| Setre SA | Construction | 2003 |
| Sew-Eurodrive AS | Manufacturing | 1977 |
| SGM Bygg AS | Construction | 2023 |
| SH Consult Limited Nuf | Information & communication | 2010 |
| SH Investments Nuf | Real estate | 2011 |
| Shaiva Tantra AS | Education | 2025 |
| SHANGRI STORKIOSK GATEKJØKKEN OG VIDEO DA Baig Hussain & Ashi | Hospitality | 1989 |
| Shanson - Art of Living AS | Education | 2013 |
| Sharon Invest AS | Information & communication | 2023 |
| Shaugen Holding AS | Real estate | 2021 |
| SHB Trading AS | Wholesale & retail | 2016 |
| Sherpa Invest Limited Nuf | Real estate | 2007 |
| Shoeday Norge AS | Wholesale & retail | 1983 |
| Shredder Offshore AS | Professional & scientific | 2020 |
| Signalveien 4 AS | Real estate | 2008 |
| Sikkerhetsproffen AS | Professional & scientific | 2023 |
| Silentia Norge AS | Wholesale & retail | 2021 |
| Silverman AS | | 2025 |
| Silvija Studio AS | Professional & scientific | 2024 |
| Simcura AS | Information & communication | 2026 |
| Simh Invest AS | | 2017 |
| Simkvi AS | Real estate | 2021 |
| Sinding AS | Professional & scientific | 2013 |
| Singularis AS | Information & communication | 2025 |
| Site Service Bane AS | Construction | 2020 |
| Siv. Ing. Trond Stang AS | Real estate | 2012 |
| SJB Holding AS | | 2009 |
| Sjolte AS | | 2025 |
| Sjøfront Utvikling AS | Real estate | 2019 |
| Sjøgata 2 AS | Real estate | 2004 |
| Sjøgata 25 Moss AS | Real estate | 2006 |
| Sjøhagen Bolig AS | Real estate | 2007 |
| Sjøhagen Fus Barnehage AS | Education | 2018 |
| Sjøhaug Naturistsenter SA | Hospitality | 1980 |
| Sjøsiden Moss AS | Real estate | 2015 |
| SK Eiendom Og Utvikling AS | Construction | 2021 |
| Sk's Grill & Pizza AS | Hospitality | 2023 |
| Skaar Invest AS | Financial services | 2009 |
| Skafu Eiendom AS | Real estate | 2005 |
| Skagevang Holding AS | | 2024 |
| Skandinavisk Kommunalteknikk AS | Professional & scientific | 2010 |
| Skarnes Butikkeiendom AS | Real estate | 1997 |
| Skatteeksperten II AS | Professional & scientific | 2021 |
| Skeidar Moss AS | Wholesale & retail | 1993 |
| Skinbysj AS | Other services | 2026 |
| Skinstar AS | Wholesale & retail | 2024 |
| Skjeberg Prosjektutvikling AS | Real estate | 2017 |
| Skjebergveien 123-125 AS | Real estate | 2024 |
| SKL Invest AS | Financial services | 2010 |
| Skoggata 1 AS | Real estate | 2000 |
| Skoland AS | Wholesale & retail | 1983 |
| Skolt Eiendom AS | Real estate | 2005 |
| Skolt Holding AS | Construction | 1986 |
| Skolt Miljøpark AS | Construction | 1978 |
| Skolt Næringspark Moss AS | Real estate | 2017 |
| Skolt Pukkverk AS | Mining & quarrying | 1992 |
| Skolt Utvikling AS | Real estate | 2000 |
| Skomaskiner AS | Wholesale & retail | 2014 |
| Skredderveien 132 AS | Real estate | 2021 |
| Skredderveien 6 AS | Real estate | 2000 |
| Skredderåsen Næringspark AS | Real estate | 2000 |
| Skudal Transport AS | Transport & logistics | 1992 |
| SL Stenlegging AS | Construction | 2005 |
| Slamtransportøren AS | Transport & logistics | 2024 |
| Sleiban AS | Health & social care | 2018 |
| Smart Data Da | Wholesale & retail | 2000 |
| Smart Tenkt Eiendomdrift AS | Administrative & support | 2023 |
| Smartcuts Da | Other services | 2002 |
| Smarte Bygg AS | Professional & scientific | 2015 |
| Smedbo AS | Real estate | 1996 |
| Smil Holding AS | Administrative & support | 2024 |
| Smil Renhold AS | Administrative & support | 2021 |
| Smil-Eiendom AS | Real estate | 2024 |
| SML Games AS | Manufacturing | 2020 |
| SN Asia Mat AS | Wholesale & retail | 2021 |
| SN Living AS | Real estate | 2021 |
| Snekkertjeneste AS | Construction | 2020 |
| Snellman Petfood AS | Wholesale & retail | 2023 |
| Snuppa AS | Real estate | 2016 |
| Soco Holding AS | Information & communication | 2005 |
| Sofie Forsaa Holding AS | Administrative & support | 2023 |
| Sofies Reiser AS | Administrative & support | 2023 |
| Softpro AS | Real estate | 2012 |
| Sofus Klær AS | Wholesale & retail | 1997 |
| Sohrabi Eiendom AS | Real estate | 2005 |
| Sohrabi Holding AS | | 2018 |
| Sokeynas Familiebarnehage AS | Education | 2025 |
| Solan Eiendom AS | Real estate | 1997 |
| Solan Invest AS | Real estate | 1994 |
| Solar Moss AS | Professional & scientific | 2020 |
| Solar Solution AS | Wholesale & retail | 2012 |
| Solbakken Team Holding AS | Real estate | 2005 |
| Solgaard Eiendom AS | Real estate | 2019 |
| Solgaard Skog 110 Eiendom AS | Real estate | 2013 |
| Solgaard Skog 116 AS | Real estate | 2014 |
| Solgaard Skog 2 AS | Real estate | 2014 |
| Solgaard Skog 9 AS | Real estate | 2013 |
| Solgaardskog AS | Real estate | 2025 |
| Solgård 120 AS | Wholesale & retail | 2008 |
| Solgård Skog 1 AS | Real estate | 2023 |