| Ias AS | | 2016 |
| Ilevanger AS | Information & communication | 2020 |
| Imellom AS | Education | 2019 |
| Indal Okkenhaug Maskinlag SA | Construction | 2017 |
| Indgaard Samdrift Da | Agriculture & fishing | 1998 |
| Induform AS | Manufacturing | 1975 |
| Ingas Holding AS | | 2024 |
| Ingeniørgården AS | Real estate | 2012 |
| Ingvaldsen Eiendom AS | Real estate | 2018 |
| Ingvaldsen Holding AS | | 2025 |
| Innherred Aesthetics AS | Health & social care | 2026 |
| Innherred Bolig AS | Real estate | 2026 |
| Innherred Bygginvest AS | Real estate | 2005 |
| Innherred Eiendom AS | Professional & scientific | 1988 |
| Innherred Entreprenør AS | Construction | 2016 |
| Innherred Helsehus AS | Health & social care | 2013 |
| Innherred Håndverktjenester Iht AS | Real estate | 2017 |
| Innherred Idrettsmedisin AS | Health & social care | 2015 |
| Innherred Kirurgi AS | Health & social care | 2017 |
| Innherred Kvinneklinikk AS | Health & social care | 2025 |
| Innherred Ultralydklinikk AS | Health & social care | 2021 |
| Innherred Utvikling AS | Real estate | 2000 |
| Innherred Øyeklinikk AS | Health & social care | 2014 |
| Innherredsferja AS | Transport & logistics | 1957 |
| Innherredsveien 71 AS | Real estate | 2022 |
| IOT2B Consult AS | Professional & scientific | 2024 |
| Isa Electro Mind AS | Financial services | 2010 |
| Iswa AS | | 2026 |
| J Alstad Maskin AS | Construction | 2026 |
| J K E Design Levanger AS | Wholesale & retail | 2005 |
| Jbgt 27 AS | Real estate | 2010 |
| Je Prosessmontasje AS | Manufacturing | 2023 |
| Jeca Invest AS | Agriculture & fishing | 2005 |
| Jernbanegata 21 AS | Real estate | 2007 |
| Jle AS | Transport & logistics | 2022 |
| Jle Grunnforsterkning AS | Construction | 2016 |
| Jle Holding AS | Construction | 2022 |
| Joaa AS | Real estate | 2015 |
| Joanso Da | Hospitality | 2001 |
| Jonas Bil AS | Other services | 2023 |
| Jonas Sivertsen Holding AS | Manufacturing | 2018 |
| Joplassvegen 6 AS | Real estate | 2020 |
| Jordbærpikene Levanger AS | Hospitality | 2012 |
| Jordfabrikken AS | Manufacturing | 2002 |
| Joval Eiendom AS | Real estate | 2024 |
| Jowo AS | Professional & scientific | 2019 |
| K Vest AS | Real estate | 2020 |
| K4 Invest AS | Real estate | 2004 |
| K4 Kultur AS | Administrative & support | 2016 |
| K4 Maritim AS | Wholesale & retail | 2020 |
| K4 Næring AS | Real estate | 2008 |
| K4 Åsen AS | Real estate | 2007 |
| Kaisa Holding AS | | 2023 |
| Kardiolog Skjetne AS | Health & social care | 2020 |
| Karlsen Urologi AS | Health & social care | 2024 |
| Karma Frisør & Velvære AS | Other services | 2020 |
| Karstad Bygg AS | Construction | 2026 |
| Katro Eiendom AS | Real estate | 2012 |
| Kayenne Express AS | Hospitality | 2024 |
| KBF Holding AS | | 2021 |
| KG Event AS | Arts & recreation | 2025 |
| KGT46 AS | Real estate | 2025 |
| Kim Ståle Bjørgen Holding AS | Professional & scientific | 2022 |
| Kir 57 AS | Real estate | 2002 |
| Kirkegata 26 AS | Real estate | 2016 |
| Kirkegata 47 AS | Real estate | 2022 |
| Kirkegata 55 AS | Real estate | 2021 |
| Kirkegata 75 AS | Real estate | 2018 |
| Kirkegata Legesenter AS | Health & social care | 2023 |
| Kirkegaten 31 Restaurant AS | Hospitality | 2018 |
| KIRO1 AS | Health & social care | 1998 |
| KIRO1 Holding AS | Health & social care | 2005 |
| Kiropraktor Sørli AS | Health & social care | 2014 |
| Kjell's Eiendom AS | Real estate | 2005 |
| Kjærlighetsstien Bolig AS | Real estate | 2021 |
| Kjøkkenfornyelse Midt-Norge AS | Wholesale & retail | 2020 |
| Kjølåsen Maskinlag SA | Agriculture & fishing | 1983 |
| Klas AS | Construction | 1985 |
| Klippet & Klart AS | Information & communication | 2018 |
| Klubbhuset Moan AS | Real estate | 2024 |
| Klubbnett AS | Wholesale & retail | 2014 |
| KM Technics AS | Other services | 2004 |
| Kollektiv Boligforvaltning AS | Real estate | 2011 |
| Kommunal Gjeld AS | Professional & scientific | 2007 |
| Kompis Levanger AS | Hospitality | 2022 |
| Komplettnettbutikk.No AS | Information & communication | 2017 |
| Konstant AS | Information & communication | 2011 |
| Krifos AS | Real estate | 2011 |
| Kristine Skjetne AS | Health & social care | 2018 |
| Kriz Me Zanz AS | Wholesale & retail | 2010 |
| Krofin AS | | 1999 |
| Kvam Agentur AS | Administrative & support | 2002 |
| Kvam Agentur Eiendom AS | Real estate | 2007 |
| Kvello Castrum AS | Real estate | 2006 |
| Kverkild Eiendom AS | Real estate | 2020 |
| Kvilstadvegen 8O-P AS | Real estate | 2025 |
| Kvitvang Fjellsprengning AS | Construction | 2013 |
| Kværnø Sko Levanger AS | Wholesale & retail | 1999 |
| LAA24 AS | Real estate | 2017 |
| Langroa Invest AS | Real estate | 1992 |