| Sirikjerke Beitelag SA | Agriculture & fishing | 2015 |
| Sisfar AS | | 2005 |
| Sivilingeniør Terje Økland AS | Professional & scientific | 2021 |
| Sjøfront Eiendom AS | Real estate | 2011 |
| Sjønnegård AS | Transport & logistics | 2018 |
| Skandterm AS | Construction | 2019 |
| Skar Hot Rod Service AS | Wholesale & retail | 2026 |
| Skibrekk AS | Construction | 2015 |
| Skibrekk Holdco AS | | 2025 |
| Skibrekk Invest AS | | 2024 |
| SKJÆVES72 AS | | 2024 |
| Skogvarme Bioenergi AS | Energy | 2023 |
| Skyfix Nordic Nuf | Manufacturing | 2013 |
| Skyscout Europe AS | Professional & scientific | 2025 |
| SL Asfalt AS | Construction | 2025 |
| Sleipnir Holding AS | | 2023 |
| Slettbakkveien SA | Real estate | 2020 |
| Slette AS | Wholesale & retail | 2023 |
| Smalbo AS | Real estate | 2010 |
| Smart Trafikkopplæring AS | Education | 2011 |
| Solhellinga Holding AS | | 2020 |
| Solteam AS | Administrative & support | 2023 |
| Soro Invest AS | Real estate | 2001 |
| Sound Track Productions AS | Information & communication | 2012 |
| Sparebanken Øst | Financial services | 1970 |
| Spekebua AS | Wholesale & retail | 2011 |
| Spekebua Butikkdrift AS | Wholesale & retail | 2020 |
| Spekebua Firmagaver AS | Wholesale & retail | 2021 |
| Spekebua Nett Og Engros AS | Wholesale & retail | 2018 |
| Spike AS | Real estate | 2024 |
| Spillorama Hokksund AS | Arts & recreation | 2007 |
| Splitkon Entreprenør AS | Construction | 2024 |
| Spot-On AS | Other services | 2012 |
| Sprinkler Kongen AS | Construction | 2021 |
| Sprinkler Kongen Gruppen AS | Construction | 2026 |
| Spylevakta AS | Water & waste | 2017 |
| Spylevakta Avd Viken Øst AS | Water & waste | 2016 |
| Stall Horgen AS | Arts & recreation | 2000 |
| Stasjonsgata 10-12 Eiendom AS | Real estate | 2010 |
| Stasjonsgata 29 AS | Real estate | 2021 |
| Stasjonsgata 30 AS | Real estate | 2006 |
| Stasjonsgata 36 AS | Real estate | 2016 |
| Stasjonsgata 52-56 AS | Real estate | 2021 |
| Stasjonsgata 91 AS | Real estate | 2020 |
| Stasjonsgata Legekontor Da | Health & social care | 1998 |
| Stasjonsgaten 61 AS | Real estate | 2007 |
| Stasjonsveien 25-29 AS | Real estate | 2024 |
| Steinmontøren AS | Construction | 2005 |
| Stenshorne Eiendom AS | Real estate | 2021 |
| Step in Boutique AS | Wholesale & retail | 2024 |
| Stockshop AS | Wholesale & retail | 2024 |
| Storeulv Holding AS | Construction | 2021 |
| Storgata 33 Kongsberg AS | Real estate | 2025 |
| Storgata 51 AS | Real estate | 2008 |
| Storgt Drift AS | Wholesale & retail | 2024 |
| Storm Eg Eiendom AS | Real estate | 2018 |
| Strandhogg Invest AS | | 2023 |
| Støagata 14 AS | Real estate | 2015 |
| Støperigata 10 AS | Real estate | 2018 |
| Subsea Eiker AS | Real estate | 2012 |
| Subsea Maskinering AS | Manufacturing | 2008 |
| Subsea Topco AS | | 2025 |
| Sundemoen Fast Food Ans | Hospitality | 2000 |
| Sveaborg Invest AS | Real estate | 2022 |
| Svein Eide Autorisert Rørleggermester AS | Construction | 1993 |
| Svein Rust Eiendom AS | Real estate | 2012 |
| Svemo Holding AS | Construction | 2005 |
| Svemo V AS | Professional & scientific | 2021 |
| Sverre Isachsen Anlegg & Transport AS | Arts & recreation | 2004 |
| Svåsand Invest AS | Financial services | 2005 |
| Swami AS | Manufacturing | 2023 |
| Sy-Nett Symaskiner Salg Og Service AS | Wholesale & retail | 2018 |
| Systemglass AS | Construction | 2024 |
| Søderlind Holding AS | | 2020 |
| Søndre Vaalen Gård AS | Real estate | 2026 |
| Sørbye & Sønner AS | Construction | 2018 |
| T & I Norge AS | Construction | 2016 |
| T Grøstad Holding AS | | 2023 |
| Tak Systemer AS | Construction | 2016 |
| Tak- Partner AS | Construction | 2001 |
| Takpartner Holding AS | Construction | 2005 |
| Tangengata 2-4 Eiendom AS | Real estate | 2014 |
| Tannlege Ingunn Løkensgard AS | Health & social care | 2005 |
| Teask Holding AS | | 2024 |
| Teb Partner AS | | 2020 |
| Teddy AS | Wholesale & retail | 2016 |
| Tegleverksveien 71 AS | Real estate | 2014 |
| Temporent AB | Administrative & support | 2007 |
| Tepper & Gulvbelegg AS | Construction | 2022 |
| Terje Næss Eiendomstaksering AS | Professional & scientific | 2017 |
| Terrax AS | Construction | 2025 |
| Terrax Utleie AS | Administrative & support | 2026 |
| Tewle AS | | 2005 |
| TH. Liens Turistbusser A/S | Transport & logistics | 1988 |
| Thor Egil Stølen AS | Professional & scientific | 1996 |
| Tillibel Norway AS | Information & communication | 2020 |
| Tjenester Logistikk Og Lager AS | Transport & logistics | 2024 |
| TK Byggteam AS | Construction | 2021 |
| TK Verksted Holding AS | Other services | 2025 |
| TNC AS | Professional & scientific | 2020 |