| Rantasalmen Tennis Oy | Arts & recreation | 1982 |
| Rantasalon Metsät Avoin Yhtiö | Agriculture & fishing | 2017 |
| Rauta-Maatalous Jorma Koivisto Ky | Real estate | 1987 |
| Relanole Oy | Professional & scientific | 2025 |
| Rinssi-Eversti Oy | Hospitality | 2007 |
| Ruuvisenjoen Metsä Oy | Agriculture & fishing | 1995 |
| SCEL Palvelut Oy | Water & waste | 2016 |
| SK-Laskutus Oy | Other services | 2023 |
| SL-Tuote oy | Wholesale & retail | 2019 |
| SS Kurki Oy | Transport & logistics | 2023 |
| Saimaa Financial Consulting Oy | Administrative & support | 2022 |
| Saimaa Luxury Oy | Hospitality | 2018 |
| Saimaa Restaurants Oy | Hospitality | 2025 |
| Saimaa Treehouse Oy | Hospitality | 2019 |
| Saimaa Wellness Hotel Oy | Hospitality | 2021 |
| Saimaan Eräelämys Oy | Administrative & support | 1986 |
| Saimaan Erämajat Oy | Hospitality | 1986 |
| Saimaan Vesi ja Viemäri Oy | Water & waste | 2020 |
| Saimaantie Fishing Lodges Oy | Hospitality | 2020 |
| Saksansillan Kalaosuuskunta | Agriculture & fishing | 1998 |
| Sami Koskimaa Oy | Wholesale & retail | 1989 |
| Savo-Karjalan Huoltopalvelut Oy | Administrative & support | 2020 |
| Savon Siivous- ja Työapu Oy | Administrative & support | 2016 |
| Savon Sisustus & Maalitarvike Oy | Wholesale & retail | 2012 |
| Savorak Oy | Construction | 2008 |
| Sawon laaturakenne Oy | Construction | 2021 |
| Sora- ja Kuljetusliike Pulkkinen Oy | Transport & logistics | 1983 |
| SuurSavohalli Oy | Arts & recreation | 2000 |
| T & T Innocard Ky | Manufacturing | 2009 |
| Tpo Kammonen OY | Administrative & support | 2020 |
| TTT-Service Oy | Other services | 2015 |
| Tammentilit Oy | Professional & scientific | 2024 |
| Tar-Kat Oy | Administrative & support | 2018 |
| Taxi Pasi Issakainen Oy | Transport & logistics | 2021 |
| Tervajoen Vesiosuuskunta | Water & waste | 2004 |
| Tornioniemen vesiosuuskunta | Water & waste | 1994 |
| Tuomitaipale Oy | Agriculture & fishing | 2019 |
| Urakointi Huupponen Oy | Construction | 2008 |
| Uutistuotanto Finfoto Oy | Information & communication | 2011 |
| Vendace Ky | Agriculture & fishing | 1994 |
| Vihavaisen Taksi Oy | Transport & logistics | 2013 |
| Wolfun Ky | Professional & scientific | 2009 |