| HK2 Eiendom AS | Real estate | 2017 |
| Hli AS | Professional & scientific | 2026 |
| HM Eiendom & Renovering AS | Real estate | 2020 |
| HN Production AS | Information & communication | 2021 |
| HN Prosjektsupport AS | Professional & scientific | 2017 |
| Ho Eiendom Invest AS | Real estate | 2012 |
| Holistisk Human Design AS | Education | 2025 |
| Holla Holding AS | Financial services | 2010 |
| Holm & Tall AS | Information & communication | 2026 |
| Holmestrand Bolig AS | Real estate | 2022 |
| Holtarstaulen AS | Real estate | 2020 |
| Holte Utvikling AS | | 2022 |
| Holwa AS | Transport & logistics | 2024 |
| Home Hotel Vic AS | Hospitality | 2026 |
| Honeyjar AS | | 2020 |
| Horse & Rider AS | Administrative & support | 2018 |
| Horten Hotell Eiendom AS | Real estate | 2016 |
| House of Bjørk AS | Wholesale & retail | 2021 |
| Hovenga AS | Real estate | 2023 |
| Hovenga Autosenter AS | Wholesale & retail | 2017 |
| Hovenga Rep Service AS | Manufacturing | 2016 |
| Hovenga Sko AS | Wholesale & retail | 2000 |
| Hovholt Gård Utbygging AS | Real estate | 2023 |
| HP Invest AS | | 2018 |
| Hrhartveit Invest AS | | 2025 |
| HRJ Finne Holding AS | Real estate | 2020 |
| HRL Entreprenør AS | Construction | 2004 |
| HS Flis Mur Og Puss AS | Construction | 2023 |
| Hse Telemark AS | Health & social care | 2017 |
| HSK Investering AS | | 2026 |
| Huken 5 AS | Real estate | 2004 |
| Huken Eiendom AS | Real estate | 2022 |
| Huken Utvikling AS | Real estate | 2023 |
| Humble Holding AS | | 2023 |
| Humlebæk Eiendom AS | Real estate | 2016 |
| Huset Med Det Rare I Da | Wholesale & retail | 1996 |
| Husfliden AS | Wholesale & retail | 2003 |
| Hvalen Invest AS | Real estate | 2014 |
| Hvelvet Design Da | Wholesale & retail | 1998 |
| Hvem Eier Bilen Da | Administrative & support | 2022 |
| Hvem-Eier-Bilen.No Da | Administrative & support | 2022 |
| HVT Invest AS | | 2021 |
| Hydrogenpro ASA | Manufacturing | 2013 |
| Hygea Helse & Bandasje AS | Wholesale & retail | 1991 |
| Hytte-Drøm AS | Real estate | 2018 |
| Hytter AS | Construction | 2020 |
| Herøya Renhold Nilsen ANS | Wholesale & retail | 1988 |
| Håndtverker H Eiendom AS | Construction | 2025 |
| Håndverksvegen 1 AS | Real estate | 2019 |
| Håndverksvegen 15 AS | Real estate | 2015 |
| Håndverksvegen 5 AS | Real estate | 2022 |
| Håtveit-Holding AS | | 2024 |
| Hæreid Eiendom AS | Wholesale & retail | 1993 |
| Hæreid Holding AS | Wholesale & retail | 2005 |
| Høpek AS | Real estate | 2013 |
| Høyne AS | Real estate | 2014 |
| I Siste Lita Event AS | Administrative & support | 2022 |
| I3 Computer Consulting Da | Information & communication | 2001 |
| Iaat Holding AS | | 2021 |
| Ias Holding AS | | 2026 |
| Ibeco AS | Wholesale & retail | 2018 |
| Ibenor AS | Financial services | 2012 |
| Iform Porsgrunn AS | Arts & recreation | 2016 |
| Ifront Consulting AS | Professional & scientific | 2024 |
| Ikeso Consulting Da | Administrative & support | 2001 |
| Ikeso Eiendom Da | Real estate | 2000 |
| Ikke Bare Brød AS | Manufacturing | 2025 |
| Illeris AS | Information & communication | 2014 |
| Illuminor AS | Wholesale & retail | 1993 |
| Impact Studio AS | Information & communication | 2023 |
| In Consult AS | Professional & scientific | 2017 |
| In Line Frisør AS | Other services | 2020 |
| Industri- & Sikkerhetsskolen AS | Education | 2019 |
| Industriuka AS | Administrative & support | 2024 |
| Industriveien 2 Porsgrunn AS | Real estate | 2011 |
| Industry Service AS | Administrative & support | 2017 |
| Inflowcontrol AS | Professional & scientific | 2011 |
| Ingeniør Five AS | Professional & scientific | 2011 |
| Ingeniørfirma Gullik E Bråthen AS | Professional & scientific | 2001 |
| Ingeniørtakst AS | Professional & scientific | 2019 |
| Inger-Lise Rasmussen Familieveiledning AS | Health & social care | 2026 |
| Innovator AS | Real estate | 2018 |
| Innowell Solutions AS | Professional & scientific | 2012 |
| Insert Coins AS | Real estate | 2016 |
| Installatør Per Øverland AS | Construction | 1971 |
| Institute for Learning Organizations AS | Education | 1999 |
| Institutt for Mekanisk Diagnostikk Og Terapi Norge AS | Education | 2016 |
| Inter Fish Da | Wholesale & retail | 1992 |
| Invest Tech AS | | 2012 |
| Invest Telemark AS | Real estate | 2013 |
| Invest-Lia AS | Professional & scientific | 2021 |
| Investeringsgeorg AS | Wholesale & retail | 1998 |
| Isaksen AS | Wholesale & retail | 1998 |
| Isaksen Automasjon AS | Professional & scientific | 2012 |
| Isaksen Eiendom AS | Wholesale & retail | 1972 |
| Isaksen Storgaten AS | Wholesale & retail | 1999 |
| Islandwind Holding AS | | 2025 |
| Islann Holding AS | Professional & scientific | 2018 |
| Iso Tjenester AS | Information & communication | 2022 |
| Isofag AS | Construction | 2020 |