
| TKA-TYÖ Oy | Other services | 2020 |
| TNN Invest Oy | Real estate | 2017 |
| TOP-Resort Oy | Hospitality | 2021 |
| Taksi Jämsä Oy | Transport & logistics | 1994 |
| Taksi Tapsa Jämsä Oy | Transport & logistics | 2016 |
| Taksi Äikäs Oy | Transport & logistics | 2023 |
| Talasmaja Oy | Hospitality | 2008 |
| Talastekniikka Oy | Construction | 2010 |
| Team Turkki Ky | Construction | 2003 |
| Temagroup Oy | Manufacturing | 2008 |
| Terho Parikka Ky | Manufacturing | 1985 |
| Terraviva Oy | Wholesale & retail | 1993 |
| Terästassu Oy | Manufacturing | 2017 |
| Tilausliikenne Vesa Karjalainen Oy | Transport & logistics | 1995 |
| Tili-Akka Oy | Professional & scientific | 1989 |
| Tilikorpela Oy | Professional & scientific | 2024 |
| Tilitalo Aaltonen Oy | Professional & scientific | 1998 |
| Tobermore Oy | Hospitality | 1995 |
| Toimintaterapia Taimi Oy | Health & social care | 2026 |
| TopicalBase Oy | Information & communication | 2024 |
| Traveller Viitala Oy | Administrative & support | 1999 |
| Tuomo Mäyrämäki Oy | Hospitality | 1995 |
| Työnohjaus Ajantaikaa Oy | Other services | 1995 |