| Sprocket AS | | 2026 |
| SSB Capital AS | Real estate | 2025 |
| St.Hanshaugen Industrier AS | Real estate | 2014 |
| Stabækhøi Eiendom AS | | 2026 |
| Star Finans AS | Real estate | 2021 |
| Star Motor AS | Other services | 1977 |
| Star Motor Eiendom AS | Real estate | 2019 |
| Star Motor Holding AS | Other services | 2021 |
| Startboxes Da | Information & communication | 2010 |
| Startspin Limited Nuf | Information & communication | 2006 |
| Statera Clinic AS | Health & social care | 2022 |
| Statsoft Norway AS | Information & communication | 2006 |
| Steam & Stir Sandvika AS | Hospitality | 2025 |
| Steamheads AS | Information & communication | 2015 |
| Stiberg Holding AS | Professional & scientific | 2018 |
| Stig a Dalen AS | Wholesale & retail | 1976 |
| Stig Dalen Invest AS | Wholesale & retail | 2005 |
| Stiklen AS | Financial services | 2005 |
| Storkringla AS | Wholesale & retail | 2003 |
| Stormfelt & Co AS | Real estate | 2025 |
| Straa AS | Professional & scientific | 2018 |
| Strand Berentzen AS | Other services | 2023 |
| Strandgata 3 Eiendom AS | Real estate | 2017 |
| Strandsonen AS | Wholesale & retail | 2017 |
| Strandy AS | Hospitality | 2023 |
| Strategisk Institutt AS | Professional & scientific | 2001 |
| Streamworks AS | Information & communication | 2020 |
| Studio 101 Da | Information & communication | 2016 |
| Studio M3 AS | Professional & scientific | 2011 |
| Ståvihagan Samvirke SA | Real estate | 1983 |
| Subsea Installer AS | Professional & scientific | 2012 |
| Subsea Solutions Partner AS | Professional & scientific | 2011 |
| Suleiman Og Izabella Frisør AS | Other services | 2023 |
| Sumu AS | | 2019 |
| Sundheim Madison Business Communication AS | Professional & scientific | 1990 |
| Sundsbø Holding AS | Real estate | 2020 |
| Sve Finans AS | Wholesale & retail | 1991 |
| Sve Profilgaver AS | Wholesale & retail | 2008 |
| Svein Svendsen & Sønn Trafikkskole AS | Education | 2004 |
| Sveka AS | Real estate | 1998 |
| Svend Dahle Holding AS | Real estate | 2005 |
| Svendåsrud AS | | 2025 |
| SVK26 Wine & Dine AS | Hospitality | 2025 |
| Swah AS | Wholesale & retail | 2021 |
| Symbi AS | | 2015 |
| Synoptik Norge AS | Wholesale & retail | 1985 |
| T. Benum AS | Professional & scientific | 2022 |
| T3 Rådgivning AS | Professional & scientific | 2019 |
| Tafika Maitso AS | | 2020 |
| Takst&Tømrerpartner AS | Professional & scientific | 2026 |
| Takvindu AS | Construction | 2018 |
| Talina AS | Financial services | 2005 |
| Talén AS | Professional & scientific | 2014 |
| Tannlege Buer Temp AS | Health & social care | 2026 |
| Tannlege Busklein AS | Health & social care | 2026 |
| Tannlege Busklein Drift AS | Health & social care | 2026 |
| Tannlege Busklein Holding AS | | 2026 |
| Tannlege Malinn Ødegaard AS | Health & social care | 2020 |
| Tao Norway AS | Health & social care | 2007 |
| Tapetgalleriet Sandvika AS | Wholesale & retail | 2007 |
| TBC Records AS | Information & communication | 2018 |
| Technip India Limited | Administrative & support | 2012 |
| Technogarden Albatross Prosjektledelse AS | Professional & scientific | 1992 |
| Technogarden AS | Administrative & support | 2003 |
| Technogarden Human Resources AS | Administrative & support | 1984 |
| Telekiosken Super Store Sandvika AS | Wholesale & retail | 2013 |
| Tellit Solutions AS | Information & communication | 2007 |
| Tenkfrem AS | Professional & scientific | 2024 |
| Tenvig Finans AS | Real estate | 2017 |
| Teo-Team Import Ans | | 1989 |
| Teraconsult AS | Information & communication | 2021 |
| Terva Holding AS | | 2026 |
| Teva Norway AS | Wholesale & retail | 2000 |
| Texdecor SAS Nuf | Manufacturing | 2008 |
| Thal Eiendom AS | Real estate | 2017 |
| The Barber Shop AS | Other services | 2020 |
| The BBQ Shop AS | Wholesale & retail | 2015 |
| The Gym Industry AS | Wholesale & retail | 2022 |
| Thomas Heftyesgate 62 AS | Households | 1916 |
| Thomas Leker Kozmos Sandvika AS | Wholesale & retail | 2023 |
| Thomas Leker Sandvika AS | Wholesale & retail | 2023 |
| Tik Investering AS | Financial services | 2007 |
| Tika Time AS | Hospitality | 2014 |
| Tilmobil Da | Wholesale & retail | 2013 |
| Timian AS | Hospitality | 2004 |
| Tinka Fortuna AS | | 2020 |
| TM Team AS | Construction | 2025 |
| Tojet AS | | 2001 |
| Tommi Salongen Sandvika Storsenter AS | Other services | 1993 |
| Tonic Father AS | Professional & scientific | 2021 |
| Toothfairy AS | Arts & recreation | 2005 |
| Toothfairy Publishing AS | Information & communication | 2024 |
| Toothfairy Servering AS | Hospitality | 1985 |
| Topwash AS | Other services | 2008 |
| Tor Rustad Prosjekt AS | | 2022 |
| Torshov Handelseiendom AS | Real estate | 2018 |
| Touriga Nacional AS | Professional & scientific | 2007 |
| Tove Mette's NC Ans | Wholesale & retail | 1995 |
| Transforceyoosh AS | Transport & logistics | 2026 |
| Trelll AS | Information & communication | 2025 |