| Rakennus Timo Pekka Oy | Construction | 1987 |
| Rakennus ja Huolto M.Virolainen Oy | Administrative & support | 2018 |
| Rakennusliike MSJ-Rakennus Oy | Construction | 1995 |
| Rakennuspalvelu Ahonen Ky | Construction | 2016 |
| Rakennussaneeraus K. Hietala Oy | Construction | 1999 |
| Rakennusvalmiste Oy Forssa | Construction | 2010 |
| Rakentajat R & M Oy | Construction | 2007 |
| Ramex OY | Transport & logistics | 2024 |
| Ranpak BV Finland Branch | Professional & scientific | 2023 |
| Ratako Oy | Professional & scientific | 2012 |
| Ratinan Tili Oy | Professional & scientific | 1995 |
| Ravalla Oy | Construction | 2004 |
| Ravintola Anniina Oy | Real estate | 1997 |
| Ravintola Forssan Kultajyvä Ky | Hospitality | 2007 |
| Ravintola MeriPihka Oy | Hospitality | 2025 |
| Ravintola Tuulia Ky | Hospitality | 1982 |
| RePro Oy Hevospraktiikka | Professional & scientific | 2021 |
| Recolan Oy | Agriculture & fishing | 2023 |
| Rentbox Oy | Real estate | 2020 |
| Revoomm Oy | Wholesale & retail | 2021 |
| RiSaKa Kiinteistöt Oy | Real estate | 1993 |
| Riihicon Oy | Professional & scientific | 2024 |
| Riihivalkaman Kuljetus Oy | Construction | 2020 |
| Riipilän Uusimäki Oy | Real estate | 1964 |
| Rimpin Rakentajat Oy | Construction | 2011 |
| Roidon Rouvat Oy | Hospitality | 2020 |
| Royal kahvila Oy | Hospitality | 2023 |
| Rta Point oy | Construction | 1995 |
| Rvest Oy | Financial services | 2010 |
| SA-Hallinto Oy | Real estate | 1986 |
| SA-Yhtiöt Oy | Construction | 1989 |
| Saaren Tikku Ky | Hospitality | 2018 |
| SAME Works | Wholesale & retail | 2025 |
| SHA Partners Oy | Wholesale & retail | 2026 |
| Shudian OY | Real estate | 2003 |
| SK Customs & Paint Oy | Other services | 2025 |
| SPPH Invest Oy | Financial services | 2025 |
| SR Golf Oy | Arts & recreation | 2026 |
| SVMR Konsultointi Oy | Administrative & support | 2020 |
| Safiiri talli Oy | Agriculture & fishing | 2023 |
| Sagassa Oy | Real estate | 1990 |
| Sairaanhoitaja Satu Oy | Health & social care | 2025 |
| Salamaseppä Oy | Professional & scientific | 2023 |
| Salko Kiinteistöt Oy | Real estate | 2022 |
| Salko Painting Oy | Construction | 2014 |
| Salomet Oy | Manufacturing | 1986 |
| Saltia Oy | Professional & scientific | 1997 |
| Samperin Puusilmä Oy | Real estate | 2023 |
| Saneeraus Romppainen Oy | Construction | 2021 |
| Sapluuna Oy | Wholesale & retail | 1989 |
| Sarasmäen Kukka- ja Hautaustoimisto Ky | Other services | 1987 |
| Sari Kares Oy | Administrative & support | 2023 |
| Sateba Finland Oy | Manufacturing | 2012 |
| SeMix Palvelut avoin yhtiö | Wholesale & retail | 2022 |
| Serifors Ky | Manufacturing | 1991 |
| Shijie Oy | Hospitality | 2011 |
| Siivousapu ArjaMari Oy | Administrative & support | 2010 |
| Siivouspalvelu Forssan Ilona Oy | Administrative & support | 2005 |
| Siivoustukku Silläsiisti Oy | Wholesale & retail | 1996 |
| Sijoitusyhtiö VeTe Oy | Real estate | 2021 |
| Sik Sak verho & sisustus Ky | Wholesale & retail | 2007 |
| Sispro Oy | Real estate | 1992 |
| Sisu Coolers Oy | Real estate | 1999 |
| Skilvi Oy | Professional & scientific | 1988 |
| Skycat Oy | Professional & scientific | 2015 |
| SolFox Oy | Wholesale & retail | 2018 |
| Solarius Intellectual Properties Ky | Financial services | 2021 |
| Solarius Investments Oy | Financial services | 2020 |
| Sortohaan Teollisuuskiinteistöt Oy | Real estate | 2006 |
| Spina Ky | Professional & scientific | 2012 |
| Splenden Oy | Hospitality | 1995 |
| Sport Gate Oy | Wholesale & retail | 2008 |
| Sportti-Sakke Virtanen ja Korhonen | Wholesale & retail | 1989 |
| Stabic Ky | Manufacturing | 1994 |
| Stallo Oy | Wholesale & retail | 2021 |
| Stormtale Creations Oy | Information & communication | 2016 |
| Strike Lanes Bowling Oy | Arts & recreation | 2019 |
| Studio Inga Moisio Oy | Professional & scientific | 2021 |
| Suomen Erityisjäte Oy | Water & waste | 2004 |
| Suomen Kerroslevy Oy | Manufacturing | 2019 |
| Suomen Materiaalikierrätys Oy | Water & waste | 1989 |
| Suomen Mediatukku Oy | Wholesale & retail | 2018 |
| Suomen Sijoituspalvelu Oy | Financial services | 2021 |
| Suomen Tietoturva Oy | Professional & scientific | 2007 |
| Suomen purku & kierrätys Oy | Transport & logistics | 2024 |
| Super Mikael Oy | Professional & scientific | 2021 |
| Svanis Oy | Wholesale & retail | 2016 |
| Systeemisiskot Ky | Other services | 2015 |
| Sähkö-Säe Oy | Construction | 1968 |
| Sähköasennus Grönholm Oy | Construction | 2019 |
| Sähköasennus J-P Gröndahl Oy | Professional & scientific | 2009 |
| Sähköasennus Kuusisto Oy | Construction | 2019 |
| Sähköasennus Timo Jaakkola Oy | Construction | 2004 |
| Sähkömatti Oy | Construction | 2023 |
| Sähköpalvelu Petri Hintsanen Oy | Construction | 2016 |
| Sähkösuunnittelutoimisto Heimo Ojala Oy | Professional & scientific | 1998 |
| Särmä Art Oy | Construction | 2014 |
| Sääneuvos Oy | Information & communication | 2020 |
| TA-Rengas Ky | Wholesale & retail | 1999 |
| TKA-Kuljetus Oy | Transport & logistics | 2024 |