| Smilebox AS | Administrative & support | 2023 |
| Smiley Accounting AS | Professional & scientific | 2014 |
| Smithestrømv 5 Eiendom AS | Real estate | 2016 |
| Smoky King 1978 AS | Hospitality | 2022 |
| Smrh AS | | 2023 |
| Smrtfisk Holding AS | | 2024 |
| Småge Invest AS | | 2019 |
| Smørstein AS | | 2025 |
| SN Analyse AS | Professional & scientific | 2022 |
| Snackis Da | Wholesale & retail | 2006 |
| Snappy's Grill Ans | Hospitality | 2012 |
| Snappys Bragernes AS | Hospitality | 2004 |
| Snappys Grill Rundtom AS | Hospitality | 2025 |
| Sneaky Blinders AS | Information & communication | 2005 |
| Snee AS | Construction | 2010 |
| SNH Invest AS | Financial services | 2005 |
| Snorre Import Ans | Wholesale & retail | 1994 |
| Snri Holding AS | | 2026 |
| Snurrebass AS | | 2023 |
| Socium AS | Wholesale & retail | 2012 |
| Socle AS | Hospitality | 2026 |
| Soeek Holding AS | Financial services | 2010 |
| Sofus & Oscar AS | Hospitality | 2004 |
| Soil Mates AS | Wholesale & retail | 2024 |
| Solan Anlegg AS | Professional & scientific | 2025 |
| Solbakken 10 AS | Real estate | 2022 |
| Solberg Group AS | | 2005 |
| Solberg Group Holding AS | Real estate | 2020 |
| Solberg Spinderi Holding AS | Real estate | 2019 |
| Solberg Teglverk Eiendom AS | Real estate | 2005 |
| Solbergelva Utvikling AS | Real estate | 2021 |
| Solbø Invest AS | Financial services | 2015 |
| Soldekke AS | Energy | 2023 |
| Soleim Abrahamsen AS | | 2020 |
| Solem Helse AS | Health & social care | 2024 |
| Solengen AS | Professional & scientific | 1997 |
| Solengen Eiendom AS | Real estate | 1998 |
| Solengen Holding AS | Professional & scientific | 2005 |
| Soletinos AS | | 2026 |
| Soleveien AS | Real estate | 2016 |
| Solhan Da | Wholesale & retail | 2001 |
| Solhellinga 37 AS | Construction | 2020 |
| Solid Holding AS | Real estate | 2020 |
| Solide AS | Professional & scientific | 2025 |
| Sollegene AS | Health & social care | 2023 |
| Solli Arkitektur & Landskap AS | Professional & scientific | 1991 |
| Solliafarmen Catering & Bakeri AS | Hospitality | 2024 |
| Solo Førland AS | Real estate | 2012 |
| Solreiser AS | Professional & scientific | 2023 |
| Solren AS | Other services | 2026 |
| Soltanian Invest AS | Real estate | 2020 |
| Solum Music Da | Arts & recreation | 2012 |
| Solumlund Invest AS | Real estate | 2021 |
| Solutioneering AS | Professional & scientific | 2025 |
| Solvask AS | Other services | 1990 |
| Solveigs Holding AS | Hospitality | 2021 |
| Solås Kabel TV SA | Information & communication | 1992 |
| Sommita Da | Wholesale & retail | 2009 |
| Sone Eiendom AS | Real estate | 2020 |
| SONE99 AS | Professional & scientific | 2017 |
| Sonic Sense AI AS | Information & communication | 2024 |
| Sonja Studio AS | Education | 2024 |
| Sooma AS | Professional & scientific | 2014 |
| Sophies Rede AS | Wholesale & retail | 2026 |
| Sophus Invest AS | | 2020 |
| Sorbel Consulting AS | Professional & scientific | 2024 |
| Sorbs AS | Water & waste | 2021 |
| Sorli Invest Holding AS | | 2021 |
| Soror Eiendom AS | Real estate | 2023 |
| Sortec AS | | 2026 |
| Sortiment AS | Information & communication | 2011 |
| Sos Avløp AS | Construction | 2022 |
| Sosial Sone AS | Administrative & support | 2019 |
| Sosioraster AS | Professional & scientific | 2011 |
| Soumah Renhold Sekou | Administrative & support | 2013 |
| Sound People AS | Wholesale & retail | 1993 |
| Soundbay Music AS | Arts & recreation | 2009 |
| Sovereign Invest AS | | 2021 |
| Sovl AS | | 2026 |
| Spa Norge AS | Health & social care | 2021 |
| SPACE24ANDUP AS | Information & communication | 2025 |
| Spadanor AS | Professional & scientific | 2019 |
| Sparebanken Øst Boligkreditt AS | Financial services | 2009 |
| Sparebanken Øst Eiendom AS | Real estate | 1988 |
| Sparekortet Da | Administrative & support | 2002 |
| Spares.No - Mobil Tilbehør Og Reservedeler Nuf | Wholesale & retail | 2022 |
| Sparsom AS | Information & communication | 2026 |
| Spearhead AS | | 2025 |
| Spectralytics AS | Information & communication | 2025 |
| Spectrum Sport Ans | Wholesale & retail | 1994 |
| Spektrum Bil AS | Wholesale & retail | 2025 |
| Spent AS | | 2020 |
| Spentari AS | Wholesale & retail | 2017 |
| Sperton Global AS | Administrative & support | 2015 |
| Sperton Norway AS | Administrative & support | 2020 |
| Spesialboden AS | Wholesale & retail | 1988 |
| Spesialistklinikken Union Brygge AS | Health & social care | 2016 |
| Spex Media AS | Information & communication | 2025 |
| Spicehouse AS | Hospitality | 2024 |
| Spicemaster AS | Hospitality | 2020 |