| Intakt Midt AS | Trondheim | 2020 |
| Intarsia AS | Søreidgrend | 2025 |
| Intec UK Ltd | Ianshire La3 2Z | 2013 |
| Intecom AS | Trondheim | 2019 |
| Intecture Consulting BV | Nl.1012 Hl Amsterdam | 2019 |
| Integra Sikkerhet AS | Oslo | 2022 |
| Intellika AS | Oslo | 2005 |
| Intelliserv LLC | 84606 Provo Utah | 2015 |
| Intellitix Technologies Inc. | Ca - Montreal H3C 2Mi | 2018 |
| Intense AS | Fjellhamar | 1998 |
| Intense Productions AS | Oslo | 2019 |
| Inteo Utleie AS | Vatne | 2023 |
| Inteprof Da | Sandnes | 2002 |
| Inter Fjernsyn Da | Bergen | 2000 |
| Inter Gruppen AS | Haugesund | 2020 |
| Inter Marine Spolka Z Ograniczona Odpowiedzialnoscia Nuf | Pl-81-578 Gdynia | 2024 |
| Inter Nordisk Rent Ans | Brønnøysund | 2006 |
| Inter Svets AB | 461 34 Trollhettan | 2001 |
| Inter Travel Sport & Event AS | Oslo | 2009 |
| Interactive People AS | Kleppestø | 2018 |
| Interbauhaus Leasing AG | Lierskogen | 2008 |
| Interbox-Tak Og Fasadevask | Trondheim | 2003 |
| Intercreative AS | Mjøndalen | 2013 |
| Interex Limited Nuf | London Ec2M 2Ef England | 2026 |
| Interflora Norge SA | Billingstad | 1975 |
| Intergaph Espana | 28023 Madrid | 2015 |
| Intergraph Pp&M Deutchland GmbH | Asker | 2014 |
| Interim Norge AS | Asker | 2016 |
| Interim Norge Holding AS | Asker | 2016 |
| Interkulturelt Samvirke Ik SA | Oslo | 2024 |
| Interlog AS | Hagan | 2016 |
| Intermoor AS | Stavanger | 1994 |
| Intermoor Limited | Aberdeen Ab23 8Jx | 2008 |
| Intern Utleie AS | Trøgstad | 2022 |
| Internasjonal Tours AS | Oslo | 2006 |
| Internasjonale Messetjenester AS | Jessheim | 2010 |
| International Baccalaureate Organization | Ch-1202 Geneve | 2024 |
| International Bar Association | New York 12205 | 2025 |
| International Congress and Convention Association (Icca) | 1101Bh Amsterdam | 2016 |
| International Consulting Services AS | Kolbotn | 1994 |
| International Corporate Art AS | Oslo | 1989 |
| International Marine Services Ltd. | St. John'S Newfoundland A1A 5G9 | 2012 |
| International Maritime Management | Fo-700 Klaksvik | 2012 |
| International Oilfield Services AS | Stavanger | 1987 |
| International Professional Resources (Europe) B.V. | Nl-3001Hc Rotterdam | 2012 |
| International Professional Resources (Us) Limited | Dubai Uae | 2012 |
| International Professional Resources Limited | Dubai | 2003 |
| International Sos Mea Fzco | Dubai | 2022 |
| International Trade & Exhibitions (JV) Ltd | London Nw6 6Rg England | 2013 |
| International Training Equipment Conference Limited | London Se17Tl England | 2024 |
| Internet Elephants Ltd | London W1H 6Hn | 2015 |
| Intero Integrity Services B.V. | 4196 Hg Tricht | 2015 |
| Interocean Personnel Services BV | 2909Lk Capelle Aan Den Ijssel | 1996 |
| Interoil Exploration and Production ASA | Oslo | 2005 |
| Interoil Peru Holding AS | Oslo | 2011 |
| Interpersonell AS | Asker | 2006 |
| Interrent AS | Gardermoen | 2014 |
| Interstral (Norway) Limited | London Ec1V 2Nx England | 2024 |
| Interstuhl Büromöbel GmbH & Co. KG Nuf | De-72469 Meßstetten - Tieringen | 2025 |
| Intertrust (Spain) S.L.U | Es 28001 Madrid | 2016 |
| Intervenio Nuf | Se-724 82 Västerås | 2023 |
| Intervista AS | Oslo | 2015 |
| Inti Ren AS | Skien | 2021 |
| Into Nature AS | Meistervik | 2024 |
| Into the Fjords AS | Paradis | 2020 |
| Intracon AS | Maura | 1988 |
| Intronic AS | Oslo | 2018 |
| Intrum AS | Lysaker | 1984 |
| Intrum Holding Norway AS | Lysaker | 2008 |
| Intrum Obligations AS | Lysaker | 1987 |
| Intunor Finance AS | Oslo | 2016 |
| Inuvdal Holding AS | Uvdal | 2022 |
| Inuvdal Hytteservice AS | Uvdal | 2021 |
| Inventron AS | Oslo | 2002 |
| Inventum Event AS | Haugesund | 2020 |
| Invest + AS | Fåvang | 2007 |
| Invest in Norway AS | Oslo | 2019 |
| Invest Øst AS | Ottestad | 2002 |
| Investa Kapital AS | Drammen | 2024 |
| Investfjord Drift AS | Stamsund | 2021 |
| Investida AS | Trondheim | 2025 |
| Investment Du Nord AS | Oslo | 1987 |
| Investo 24 AS | Sandnes | 2021 |
| Investor Kapital AS | Gullaug | 1995 |
| Investorforum Nordmøre AS | Kristiansund N | 2012 |
| Investorprosjekt 456 AS | Oslo | 2024 |
| Investrheim Holding AS | Bergen | 2022 |
| Inyai Renhold AS | Longyearbyen | 2023 |
| Io Byggservice AS | Ålesund | 2021 |
| Ioefive Network (Norway) Limited | London Ec1V 2Nx England | 2024 |
| Ion International Sarl | Dubai | 2012 |
| Ionian Seil AS | Oslo | 2025 |
| Iotera AS | Ålesund | 2025 |
| IP Care AS | Harstad | 2023 |
| IP Gruppen AS | Tomasjord | 2023 |
| IP Norway AS | Åmot | 2008 |
| IP Teknikk Industry AS | Dale I Sunnfjord | 2026 |
| IP Teknikk Service AS | Dale I Sunnfjord | 2023 |
| Ipaddle AS | Paradis | 2022 |
| Ipco Ipr AS | Kokstad | 2019 |