| Roger Thorbjørnsrød AS | Real estate | 2013 |
| Rosenborgveien 13B AS | Real estate | 2026 |
| Sajalian Invest AS | Real estate | 2024 |
| Samp People AS | Professional & scientific | 2015 |
| Scandoi Company AS | | 2012 |
| Scandoimed AS | Health & social care | 2022 |
| Selbak Blikkenslagerverksted AS | Construction | 1990 |
| Selbak Brygge AS | Real estate | 2018 |
| Selbak Frisørsenter AS | Other services | 2018 |
| Selbak Pizza AS | Hospitality | 2017 |
| Selbak Sentrum Solstudio AS | Other services | 2011 |
| Selbak Tannlegesenter AS | Health & social care | 2013 |
| Sellebakk Bygg AS | Construction | 2026 |
| Sellebakk Herre Og Dame Frisør AS | Other services | 2022 |
| Sellebakk Hud Og Fotpleie AS | Other services | 2017 |
| Sellebakk Legekontor AS | Health & social care | 2022 |
| Sellebakk Sport Bjørg Og Kjell Storhaug Ans | | 1974 |
| Sellebakk Synssenter AS | Wholesale & retail | 2010 |
| Selva Mekaniske AS | Manufacturing | 2026 |
| Service Og Utleie AS | Real estate | 2007 |
| Servicehjelperen AS | Transport & logistics | 2022 |
| SERVICES24 AS | Transport & logistics | 2025 |
| Sidsel's Klær & Stæsj AS | Wholesale & retail | 2024 |
| Simag Holding AS | | 2024 |
| Siv.Ing. Arnbjørn Kulbrandstad AS | Professional & scientific | 2018 |
| Skiing AS | | 2008 |
| Skipsrederiet AS | Real estate | 2020 |
| Skjærviken Barnehage AS | Education | 2019 |
| Skjærviken Snekkerservice AS | Construction | 2026 |
| Skogveien AS | Real estate | 2020 |
| Smud Utleie AS | Administrative & support | 2020 |
| Solarconsulting AS | Professional & scientific | 2023 |
| Spesialist Collegium Stephane Barbari AS | Health & social care | 2002 |
| Stedjeberg Holding AS | | 2025 |
| Storaas Holding AS | Financial services | 2018 |
| Sunset Eiendom AS | | 2025 |
| Svendgaard Holding AS | | 2023 |
| Syn-Holding AS | Wholesale & retail | 2017 |
| Syvsoveren Norge AS | Manufacturing | 2024 |
| T Johannessen Holding AS | Construction | 2021 |
| T.A. Multiservice AS | Manufacturing | 2016 |
| T.E.Gundersen AS | Health & social care | 2024 |
| T.V.D. Musikkinstrument Akademiet AS | Education | 2011 |
| Tegneri Talera AS | Education | 2018 |
| Tempest Invest AS | Real estate | 2014 |
| Terapihuset AS | Health & social care | 2019 |
| Tgpnorge AS | Wholesale & retail | 2019 |
| TH Expert Cleaners AS | Administrative & support | 2026 |
| The Manage Studio AS | Professional & scientific | 2025 |
| Thomsen Kran Og Transport AS | Transport & logistics | 2017 |
| Tolmer AS | Wholesale & retail | 1999 |
| Tommeliten Familiebarnehage AS | Education | 2023 |
| Toriva Holding AS | Real estate | 1991 |
| Torsnes AS | Wholesale & retail | 2019 |
| Torstad Eiendom AS | Real estate | 2024 |
| Trippen Kafeteria Ans | Hospitality | 1989 |
| TTR Bygg AS | Construction | 2024 |
| Tæsselædden AS | Manufacturing | 2021 |
| Unisave Ans | Administrative & support | 2003 |
| Ve Dahlen Holding AS | | 2021 |
| Vesten Holding AS | Manufacturing | 2005 |
| Vevelstad Holding AS | Real estate | 2012 |
| Viken Boligeiendom AS | Real estate | 2021 |
| Viken Bygg Service AS | Construction | 2021 |
| Ville Villekulla Familiebarnehage AS | Education | 2013 |
| Vispen Grendehus SA | Real estate | 2023 |
| Vispen Private Barnehage Da | Education | 2004 |
| Visterveien 33 AS | Real estate | 2021 |
| Vital-Kontakt AS | Manufacturing | 2007 |
| Vitee Thai Takeaway AS | Hospitality | 2015 |
| VJT Håndverk AS | Construction | 2026 |
| W. Lene Jørgensen AS | | 2024 |
| Wa Holding Fredrikstad AS | Financial services | 2015 |
| Wika Holding AS | Manufacturing | 2024 |
| Wika Prodesign AS | Professional & scientific | 2024 |
| Xerxes Invest AS | Real estate | 2006 |
| Yasashi Head Spa AS | Other services | 2024 |
| Zelda Invest AS | Financial services | 2005 |
| Zimba Holding AS | | 2023 |
| ZK Holding AS | Professional & scientific | 2020 |
| Ødegaard Eiendom AS | Real estate | 1998 |
| Ødegaard Holding AS | Real estate | 2024 |
| Øst Rørservice AS | Construction | 2015 |
| Østerberget AS | Real estate | 2021 |
| Østfold Asfalt AS | Construction | 2009 |
| Østfold Bygg Tjenester AS | Construction | 2017 |
| Østfold Vann & Varme AS | Construction | 2023 |
| Østsiden Bemanning AS | Construction | 2021 |
| Østsiden Dyreklinikk AS | Professional & scientific | 2017 |
| Østsiden Kampsportsenter AS | Education | 2021 |