| Advokat Espen Flagstad AS | Professional & scientific | 2026 |
| Aga Gruppen AS | Hospitality | 2024 |
| Agape Forlag AS | Information & communication | 1985 |
| Airplay Production Ans | | 1990 |
| Ak Flislegging AS | Construction | 2015 |
| Alarmlink AS | Wholesale & retail | 2015 |
| Altivo Bygg AS | Construction | 2026 |
| Amarloui AS | | 2021 |
| Anders Hunn Graving Og Transport AS | Construction | 2012 |
| Ap Betong Bygg AS | Construction | 2023 |
| Ar&Et AS | Hospitality | 2012 |
| Aranea AS | Professional & scientific | 2012 |
| Arca Nova AS | Real estate | 1998 |
| Arca Nova Bolig AS | Real estate | 2002 |
| Arca Nova Eiendom AS | Real estate | 1997 |
| Arca Nova Entreprenør AS | Construction | 2002 |
| Arca Nova Utvikling AS | Real estate | 2000 |
| Arildsborg Curlingsenter AS | Arts & recreation | 2018 |
| Ark Trade AS | Professional & scientific | 1991 |
| Ark Utvikling AS | Real estate | 1993 |
| Arkom AS | Wholesale & retail | 2019 |
| AS Grundkjen | Real estate | 1915 |
| Asett Byggservice AS | Construction | 2016 |
| Baltic Hjem AS | Construction | 2020 |
| Berg Solutions AS | Professional & scientific | 2025 |
| Bil Grossisten AS | Wholesale & retail | 2021 |
| Biomed Clinic AS | Health & social care | 2008 |
| Bjønnes Software AS | Information & communication | 2009 |
| Boholm AS | | 2015 |
| Borge Begravelsesbyrå Ellen M. Bye AS | Other services | 2014 |
| Borge Fysioterapi Da | Real estate | 2009 |
| Borge Gård Drift AS | Agriculture & fishing | 2022 |
| Borge Legesenter AS | Health & social care | 2020 |
| Borge Pukkverk AS | Mining & quarrying | 1989 |
| Bra Service AS | Administrative & support | 2012 |
| Bronova AS | Real estate | 2001 |
| Bryggeservice Østfold AS | Construction | 2018 |
| Brynhildsen Eiendom AS | Wholesale & retail | 2012 |
| Brynhildsen Holding AS | Wholesale & retail | 2005 |
| Bye & Bye Verksted AS | Other services | 2021 |
| Byggteknikk ANS | | 1988 |
| Cafe Duo Eli Larsen Og Britt Heidi Larsen Da | Hospitality | 2003 |
| Cal Trykk AS | Manufacturing | 1986 |
| Capensa AS | Administrative & support | 2017 |
| Carun AS | Education | 2002 |
| Carun Holding AS | | 2020 |
| Cirrus Invest AS | | 2018 |
| CJ Invest AS | Financial services | 2017 |
| CNC Spesialisten AS | Manufacturing | 2006 |
| Dahlbergs AS | | 2018 |
| Dano Auto AS | Wholesale & retail | 2026 |
| De Tre Musketerer AS | Administrative & support | 2000 |
| Dekkcenteret Fredrikstad AS | Other services | 1996 |
| Designgaver AS | Professional & scientific | 2024 |
| Det Gamle Bryggerhus Da | Wholesale & retail | 2014 |
| Din-Budpartner Nuf | Transport & logistics | 2010 |
| DR. Stenebråten AS | Health & social care | 2024 |
| Draupner Eiendom AS | Real estate | 2024 |
| Ehm Eiendom AS | Real estate | 2004 |
| Eker Bygg & Prosjekt AS | Real estate | 1986 |
| Ekstra Sjåfør AS | | 2026 |
| El Cartel AS | Arts & recreation | 2020 |
| Elektromek Servicepartner Da | Manufacturing | 1998 |
| Emp Invest AS | Real estate | 2019 |
| Energi Prosjekt AS | Professional & scientific | 2019 |
| Enok Dahl Hansen AS | Construction | 2005 |
| Entromission AS | Professional & scientific | 2014 |
| Esc Holding AS | | 2021 |
| Esma Pharma AS | Wholesale & retail | 2026 |
| Evensen AS | Wholesale & retail | 2022 |
| Evig Lykke AS | Wholesale & retail | 2018 |
| F&S Bygg AS | Construction | 2021 |
| Fandango AS | Professional & scientific | 2005 |
| Favi AS | Health & social care | 1990 |
| Feldtcon AS | Professional & scientific | 1995 |
| Fin Sauna Digital AS | Information & communication | 2025 |
| Fjeld Tredesign AS | Construction | 2016 |
| Flowform AS | Manufacturing | 2021 |
| Fons AS | Wholesale & retail | 2025 |
| Fredrikstad Arkitekttjenester AS | Professional & scientific | 2017 |
| Fredrikstad Spesialprosjekt AS | Construction | 2022 |
| Frevin Holding AS | | 2026 |
| FSP Invest AS | Real estate | 2010 |
| Fundament Bolig AS | Real estate | 2024 |
| G&C Forretningsdrift AS | Other services | 2016 |
| Galtungveien AS | | 2011 |
| Geo Instrument Service Norge AS | Wholesale & retail | 1998 |
| Gevas AS | Real estate | 2007 |
| Glasaxen AS | Other services | 2015 |
| Glommen Bunkerservice AS | Wholesale & retail | 1990 |
| Golden Touch Real Estate Da | Real estate | 2005 |
| Granit Begisholli AS | Wholesale & retail | 2023 |
| Granlys Eiendom AS | Manufacturing | 1976 |
| Granlys Holding AS | Transport & logistics | 2018 |
| Granlys Transport AS | Transport & logistics | 2018 |
| Granlys Truck AS | Administrative & support | 2018 |
| Grønli Bygg AS | Construction | 2017 |
| Gul Snø AS | Hospitality | 2021 |
| Gullbekk Visuals AS | Information & communication | 2025 |
| Hallsen Holding AS | Manufacturing | 2023 |