| Din Seksualitet AS | Health & social care | 2022 |
| Dio Enterprise AS | Manufacturing | 1986 |
| Dohtech AS | | 2021 |
| Donàdi Da | Wholesale & retail | 2026 |
| Drivhuset I Horten AS | Education | 2023 |
| Druidgaarden AS | Real estate | 2016 |
| Dørstad Grapes AS | Wholesale & retail | 2017 |
| Dørstad Holding AS | Wholesale & retail | 2019 |
| E M Agenturer AS | Wholesale & retail | 2009 |
| E Q Holdco AS | Manufacturing | 2021 |
| E.F. Jimenez Rørservice AS | Construction | 2016 |
| E.M. Holding AS | Wholesale & retail | 2009 |
| Ecas AS | Manufacturing | 1986 |
| Ecurie Phønix AS | Agriculture & fishing | 2021 |
| Edle Dråper Import AS | Wholesale & retail | 2022 |
| Eiken Bygg AS | Construction | 2022 |
| Einertoppen AS | Real estate | 2024 |
| Ekko Bravo AS | Information & communication | 2024 |
| Ekvator Eiendom AS | Real estate | 2012 |
| El-Bygg AS | Construction | 2016 |
| Elite Training Group AS | Arts & recreation | 2013 |
| Elkjøp Stormarked Horten AS | Wholesale & retail | 2010 |
| Eloksal AS | Manufacturing | 1993 |
| Embro AS | Information & communication | 2005 |
| Embro Eiendom AS | Real estate | 2003 |
| Emp Holding AS | | 2023 |
| Enso Denmark AS | Wholesale & retail | 2023 |
| Enso Norway AS | Wholesale & retail | 2014 |
| Enter Regnskap AS | Professional & scientific | 2012 |
| Eo Eiendom AS | Real estate | 2014 |
| Epiphany Dental AS | | 2018 |
| Eqom Norway AS | Wholesale & retail | 1987 |
| Erichsruds Konsulenttjenester AS | Professional & scientific | 2017 |
| Erik & Runes Trading Da | | 1994 |
| Erik Gregersen Holding AS | | 2022 |
| Eritech Renhold AS | Administrative & support | 2025 |
| Erlend Morland Holding AS | Real estate | 2022 |
| Ernst Solberg AS | Real estate | 1986 |
| Esd Service AS | Wholesale & retail | 2016 |
| Eskebekk AS | Professional & scientific | 2014 |
| Espen Fjellheim Consulting AS | Financial services | 2013 |
| Essem Invest AS | Financial services | 2016 |
| Evensen Invest AS | Professional & scientific | 2018 |
| Evkå Bygg Service AS | Construction | 2019 |
| Faarikaal Designstudio AS | Professional & scientific | 2024 |
| Fabrica AS | Information & communication | 2026 |
| Faksvaag AS | Professional & scientific | 2023 |
| FALK1BERG AS | Real estate | 2020 |
| Famiglia Holdning AS | Education | 2020 |
| Famøsa AS | Financial services | 2005 |
| Fastlegene AS | Health & social care | 2019 |
| Feelgood Horten AS | Arts & recreation | 2019 |
| Felag AS | Professional & scientific | 2016 |
| Felles Media AS | Wholesale & retail | 2016 |
| Ferder Gruppen AS | Transport & logistics | 2018 |
| Ferder Taxi AS | Transport & logistics | 2017 |
| Fesjong AS | Professional & scientific | 2024 |
| FF Rollerskis AS | Wholesale & retail | 2017 |
| Fikseralt AS | Construction | 2010 |
| Fimreite Software AS | Information & communication | 2008 |
| Finder AS | Administrative & support | 2001 |
| Firing & Thorsen AS | Construction | 2003 |
| First Second AS | Information & communication | 2023 |
| Fjetland Moen Invest AS | | 2021 |
| Fjordenlegene AS | Health & social care | 2011 |
| Flavia AS | Real estate | 2005 |
| Fokus Golf AS | Administrative & support | 2021 |
| Folkets Hus Horten SA | Real estate | 1995 |
| Food Industry Consulting AS | Professional & scientific | 2026 |
| Fotograf Helle K. Hagen AS | Professional & scientific | 2013 |
| Fox Invest Holding AS | | 2023 |
| Fram Kapital AS | | 2026 |
| Frantzens Husholding AS | Professional & scientific | 2024 |
| Fremmedart AS | Wholesale & retail | 2015 |
| Fresia AS | | 2023 |
| Friberg Bygg Og Interiør AS | Construction | 2017 |
| Friberg Holding Invest AS | Construction | 2020 |
| Friberg Renhold AS | Administrative & support | 2025 |
| Fritz Bentzen Invest AS | Construction | 2005 |
| Fritz Flak AS | Real estate | 2013 |
| Fron AS | Professional & scientific | 2018 |
| Frydendal AS | Professional & scientific | 2023 |
| Furious AS | Information & communication | 2016 |
| Fysio Atletika AS | Health & social care | 2024 |
| G Tech Invest AS | | 2021 |
| Galleberg Veiledningstjenester AS | Arts & recreation | 2023 |
| Gamleveien 55 AS | Real estate | 2006 |
| Gardini AS | Health & social care | 2016 |
| Garnhexene AS | Wholesale & retail | 2018 |
| Gas-Come Marine Motors AS | Construction | 2020 |
| Ge Vingmed Ultrasound AS | Manufacturing | 1985 |
| Gecom AS | Construction | 1985 |
| Gemsys Etikett AS | Professional & scientific | 2005 |
| Gentek AS | Professional & scientific | 2026 |
| Gingersons AS | Arts & recreation | 2018 |
| Gio Accounting Services AS | Professional & scientific | 2017 |
| Gjengangeren AS | Information & communication | 2014 |
| Gjersjøen Golfbane AS | Arts & recreation | 2013 |
| Glenns Bildeler AS | Wholesale & retail | 1989 |
| Global Sun Nuf | | 2007 |