| Harstad Trafikkskole Ans | Education | 2013 |
| Harstad Tørrdokk AS | Manufacturing | 1981 |
| Harstad Ur Og Gull AS | Wholesale & retail | 2017 |
| Harstad Utmarksråd SA | Agriculture & fishing | 2015 |
| Harstad Varme Flis Og Steinsenter AS | Manufacturing | 2019 |
| Harstadbotn Eiendom AS | Transport & logistics | 1998 |
| Harstadbygg Entreprenør AS | Construction | 2006 |
| Harstadbygg Gruppen AS | Real estate | 1986 |
| Harstadhamn Blikkenslagerverksted AS | Construction | 2012 |
| Harstadhamn Psykomotorisk Fysioterapi SA | Health & social care | 2020 |
| HARSTADMESTER1 AS | Construction | 2019 |
| HARSTADTEKKER1 AS | Construction | 2021 |
| Harstadtrippel AS | Arts & recreation | 2025 |
| Hartvik Invest AS | Real estate | 2016 |
| Hatawi AS | | 2023 |
| Haugtussa Finans AS | | 2022 |
| Haukebøe AS | Real estate | 2025 |
| Haukebøe Gis AS | Transport & logistics | 2025 |
| Haukebøe Holding X AS | | 2025 |
| Haukebøe Service AS | Other services | 2023 |
| Haukebøe Transport Gass AS | Transport & logistics | 2024 |
| Haukebøe Transport Tank AS | Transport & logistics | 1986 |
| Haukesyn Holding AS | Wholesale & retail | 2023 |
| Havgapet Holding AS | | 2023 |
| Havnegata 16 Eiendom AS | Real estate | 2020 |
| Havnegata 20 a AS | Real estate | 2017 |
| Havnegata 25 AS | Real estate | 2005 |
| Havnegata 6 AS | Real estate | 2019 |
| Havnegata Lavpris AS | Wholesale & retail | 2016 |
| Havnepaviljongen AS | Real estate | 1991 |
| HBV - Holm Bygg Og Vedlikehold AS | Wholesale & retail | 2023 |
| Heia Naturen AS | Arts & recreation | 2018 |
| Heia Nord-Norge AS | Administrative & support | 2021 |
| Heiben AS | | 2023 |
| Heim Skippen AS | | 2026 |
| Heiofysioterapi AS | Health & social care | 2006 |
| Hele AS | Health & social care | 2012 |
| Helga Lindgården AS | Real estate | 2015 |
| Heli Eiendom AS | Real estate | 1998 |
| Heli Norway AS | Transport & logistics | 2015 |
| Heli Team AS | Transport & logistics | 1988 |
| Hellværing AS | Wholesale & retail | 2017 |
| Helse Helpro AS | Health & social care | 2013 |
| Helsekost Harstad AS | Wholesale & retail | 2017 |
| Hemo Holding AS | Financial services | 2016 |
| Henriksen Maritime Consultancy AS | Professional & scientific | 2017 |
| Hermines Mote AS | Wholesale & retail | 2021 |
| HGB Betong AS | Manufacturing | 2018 |
| HH Holding AS | | 2005 |
| Hindøen AS | | 2024 |
| Hinnstein AS | Professional & scientific | 2005 |
| Hinnøy Elektro AS | Construction | 2020 |
| Hinnøy Maskin AS | Construction | 2006 |
| Hinnøya AS | Real estate | 2024 |
| Hinnøya Renhold AS | Administrative & support | 2016 |
| Hinnøya Travel AS | Administrative & support | 2025 |
| Hinope Invest AS | | 2008 |
| Hitt Elektro AS | Construction | 2021 |
| Hitt Invest AS | Real estate | 2024 |
| Hjerter Dame AS | Wholesale & retail | 2005 |
| Hjørnegården AS | Real estate | 1997 |
| HLG Eiendom AS | Real estate | 2025 |
| HLG Eiendom S7 AS | Real estate | 2024 |
| HM1 Holding AS | Construction | 2019 |
| Hn-Holding AS | Hospitality | 2023 |
| Hob Consulting AS | Professional & scientific | 2025 |
| Hob Eiendom AS | Real estate | 2020 |
| Hob Harstad Sentrum AS | Hospitality | 2024 |
| Hob Kanebogen AS | Hospitality | 1988 |
| Hob Norge AS | Professional & scientific | 2022 |
| Hob Properties AS | Real estate | 2025 |
| Hofsmarken Kiropraktikk Og Helse AS | Health & social care | 2022 |
| Hokland Eiendom AS | Real estate | 1988 |
| Hokland Holding AS | Transport & logistics | 2005 |
| Hokland Marina AS | Wholesale & retail | 2005 |
| Hokland Utvikling AS | Real estate | 2019 |
| Holmen AS | Real estate | 1985 |
| Holmen II AS | Real estate | 2010 |
| Holms Realfagshjelp AS | Education | 2021 |
| Holmsmoker AS | Wholesale & retail | 2012 |
| Holtan Lakså Holding AS | | 2021 |
| Holtet Barnehage SA | Education | 1993 |
| Hoochie Mama Enterprises Da | Arts & recreation | 2022 |
| Hotel Arcticus AS | Hospitality | 1999 |
| Hotell Kaarbø AS | Real estate | 2018 |
| Hotell Lofoten AS | Hospitality | 1974 |
| Hotelldrift Q Harstad AS | Hospitality | 1985 |
| Hotelleiendom Nord AS | Real estate | 2019 |
| House of Nilsen Ltd Nuf | Administrative & support | 2017 |
| Houz Invest AS | | 2020 |
| HPS Consulting AS | Arts & recreation | 2015 |
| HRH Revisjon AS | Professional & scientific | 1998 |
| HRS Metallco AS | Water & waste | 1995 |
| HRS Metallco Eiendom Tromsø AS | Real estate | 2009 |
| HS Invest AS | Real estate | 2014 |
| Hs-Eiendom AS | Real estate | 2017 |
| HSP Kapital AS | | 2026 |
| Hugo's Renseri Og Vaskeri AS | Other services | 2001 |
| Humankraft AS | Health & social care | 2012 |
| Huubro AS | Information & communication | 2019 |