| Sortland Butikkeiendom AS | Real estate | 2010 |
| Sortland Handelseiendom AS | Real estate | 2015 |
| Spanjor Invest AS | Financial services | 2016 |
| Sparebank 1 Ringerike Hadeland | Financial services | 1833 |
| Sparebank 1 Økonomihuset AS | Professional & scientific | 1997 |
| Sparehuset Hønefoss AS | Wholesale & retail | 2003 |
| Sparmax AS | Wholesale & retail | 2008 |
| Sparmax Eiendom AS | Real estate | 2007 |
| Sparmax Holding AS | Real estate | 2009 |
| Spenncon AS | Manufacturing | 1987 |
| Speti AS | Hospitality | 2022 |
| Spijker AS | Professional & scientific | 2016 |
| Spina Fysioterapi Og Manuellterapi Ringerike Da | Health & social care | 2005 |
| Spina Helse AS | Health & social care | 2025 |
| Spir Eiendom AS | Real estate | 2008 |
| Sponsor Compagniet AS | Administrative & support | 2006 |
| Sport 1 Kuben AS | Wholesale & retail | 2023 |
| Sprengfjell AS | Construction | 2021 |
| ST Interiør AS | Wholesale & retail | 2014 |
| ST Olavs Gate Terrasse AS | Real estate | 2022 |
| ST. Olav Invest AS | Real estate | 2008 |
| ST. Olavsgate 7 & 9 AS | Real estate | 2014 |
| Stabells Gate 8 AS | Real estate | 2003 |
| Stabellsg 13 Hønefoss Ans | | 1989 |
| Stadheim Invest AS | Real estate | 2023 |
| Stall Bergsund AS | Education | 2005 |
| Stall Grini AS | Agriculture & fishing | 1999 |
| Stall Malmin AS | Education | 2022 |
| Stamsetra Holding AS | Real estate | 2021 |
| Stang Invest AS | Health & social care | 1992 |
| Stange Industri AS | Mining & quarrying | 2009 |
| Stasjonsdrift Elviken AS | Wholesale & retail | 2021 |
| Stavern Butikkeiendom AS | Real estate | 2005 |
| STB 5-201 Og 5-502 AS | Real estate | 2019 |
| Steellogic AS | Manufacturing | 2025 |
| Steine Prosjekt AS | Professional & scientific | 2016 |
| Steinkjer Handelsbygg AS | Real estate | 2011 |
| Steinkjer Nord Handelspark AS | Real estate | 2014 |
| Steinsfjorden Montessoriskole SA | Education | 2009 |
| Stenbro AS | Professional & scientific | 2005 |
| Stenor Holding AS | | 2005 |
| Stians Bilglass AS | Other services | 2015 |
| Stjerne Regnskap AS | Professional & scientific | 2019 |
| Stjernegrisen AS | | 2025 |
| Stokkamyrveien Handelsbygg AS | Real estate | 2008 |
| Stokmarknes Handelseiendom AS | Real estate | 2018 |
| Stord Grossistbygg AS | Real estate | 2019 |
| Stord Handelsbygg AS | Real estate | 2018 |
| Storeglum Finans AS | Financial services | 2005 |
| Storelva Arkitekter AS | Professional & scientific | 2024 |
| Storg 21 AS | Real estate | 1963 |
| Storgata 4 Hønefoss AS | Real estate | 2022 |
| Storgata Notodden AS | Real estate | 2014 |
| Storgaten 20 a Og B AS | Real estate | 2013 |
| Storgaten 26 Hønefoss AS | Real estate | 2007 |
| Storgaten 6 Hønefoss AS | Real estate | 2023 |
| Storgaten 76-78 Lillehammer AS | Real estate | 1998 |
| Storgaten Bil AS | Other services | 1989 |
| Stormester AS | Arts & recreation | 2014 |
| Storskogen Musikk AS | Information & communication | 2023 |
| Stranden Skole Eiendom AS | Real estate | 2015 |
| Strix Eiendom AS | Real estate | 2005 |
| Strøm Drift AS | Administrative & support | 2025 |
| Strømmen Bilformidling AS | Wholesale & retail | 2008 |
| Strømmen Butikkeiendom AS | Real estate | 2005 |
| Stua Fjeld AS | Wholesale & retail | 2003 |
| Studio 3 Hårverksted Ans | Other services | 1982 |
| Studio Fønix AS | Other services | 1997 |
| Studio Skogheim AS | Other services | 2016 |
| Styrkestua AS | Education | 2023 |
| Stærkebye AS | | 2018 |
| STØA'S IMPORT ANS Liv Marit og Per Oskar Støa | Wholesale & retail | 1988 |
| Støyten Trafikkskolesenter AS | Education | 2009 |
| Sukken Begravelsesbyrå AS | Other services | 1981 |
| Sulland Ringerike AS | Other services | 1986 |
| Sun AS | Real estate | 2012 |
| Sundgata 10A AS | Real estate | 2020 |
| Sundland Eiendomsselskap AS | Real estate | 2018 |
| Sundvollen Butikkeiendom AS | Real estate | 2014 |
| Sundvollen Infrastruktur AS | Real estate | 2022 |
| Sundvollen Sentrum AS | Real estate | 2022 |
| Sunn Helse Og Figurforming AS | Health & social care | 2012 |
| Superflaks AS | Arts & recreation | 2017 |
| Svartplassen AS | Real estate | 2005 |
| Sveaborg Handel AS | Wholesale & retail | 1984 |
| Svein G. Sætheren Da | Transport & logistics | 2007 |
| Svein Svendsen Trafikkskole Hønefoss AS | Education | 2014 |
| Svein Søyland AS | Arts & recreation | 2002 |
| Sverre Haugli Bilforretning AS | Wholesale & retail | 1973 |
| Svillegjenvinning AS | Water & waste | 2018 |
| Svolvær Butikkeiendom AS | Real estate | 2010 |
| SVS Holding AS | Financial services | 2005 |
| Sweats AS | Wholesale & retail | 2018 |
| Sweet Spot Hønefoss AS | Hospitality | 2026 |
| Swiss Helikopter Norway AS | Wholesale & retail | 2018 |
| Sy Og Strikkebutikken AS | Wholesale & retail | 2006 |
| Sytan AS | Health & social care | 2006 |
| Syvende Far AS | Manufacturing | 2023 |
| Sæterlid 3D Service AS | Professional & scientific | 2017 |
| Sætheren Eiendom AS | Real estate | 2000 |