| Sandefjord Foreningsbingo AS | Arts & recreation | 2012 |
| Sandefjord Fotball AS | Arts & recreation | 1993 |
| Sandefjord Fotosenter AS | Wholesale & retail | 2008 |
| Sandefjord Frukt Og Grønt AS | Wholesale & retail | 2018 |
| Sandefjord Golfsenter AS | Arts & recreation | 2021 |
| Sandefjord Helsepark Legene Syd AS | Health & social care | 2011 |
| Sandefjord Hjerteklinikk AS | Health & social care | 2026 |
| Sandefjord Husdyr AS | Agriculture & fishing | 2014 |
| Sandefjord Industrieiendom AS | Real estate | 2022 |
| Sandefjord Kjøkkensenter AS | Wholesale & retail | 2021 |
| Sandefjord Legesenter Da | Health & social care | 2024 |
| Sandefjord Lufthavn AS | Transport & logistics | 2024 |
| Sandefjord Lufthavn Drift AS | Transport & logistics | 1959 |
| Sandefjord Lufthavn Eiendom AS | Real estate | 2024 |
| Sandefjord Maskin & Hagedesign AS | Construction | 2022 |
| Sandefjord Maskin Ans | Agriculture & fishing | 2011 |
| Sandefjord Maskin AS | Construction | 2007 |
| Sandefjord Maskinutleie AS | Administrative & support | 2004 |
| Sandefjord MHP AS | Health & social care | 2010 |
| Sandefjord Og Andebu Eiendomsmegling AS | Real estate | 2011 |
| Sandefjord Ortopedi AS | Health & social care | 2019 |
| SANDEFJORD PERSIENNE OG MARKISEFABRIKK Jensen og Evensen ANS | Manufacturing | 1988 |
| Sandefjord Proteselaboratorium AS | Manufacturing | 2017 |
| Sandefjord Rør & Industriservice AS | Manufacturing | 2021 |
| Sandefjord Rørfornying AS | Construction | 2026 |
| Sandefjord Rørhandel AS | Construction | 2009 |
| Sandefjord Sikkerhetstjeneste Da | Wholesale & retail | 1997 |
| Sandefjord Skilt- Og Glassgravering Kristiansen Ans | Manufacturing | 1989 |
| Sandefjord Stenhuggeri AS | Manufacturing | 2000 |
| Sandefjord Sushi AS | Hospitality | 2020 |
| Sandefjord Sykkelsenter AS | Wholesale & retail | 1998 |
| Sandefjord Taksering Og Byggtjenester AS | Professional & scientific | 1999 |
| Sandefjord Tannregulering AS | Health & social care | 2016 |
| Sandefjord Taxi AS | Transport & logistics | 1995 |
| Sandefjord Trafikkskole AS | Education | 2012 |
| Sandefjord Treningssenter AS | Arts & recreation | 2026 |
| Sandefjord Utvikling AS | Real estate | 2016 |
| Sandefjord Vaktmester AS | Administrative & support | 2024 |
| Sandefjord Ventilasjon AS | Construction | 2024 |
| Sandefjord Verktøyindustri AS | Real estate | 1975 |
| Sandefjord Vinfestival AS | Arts & recreation | 2025 |
| Sandefjord Øre-Nese-Hals AS | Health & social care | 2009 |
| Sandefjordbilservice AS | Other services | 2020 |
| Sandefjordgruppen Invest AS | Financial services | 2017 |
| Sandefjords Blad AS | Information & communication | 2014 |
| Sandero AS | | 2014 |
| Sandra Huseklepp AS | Professional & scientific | 2022 |
| Sanna Salgscoaching AS | Professional & scientific | 2014 |
| Sanook AS | | 2019 |
| Sans Delikatesse & Catering AS | Hospitality | 2012 |
| Sans Mat & Vin AS | Hospitality | 2017 |
| Santrade AS | Wholesale & retail | 2019 |
| Sapconsulto AS | Information & communication | 2016 |
| Saphir AS | Real estate | 1998 |
| Saraswati AS | Wholesale & retail | 2005 |
| Sarimon Psykolog Tjenester AS | Health & social care | 2021 |
| SAS Bygg AS | Real estate | 2026 |
| SAS Elektro AS | Construction | 2000 |
| Satech AS | Wholesale & retail | 2016 |
| Saubakken Va-Drift SA | Water & waste | 2026 |
| Saubakken Va-Prosjekt SA | Water & waste | 2026 |
| Savestrum AS | Professional & scientific | 2026 |
| Saxebygg AS | Real estate | 2005 |
| Saygin Barbershop AS | Other services | 2015 |
| Scalebridge AS | Professional & scientific | 2024 |
| Scan Drilling AS | Construction | 2022 |
| Scan Granitt AS | Manufacturing | 1998 |
| Scan Style Norge AS | Wholesale & retail | 2023 |
| Scanap AS | Professional & scientific | 1999 |
| Scandi Line Sandefjord-Strømstad Nuf | Professional & scientific | 2006 |
| Scandic American Shipping Ltd (European Branch) Nuf | Transport & logistics | 2004 |
| Scandinavian Cal-Look Classic AS | Wholesale & retail | 2016 |
| Scandiport Ans | | 1988 |
| Scanplast & Co AS | Manufacturing | 2003 |
| Scanwaste AS | Wholesale & retail | 2003 |
| Schau & Partners AS | Transport & logistics | 2006 |
| Scheie AS | Wholesale & retail | 1998 |
| Schjelderup AS | Information & communication | 2017 |
| Schjelderup Technology AS | Professional & scientific | 2023 |
| Schulstok Holding AS | | 2023 |
| Schulze & Co Aksjeselskap | Construction | 2022 |
| SCN AS | Information & communication | 2014 |
| SE Skotheim Investment AS | Information & communication | 2006 |
| Seannovation AS | Professional & scientific | 2023 |
| Seannovation Coinvest AS | Financial services | 2024 |
| Seannovation Production AS | Manufacturing | 2024 |
| Seaside Asnes AS | Financial services | 2013 |
| Seaside Marina AS | Wholesale & retail | 2016 |
| Seaside Marina Eiendom AS | Real estate | 2014 |
| Sebbe Invest AS | | 2021 |
| Secloud AS | Information & communication | 2019 |
| Secma AS | Wholesale & retail | 2013 |
| Sector Bolig AS | Real estate | 2025 |
| Sector Eiendom AS | Real estate | 2006 |
| Secure IT Environment AS | Professional & scientific | 2002 |
| Security Eiendom AS | | 2011 |
| Seim Asfalt AS | Construction | 2020 |
| Seim Gjerde AS | Construction | 2012 |
| Seim Maskin AS | Construction | 2009 |
| Seim Og Moland Invest AS | Real estate | 2021 |