| Raso Eiendom AS | Real estate | 2004 |
| Raso Energi AS | Transport & logistics | 2001 |
| Rause AS | Health & social care | 1990 |
| Raymonds Diner AS | Hospitality | 2018 |
| RBS Eiendom AS | Real estate | 2008 |
| Renholder Sandra AS | Administrative & support | 2025 |
| Retro Rakkestad AS | Wholesale & retail | 2017 |
| RH Samdrift Da | Agriculture & fishing | 2004 |
| Ringgata 8 Rakkestad AS | Real estate | 2025 |
| Ringnes Motorsport AS | Other services | 2023 |
| Ringsby Gartneri AS | Agriculture & fishing | 2015 |
| Ringstad Gårdselskap AS | Real estate | 2005 |
| Rodrigues & Principe AS | Health & social care | 2020 |
| Rognerud Invest AS | Real estate | 2012 |
| Romerike Oppussing AS | Construction | 2017 |
| Rosenborgveien 12 AS | Real estate | 2021 |
| Rosenborgveien 7 Og 9 AS | Real estate | 2005 |
| Rosenborgveien 8 AS | Real estate | 2019 |
| RTB Invest AS | Construction | 2018 |
| Rudskogen Biogass AS | Energy | 2023 |
| Rudskogen Deponi AS | Water & waste | 2021 |
| Rudskogen Motorsenter AS | Arts & recreation | 1997 |
| Rudskogen Pitstopp AS | Wholesale & retail | 2017 |
| Rudskogen Tomt 1 AS | Real estate | 2019 |
| Rudskogen Tomt 2 AS | Real estate | 2019 |
| Rudskogen Tomt 3 AS | Real estate | 2019 |
| Rudskogen Tomter 2 AS | Real estate | 2018 |
| Rudskogen Tomter 3 AS | Real estate | 2018 |
| Rudskogen Tomter 4 AS | Real estate | 2018 |
| Rudskogen Tomter 5 AS | Real estate | 2018 |
| Rudskogen Tomter 6 AS | Real estate | 2018 |
| Rudskogen Tomter 7 AS | Real estate | 2018 |
| Rudskogen Tomter 8 AS | Real estate | 2020 |
| Rudskogen Tomter AS | Real estate | 2018 |
| Rudskogen Tomteselskap Holding AS | Real estate | 2018 |
| Rudskogenveien 86 AS | Real estate | 2021 |
| Ruud Eiendom AS | Real estate | 1994 |
| Ruvi AS | Energy | 2019 |
| Rxta Holding AS | | 2026 |
| Rådhusveien Helseteam AS | Real estate | 2004 |
| Rørtec AS | Construction | 1985 |
| S.B.S. Capital Management AS | Wholesale & retail | 2018 |
| S.E. Løken AS | Construction | 2014 |
| S.Skaug Invest AS | | 2026 |
| SA2 Media AS | Professional & scientific | 2021 |
| Sagveien 17 Rakkestad AS | Real estate | 2018 |
| Sander Løvland AS | Education | 2026 |
| Sander Løvland Holding AS | | 2025 |
| Sbi Eiendom AS | Real estate | 2012 |
| Sea Eagle AS | Professional & scientific | 2020 |
| Secton AS | Information & communication | 2026 |
| Seljedahl AS | Real estate | 2025 |
| Sember AS | Wholesale & retail | 2022 |
| Sember Holding AS | Wholesale & retail | 2016 |
| Sentrum Data AS | Information & communication | 2005 |
| Sentrum Skadedyrkontroll AS | Administrative & support | 2023 |
| September Invest AS | Financial services | 2005 |
| Ship-It Spedisjon AS | Transport & logistics | 2020 |
| Sibo Eiendom AS | Real estate | 2000 |
| Sida Gårdsdrift AS | Real estate | 1996 |
| Sigurd Slåttland Holding AS | Real estate | 2016 |
| Simen Emberland Holding AS | Manufacturing | 2016 |
| Sinnatreneren AS | Education | 2022 |
| Sjur Dahl Armering AS | Construction | 1999 |
| Skattebøl Da | Mining & quarrying | 2020 |
| Skjørten Massemottak AS | Water & waste | 2015 |
| Skogsbilveglaget Frøneveien SA | Real estate | 1956 |
| SL Eiendom Og Invest AS | Real estate | 2007 |
| SL Holding. AS | | 2025 |
| Slommerud Landbruk Da | Agriculture & fishing | 2011 |
| Slåttland Alpha Joint Stock Company AS | Professional & scientific | 2020 |
| Slåttland Eiendom AS | Real estate | 2021 |
| Slåttland Group AS | Manufacturing | 2019 |
| Slåttland Mek Industri AS | Manufacturing | 2016 |
| Slåttland Technology AS | Professional & scientific | 2016 |
| SMK Service AS | Other services | 2024 |
| Solishus AS | Wholesale & retail | 2021 |
| Soulsprings AS | Real estate | 2024 |
| Spilde Mek Verksted AS | Manufacturing | 1974 |
| Stallen Pizzapub AS | Hospitality | 2013 |
| Standard Forvaltning AS | Financial services | 1996 |
| Steinar Levernes AS | Construction | 1993 |
| Stonkeykongs & Comrades AS | | 2020 |
| Storgata 17 Rakkestad AS | Real estate | 2025 |
| Storgata 32 AS | Real estate | 2022 |
| Storgata 5 Rakkestad AS | Real estate | 2022 |
| Stubberud Anlegg AS | Construction | 2015 |
| Stubberud Holdingselskap AS | Construction | 2006 |
| Styreguiden AS | Professional & scientific | 2005 |
| Sunstad AS | | 2023 |
| Sushi-Teria Aln AS | Hospitality | 2025 |
| Svegra Holding AS | Financial services | 2017 |
| Sverstad Holding AS | | 2021 |
| Sydaksen Eiendom AS | Real estate | 2023 |
| Syknappen Da | Wholesale & retail | 2014 |
| T-T Custom Consult AS | Professional & scientific | 2018 |
| Ta Takservice AS | Construction | 2025 |
| Tangen Trafikkskole AS | Education | 2016 |
| Tannlege Igland AS | Health & social care | 2025 |
| Tar Invest AS | Real estate | 2005 |