| A.L Auto AS | Wholesale & retail | 2025 |
| Aaen Holding AS | | 2024 |
| Abeka Eiendom AS | Real estate | 2010 |
| Abiecare AB Nuf | Health & social care | 2015 |
| Ace Klær Ans | Wholesale & retail | 2009 |
| Alvdal Graveservice AS | Construction | 2005 |
| Alvdal-Tynset Sport AS | Wholesale & retail | 1980 |
| Amdo AS | Health & social care | 2022 |
| Ams-Eiendom AS | Real estate | 2026 |
| Anders Stormoen AS | Construction | 2019 |
| André Enget Holding AS | Real estate | 2022 |
| Anleggsrep AS | Administrative & support | 1997 |
| Apri AS | Professional & scientific | 2025 |
| Army & Outdoor AS | Wholesale & retail | 2017 |
| Arvid Vangen AS | Transport & logistics | 2015 |
| Auma Tanktransport AS | Transport & logistics | 2004 |
| Auma Vannverk SA | Water & waste | 1950 |
| Aumdalen Grunneierlag SA | Real estate | 1951 |
| Autoassistanse Tynset AS | Transport & logistics | 2010 |
| Autoskade Tynset AS | Other services | 2012 |
| Avineering AS | Construction | 2017 |
| Avineering Solutions AS | Professional & scientific | 2024 |
| Aviva Eiendom AS | Real estate | 2017 |
| Aviva Holding AS | Real estate | 2017 |
| Avløserkortet AS | Information & communication | 2026 |
| Back to Basic Hår Og Fot AS | Health & social care | 2019 |
| Bakker Holding AS | Real estate | 2004 |
| Bakstadgutane AS | Construction | 2018 |
| Baleci Eiendom AS | Real estate | 2024 |
| Bauer Rør Og Bad AS | Construction | 2026 |
| Beauty Land AS | Other services | 2024 |
| Bedriftshelsetjeneste AS | Health & social care | 1990 |
| Bekkevoll Bygg Invest AS | | 2019 |
| Bellingan Holding AS | Construction | 2024 |
| Berkåk Energi- Og Næringspark AS | Professional & scientific | 2023 |
| BHD Holding AS | | 2023 |
| Biggen Holding AS | | 2026 |
| Bilfinn Eiendom AS | Wholesale & retail | 2017 |
| Bilfinn Nuf | Wholesale & retail | 2010 |
| Bilskadesenteret Tynset AS | Other services | 2006 |
| Bilskadesenteret Tynset Holding AS | | 2026 |
| Bjørn Lermoen Holding AS | Construction | 2022 |
| Blae Holding AS | Manufacturing | 2022 |
| Blomsterteltet Tynset AS | Wholesale & retail | 2019 |
| Blomstertunet Tynset AS | Wholesale & retail | 2019 |
| Bnø Eiendomsutvikling AS | Real estate | 2017 |
| Bnø Holding AS | Construction | 2011 |
| Bohus Tynset AS | Wholesale & retail | 2014 |
| Bondåsen-Moanlia Sankelag SA | Agriculture & fishing | 1995 |
| BOOK1 Trysil AS | Administrative & support | 2018 |
| Brekka Boliggrend AS | Real estate | 2025 |
| Brekken-Ripan Grunneierlag SA | Agriculture & fishing | 1933 |
| Bris Frisør Tynset AS | Other services | 1994 |
| Bris Tynset AS | Other services | 2025 |
| BRN Service AS | Administrative & support | 2025 |
| Bronkemoen Solcellekraftverk AS | Energy | 2022 |
| Brugata 14B AS | Real estate | 2004 |
| Brødrene Harsjøen Entreprenør AS | Construction | 2020 |
| Brødrene Mælen Maskin Og Landbruk AS | Manufacturing | 2012 |
| Buron Transportservice AS | Transport & logistics | 2024 |
| Byggservice Nord-Østerdal AS | Construction | 1998 |
| Byvold Investments AS | | 2021 |
| Ceriwest Publishing AS | Information & communication | 2025 |
| CF Maskin Tunna Auto AS | Other services | 2011 |
| Cfmoto Senteret AS | Wholesale & retail | 2021 |
| Chili Frisørteam AS | Other services | 2014 |
| Chovan AS | Information & communication | 2026 |
| Coysa Holding AS | Health & social care | 2016 |
| Cozmo AS | Wholesale & retail | 2005 |
| D&R Tynset Bilvask Og Service AS | Other services | 2020 |
| Dahlstrøen Holding AS | | 2022 |
| Dalsegg Rørleggerservice AS | Construction | 2013 |
| Demring Al | Real estate | 1927 |
| Det Lille Ekstra Design | Manufacturing | 2006 |
| Diesel Norge AS | Wholesale & retail | 1991 |
| Eggen Barnehage SA | Education | 1997 |
| Eloc AS | Wholesale & retail | 2013 |
| Eltron AS | Construction | 1982 |
| Energima Fjellregionen AS | Construction | 2021 |
| Energipluss AS | Energy | 2017 |
| Energiøkonomisering AS | Professional & scientific | 2015 |
| Engetøve Samdrift Da | Agriculture & fishing | 2006 |
| Eriksen Consulting Tynset AS | Professional & scientific | 2024 |
| Esta AS | Construction | 2024 |
| Feh Holding AS | Financial services | 2018 |
| Finstadlavvoen AS | Construction | 2016 |
| Fjellfrukt AS | Wholesale & retail | 2025 |
| Fjellmøkk SA | Manufacturing | 2026 |
| Fjellpukk AS | Mining & quarrying | 2011 |
| Fjellregion Eiendom AS | Real estate | 2017 |
| Fjellregionen Berging AS | Transport & logistics | 2023 |
| Fjellregionen Renhold AS | Administrative & support | 2020 |
| Fjellugla Kompetanse AS | Education | 2010 |
| Flaten Bil AS | Wholesale & retail | 2012 |
| Flax Eiendomsutvikling AS | Real estate | 2005 |
| Frak AS | Other services | 2008 |
| Frislid & Sønn AS | Real estate | 2024 |
| Fron Traktor Service Tynset AS | Wholesale & retail | 2022 |
| Fådal Bygg AS | Construction | 2013 |
| Fådal Jakt Og Fiske SA | Arts & recreation | 2012 |