| Harbour Howff Ltd | Kirkcaldy Ky1 2Sn Scotland | 2018 |
| Harburg AS | Østerås | 2005 |
| Harby Prosjektstyring AS | Hamar | 2021 |
| Harcon AS | Ålesund | 2007 |
| Hard Work AS | Oslo | 2015 |
| Hard-Tech AS | Tørvikbygd | 2012 |
| Hardanger Consulting AS | Øystese | 2001 |
| Hardanger Data Og Reklame Da | Kinsarvik | 1996 |
| Hardanger Dyreklinikk AS | Odda | 2000 |
| Hardanger Elektro AS | Odda | 2014 |
| Hardanger Hydrogen Hub AS | Odda | 2024 |
| Hardanger Media AS | Øystese | 2023 |
| Hardanger Og Voss Næringshage AS | Voss | 2013 |
| Hardanger Rekneskap SA | Øystese | 1983 |
| Hardanger Revisjon AS | Øystese | 2020 |
| Hardanger Takst Og Konsulenttjenester AS | Odda | 2022 |
| Hardbaken Holding AS | Hamresanden | 2008 |
| Hardbarka AS | Manger | 2007 |
| Harder AS | Harstad | 2010 |
| Hardertek AS | Drammen | 2015 |
| Hardetklart AS | Stavanger | 2022 |
| Hardex AS | Knarrevik | 2016 |
| Hardfør AS | Konsmo | 2019 |
| Hardfør Utvikling AS | Harstad | 2025 |
| Harding Eiendom AS | Grimstad | 2016 |
| Harding Invest AS | Oslo | 2004 |
| Hardinges Consultans Limited | London W1H 1Pj England | 2017 |
| Hardingtakst AS | Øystese | 2015 |
| Hardlife AS | Kleppestø | 2012 |
| Hardrada AS | Oslo | 2026 |
| Hardt Betonginteriør Da | Åros | 2017 |
| Hardwoods AS | Askim | 2013 |
| Hardworking AS | Sundebru | 2020 |
| Hareide Design AS | Moss | 1999 |
| Hareima AS | Sunndalsøra | 2025 |
| Hareland Engineering AS | Sola | 1991 |
| Harestua Dyreklinikk AS | Harestua | 2020 |
| Harg Work AS | Høvik | 2026 |
| Hargau AS | Larvik | 2015 |
| Haric AS | Sørreisa | 2017 |
| Hariko AS | Kleppe | 2015 |
| Hark AS | Oslo | 2016 |
| Hark Technologies AS | Oslo | 2016 |
| Harkand Global Holdings Limited | London W6 8Dl England | 2015 |
| Harlem Capital AS | Borgen | 2017 |
| Harlem Kommunikasjon AS | Haslum | 2012 |
| Harlow Tse Norge | Essex C09 2Sz | 2024 |
| Harlun Holding AS | Skien | 2021 |
| Harmo AS | Drammen | 2005 |
| Harmoni Regnskap AS | Oslo | 2025 |
| Harmonisk Business AS | Skien | 2025 |
| Harness Energy Limited Nuf | Dundee Dd1 1Rq | 2019 |
| Haro Interiør AS | Sjøvegan | 2005 |
| Haro Marketing AS | Egersund | 2006 |
| Harold Investment AS | Stavanger | 2016 |
| Harold Sletten Consulting AS | Bergen | 2013 |
| Harold Tellez Sivilarkitekter AS | Oslo | 2025 |
| Harper Film AS | Henningsvær | 2019 |
| Harpercollins Nordic AB | Se-10247 Stockholm | 1997 |
| Harpers Development AS | Hamar | 2024 |
| Harpers Holding AS | Hamar | 2023 |
| Harri Lahtinen Consulting Limited | Colchester Co2 8Uu | 2013 |
| Harridsleff Bygg & Eiendom AS | Halden | 2016 |
| Harris Advokatfirma AS | Bergen | 2018 |
| Harris Engineering Consultants Limited | Ch5 4Fd Flintshire | 2016 |
| Harris Pye Scandinavia | Dk-9400 Nørresundby | 2013 |
| Harris Pye United Kingdom Limited | Cf63 4Ab Vale Of Glamorgan | 2013 |
| Harry AS | Oslo | 2020 |
| Harsco Infrastructure Services GmbH | De-40855 Ratingen | 2011 |
| Harstad Finans AS | Harstad | 1996 |
| Harstad Invest AS | Storsteinnes | 2000 |
| Harstad New Energy AS | Harstad | 2000 |
| Harstad Sentrum AS | Harstad | 2019 |
| Harstad Takst AS | Harstad | 2012 |
| Harstadbotn Dyreklinikk AS | Tromsø | 2021 |
| Hart D.C. Survey Ltd | Gb-Ky12 9Eg Dunfermline | 2018 |
| Harteig AS | Reistad | 1996 |
| Hartek AS | Oslo | 2018 |
| Hartford Hall Engineering Services Ltd | Northumberland Ne22 5Ab | 2020 |
| Hartley Ventures AS | Oslo | 2024 |
| Hartmann Arkitekter AS | Asker | 2004 |
| Hartmann Prosjektrådgivning AS | Trondheim | 2010 |
| Hartmanns Norge AS | Oslo | 2015 |
| Hartmark Executive Search AS | Oslo | 2007 |
| Harto Regnskapsrådgivning Nuf | Bekkestua | 2004 |
| Hartor Limited | Glasgow G3 6Aa Scotland | 2016 |
| Hartvig Wennberg AS | Oslo | 1996 |
| Hartz K G Holding AS | Åmot | 2019 |
| Hartz Ressurs AS | Åmot | 2020 |
| Harudes Holdings AS | Nyborg | 2019 |
| Harunda AS | Tjøme | 2006 |
| Harung Invest AS | Høvik | 1989 |
| Harv Invest AS | Kristiansand S | 2015 |
| Harvest Geo AS | Tolvsrød | 2017 |
| Harvester Asset Management AS | Bodø | 2018 |
| Harvish AS | Rådal | 2024 |
| Harwest AS | Oslo | 2019 |
| Harøy Regnskap AS | Harøy | 2023 |
| Has Architects AS | Oslo | 2022 |
| Has AS | Bergen | 2005 |