| Essen Holding AS | | 2021 |
| Ettfett AS | Wholesale & retail | 2025 |
| Fagerliveien 2 Eiendom AS | | 2026 |
| Felion AS | | 2024 |
| FFJ Invest AS | | 2026 |
| Fint Maler Og Bygg AS | Construction | 2021 |
| Fire Security and Network Da | Construction | 2004 |
| Fjeldbo AS | Construction | 2012 |
| Fjeldbo Boligutvikling AS | Real estate | 2016 |
| Fjeldstad Prosjektering AS | Professional & scientific | 2019 |
| FKM AS | | 2017 |
| Fladstad Utvikling AS | Real estate | 2005 |
| Flexiform AS | Manufacturing | 1995 |
| Fluffin Perfect AS | Wholesale & retail | 2020 |
| Flyttexpressen AS | Transport & logistics | 2021 |
| Follo Bil AS | Wholesale & retail | 2025 |
| Follo Utemiljø AS | Administrative & support | 2019 |
| Forenede Plast Eiendom AS | Real estate | 2012 |
| Fossen Elektro AS | Construction | 2012 |
| Fossum & Isaksen AS | Construction | 2018 |
| Fossum Anlegg AS | Construction | 2002 |
| Frakina.No AS | Wholesale & retail | 2021 |
| Fredheim Maskin AS | Wholesale & retail | 2005 |
| Fredriks Pizza Og Restaurant AS | Hospitality | 2013 |
| Fremmegård Byggservice AS | Construction | 2020 |
| Fresh Deli Spydeberg AS | Wholesale & retail | 2023 |
| Friva AS | Manufacturing | 1962 |
| Friva Eiendom AS | Real estate | 2015 |
| G P AS | Construction | 1986 |
| Gamle Foss Skole AS | Real estate | 2015 |
| Gamle Veistasjonen Eiendom AS | Real estate | 2011 |
| Gas Gas Norge AS | Wholesale & retail | 2006 |
| Geir Moen AS | Construction | 1995 |
| Giga Ans | Information & communication | 2000 |
| GK Holding AS | Real estate | 1988 |
| GMW Holding AS | | 2020 |
| Graarud Holding AS | Real estate | 2018 |
| Grande Panorama AS | Real estate | 2020 |
| Grav Holding AS | Construction | 2021 |
| Grav Og Bygg AS | Construction | 2024 |
| Gravs Graveservice AS | Construction | 2009 |
| Grevlingen & Co AS | Construction | 1998 |
| Ground Zero AS | Arts & recreation | 2016 |
| Grålum Mat AS | Wholesale & retail | 1988 |
| Grønsenn AS | Real estate | 2016 |
| Grøtvedt Bygg Og Eiendom AS | Construction | 2021 |
| Gullende AS | Construction | 1996 |
| Gusi AS | | 2026 |
| H & H Frisørdrift AS | Other services | 2016 |
| H.P. Eiendom AS | Real estate | 2013 |
| Hallerud Kultursenter Da | Wholesale & retail | 2007 |
| Halvorshavn Eiendom AS | Real estate | 2012 |
| Helle Bolig AS | Real estate | 2020 |
| Helle Eiendomsselskap AS | Real estate | 2020 |
| Helle Ving AS | Real estate | 2005 |
| Hellebo AS | Real estate | 2020 |
| Hellebygg AS | Real estate | 2020 |
| Helles Thermotransport AS | Transport & logistics | 1993 |
| Hems Eiendom AS | Wholesale & retail | 2003 |
| Henrik Prestby Andersen Holding AS | Construction | 2008 |
| Henton AS | Financial services | 2005 |
| Heso Holding AS | Arts & recreation | 2009 |
| Hestengen Sport AS | Wholesale & retail | 2021 |
| Hjørnerud AS | Professional & scientific | 1996 |
| Hjørnerud Eiendom Da | Real estate | 2005 |
| Hjørnet AS | Real estate | 1984 |
| HK Ventilasjon AS | Construction | 2022 |
| Hko Holding AS | Financial services | 2015 |
| HMM AS | | 2017 |
| Hobøl Traktor AS | Manufacturing | 2009 |
| Holli Holding AS | Real estate | 2014 |
| Holli Mølle AS | Manufacturing | 2010 |
| Holm Bilpleie Da | Other services | 2005 |
| Holtet Solutions Da | | 2026 |
| Hoppestad B/E AS | Wholesale & retail | 2005 |
| Huwi AS | Information & communication | 2014 |
| Hyllibråten AS | Real estate | 2008 |
| Hyper Invest AS | Professional & scientific | 2015 |
| Håndverkerveien 5 B Og C AS | Real estate | 2020 |
| Håndverkveien 2 Eiendom AS | Real estate | 2003 |
| Ic Regnskap AS | Professional & scientific | 2017 |
| Idea Ventilasjon AS | Construction | 2015 |
| Igsi Eiendom AS | Real estate | 2009 |
| Indre Viken Eiendom AS | Real estate | 2019 |
| Indre Viken Holding AS | Construction | 2016 |
| Indre Østfold Bygg AS | Construction | 2018 |
| Indre Østfold Varme AS | Energy | 2024 |
| Ischebeck Nordic AS | Administrative & support | 2011 |
| Iø Bygg & Drift AS | Construction | 2025 |
| Jad Engineering AS | Professional & scientific | 2017 |
| Jad Invest AS | Professional & scientific | 2017 |
| Jamea Group AS | Professional & scientific | 2016 |
| Jatine AS | Real estate | 2025 |
| Jef Holding AS | Wholesale & retail | 2011 |
| Jeg Eiendom AS | Real estate | 2019 |
| Jet-Tek AS | Wholesale & retail | 2025 |
| Jga Fritid AS | Wholesale & retail | 2015 |
| Johs AS | Real estate | 2014 |
| Jordbær Øst AS | Agriculture & fishing | 2025 |
| Joveda Eiendom AS | Real estate | 2011 |