| Firmount Holding AS | Professional & scientific | 2018 |
| Firmus AS | | 2025 |
| First Agency AS | Wholesale & retail | 2023 |
| First Card AS | | 1991 |
| First Class Driver AS | Transport & logistics | 2023 |
| First Conferences Ltd | Professional & scientific | 1999 |
| First Floor AS | Real estate | 2013 |
| First Fondene AS | Financial services | 2009 |
| First House AS | Professional & scientific | 2009 |
| First Invest AS | Information & communication | 2019 |
| First Line AS | Real estate | 2001 |
| First Mover Group AS | Construction | 2017 |
| First Mover Group Holding AS | Construction | 2018 |
| First Olsen Holding AS | Real estate | 2010 |
| First Olsen Shipping Invest AS | Transport & logistics | 2002 |
| First Online Ans | Information & communication | 1999 |
| First Partners Holding 2 AS | | 2005 |
| First Partners Holding 5 AS | Financial services | 2005 |
| First Partners Holding 8 AS | Financial services | 2005 |
| First Party Class Da | Hospitality | 1996 |
| First Rank Media | Information & communication | 2019 |
| First Rent a Car Norway AS | Administrative & support | 2003 |
| First Seafood AS | Manufacturing | 2014 |
| First Securities AS | Administrative & support | 2015 |
| First Signal AS | | 2024 |
| First Step Marketing AS | Professional & scientific | 2016 |
| First Step Utvikling AS | Professional & scientific | 2012 |
| First Stop Norge AS | Wholesale & retail | 2000 |
| First Trade AS | | 2012 |
| First Wave AS | Education | 2005 |
| First Wines AS | Wholesale & retail | 2007 |
| Firstbird AS | Information & communication | 2023 |
| Firstcall AS | Administrative & support | 2017 |
| Firstday Invest AS | | 2023 |
| Firstpeople AS | Professional & scientific | 2003 |
| Firstspark AS | | 2026 |
| Firstvet Nuf | Professional & scientific | 2019 |
| Firveld Invest AS | | 2014 |
| Firyal El Hadari Holding AS | | 2024 |
| Fis Norway AS | Information & communication | 2021 |
| Fisch AS | Professional & scientific | 2023 |
| Fischer International Norge AS | Wholesale & retail | 2008 |
| Fischer Norge AS | Wholesale & retail | 2006 |
| Fischer Panda Norge AS | Wholesale & retail | 2021 |
| Fischmell AS | Information & communication | 2015 |
| Fisci AS | | 2020 |
| Fish Development AS | Financial services | 2010 |
| Fish Me Oslo AS | Hospitality | 2025 |
| Fishbone AS | Professional & scientific | 2010 |
| Fishent Holding AS | | 2024 |
| Fisher & Paykel Healthcare AB, Filial I Norge Nuf | Wholesale & retail | 2015 |
| Fisher & Young AS | Professional & scientific | 2020 |
| Fisher Scientific AS | Wholesale & retail | 1986 |
| Fisher Scientific Norway AS | Wholesale & retail | 2007 |
| Fisherman AS | Wholesale & retail | 2021 |
| Fishmasters AS | Hospitality | 2025 |
| Fishteck AS | Professional & scientific | 2013 |
| Fisk I Farta AS | Wholesale & retail | 2024 |
| Fisk Invest AS | Real estate | 2012 |
| Fisk Og Vilt Larsen AS | Wholesale & retail | 2023 |
| Fiskaa Capital AS | Financial services | 2017 |
| Fiskars Norway (Vita) AS | Wholesale & retail | 1999 |
| Fiskars Norway AS | Wholesale & retail | 2025 |
| Fiske Invest AS | | 2024 |
| Fiske Tom AS | Financial services | 2009 |
| Fiskebakken Invest AS | | 2022 |
| Fiskebonden Fredrik AS | Wholesale & retail | 2025 |
| FISKEDISK1 AS | | 2025 |
| Fiskekoia AS | Administrative & support | 2023 |
| Fiskelykken AS | Wholesale & retail | 2025 |
| Fiskergata 46 AS | Real estate | 2018 |
| Fiskeriet Bjørvika AS | Hospitality | 2020 |
| Fisketorget I Oslo AS | Wholesale & retail | 2013 |
| Fiskevollen Borettslag Barnehage SA | Education | 2008 |
| Fiskumparken B1.1 AS | Real estate | 2020 |
| Fiskumparken Holding AS | Real estate | 2025 |
| Fiskums Holding AS | | 2024 |
| Fiskvik AS | Information & communication | 2015 |
| Fiskvik Consult AS | Professional & scientific | 2015 |
| Fit Cake Oslo AS | Hospitality | 2025 |
| Fit Holding AS | | 2026 |
| Fit Life AS | Information & communication | 2026 |
| Fit to Perform AS | Professional & scientific | 2024 |
| Fitberry AS | Wholesale & retail | 2021 |
| Fitcast AS | Information & communication | 2020 |
| Fitfren AS | Information & communication | 2019 |
| Fithabs AS | Arts & recreation | 2024 |
| Fitjar Butikkeiendom AS | Real estate | 2024 |
| Fitjeans AS | Professional & scientific | 2019 |
| Fitlab AS | Wholesale & retail | 2016 |
| Fitness 51 AS | Wholesale & retail | 2026 |
| Fitness AS | Wholesale & retail | 2016 |
| Fitness Factory Norway AS | Wholesale & retail | 1989 |
| Fitness Group Nordic AS | Arts & recreation | 2009 |
| Fitness Holding AS | Wholesale & retail | 2022 |
| Fitness Instructional Tenis AS | Education | 2018 |
| Fitness Invest AS | Arts & recreation | 2022 |
| Fitness Mipco AS | | 2022 |
| Fitness Point SK AS | Arts & recreation | 2017 |
| Fitness Storo AS | Wholesale & retail | 2023 |