| Gustav Og Berta AS | Information & communication | 2016 |
| Gyltesø Vann Og Avløpslag SA | Water & waste | 2014 |
| Gårdstunet AS | Real estate | 2000 |
| H Strøm Holding AS | Transport & logistics | 2005 |
| H-B Invest AS | | 2021 |
| Ha-Mer Eiendom AS | Real estate | 2022 |
| Haga Boligutleie AS | Real estate | 2025 |
| Hagen Bolig AS | Real estate | 2021 |
| Hagen Holding AS | Real estate | 2021 |
| Hagtec Invest AS | | 2026 |
| Hagtec Systems AS | Information & communication | 2026 |
| Hair Office AS | Other services | 2024 |
| Halfdansen Transport AS | Transport & logistics | 1993 |
| Hallerud Holding AS | | 2020 |
| Halloien Invest AS | Real estate | 2024 |
| Handshake Norway AS | Wholesale & retail | 2015 |
| Handverk AS | Professional & scientific | 2000 |
| Hanekleiva AS | Real estate | 2018 |
| Hanekleiva Pukkverk AS | Mining & quarrying | 1987 |
| Haning Invest AS | Wholesale & retail | 2005 |
| Havna Brygge AS | Real estate | 2016 |
| Havna Holding Invest AS | Real estate | 2016 |
| HCF Holding AS | | 2023 |
| Heavy Bid AS | Wholesale & retail | 2025 |
| Heksagon AS | Construction | 1997 |
| Helge Bonden Holding AS | Real estate | 2021 |
| Helge Ljøsne AS | Construction | 2000 |
| Helgesen Entreprenørservice AS | Administrative & support | 2023 |
| Hemea Holding AS | | 2021 |
| Henriette & Kristoffer AS | Other services | 2014 |
| Henrik Kjemprud Invest AS | | 2023 |
| Herlofson Invest AS | Real estate | 2017 |
| Hermansen Eiendomsutvikling AS | Real estate | 2021 |
| Hermansen Gartneri Invest AS | Real estate | 2005 |
| Hermansen Gårdsdrift AS | Agriculture & fishing | 2015 |
| Hermansen Maskin AS | Construction | 2006 |
| Heta AS | Wholesale & retail | 1989 |
| HHL Import AS | Wholesale & retail | 2025 |
| Hibiscusreiser AS | Administrative & support | 2010 |
| Hjelps AS | Construction | 2018 |
| Hkbn 4-4 AS | Real estate | 2020 |
| HKBN3 - V3 AS | Real estate | 2020 |
| HMF Holding AS | Financial services | 2005 |
| Holm & Wee Vannverk AS | Water & waste | 1955 |
| Holm Brygge AS | Hospitality | 2004 |
| Holmestrand Bygg AS | Construction | 2022 |
| Holmestrand Fornybar AS | Energy | 2022 |
| Holmestrand Rørservice AS | Construction | 2025 |
| Holmsåsen Vann Og Avløpsselskap SA | Water & waste | 2019 |
| Holtan Bil AS | Administrative & support | 2025 |
| Holtan Corporate Finance AS | | 2025 |
| Holtan Transport AS | Transport & logistics | 2009 |
| Holth Produkter AS | Manufacturing | 2023 |
| Homme Invest AS | | 2020 |
| Horisont Bolig AS | Construction | 2021 |
| Hoven Eiendom AS | Real estate | 2005 |
| Hovland Bilverksted AS | Other services | 2012 |
| Hovsmyra Vann & Avløpslag SA | Water & waste | 2016 |
| HS Anleggservice AS | Construction | 2023 |
| Hsgu Holding AS | | 2018 |
| Hubiz AS | Financial services | 2006 |
| Hverven Begravelsesbyrå AS | Other services | 2022 |
| Hverven Holding AS | Other services | 2022 |
| Hverven Utvikling AS | Real estate | 2024 |
| Hytte Og Hjem Styling AS | Professional & scientific | 2024 |
| Hauger A/S | Manufacturing | 1987 |
| Håheim Holding AS | | 2024 |
| Håve AS | Real estate | 2015 |
| Høydahl Eiendom AS | Real estate | 2024 |
| I-Sikte AS | Information & communication | 2010 |
| Ibe AS | Professional & scientific | 2013 |
| Idrettskoncult AS | Education | 2022 |
| Ima Invest AS | | 2026 |
| Incrementum AS | Financial services | 2018 |
| Ind-Tech AS | Construction | 1996 |
| Ingentellekanter AS | Professional & scientific | 2018 |
| Innregulering AS | Professional & scientific | 2017 |
| Inter-Mont Holding AS | Construction | 2005 |
| Interconcept AS | Professional & scientific | 1988 |
| Interiørhjørnet Da | Wholesale & retail | 2004 |
| Investro AS | Real estate | 1995 |
| Isbaneteknikk AS | Manufacturing | 2022 |
| IT Kompass AS | Information & communication | 2026 |
| ITAVDELING1 AS | Information & communication | 2013 |
| J. C. Grimsrud Transport AS | Construction | 1998 |
| Ja Handel AS | Wholesale & retail | 2023 |
| Jacob Jürgensen Nordic | Administrative & support | 2006 |
| Jam Utvikling AS | Real estate | 2022 |
| Jameco AS | Professional & scientific | 2007 |
| Jbtrading AS | Wholesale & retail | 2010 |
| Jebjørge Holding AS | | 2019 |
| Jelos Invest AS | Construction | 2018 |
| Jensco AS | Construction | 2012 |
| Jil Invest AS | Real estate | 2005 |
| JM Rock Consult AS | Construction | 2017 |
| Johnsrud-Grimsrud Vannledning SA | Water & waste | 1959 |
| Joman AS | Administrative & support | 1993 |
| Judith Johansen AS | Wholesale & retail | 2020 |
| Jørgensen Bil AS | Wholesale & retail | 2017 |
| Jøru Holding AS | Administrative & support | 2007 |