| Ok Kristoffersen Holding AS | Construction | 2022 |
| Oluf Eiendom AS | Real estate | 2002 |
| Op. Eiendom AS | Real estate | 2026 |
| Osom Apps AS | Real estate | 2016 |
| Otaku Diner AS | Hospitality | 2020 |
| Outmove AS | | 2022 |
| Ottar Kristoffersen Eftf. AS | Real estate | 1970 |
| Paul Venås AS | Health & social care | 2021 |
| Pihoqahiak AS | Arts & recreation | 2023 |
| Princilla AS | | 2019 |
| Procx Offshore Consult AS | Professional & scientific | 2025 |
| Publiners Da | Arts & recreation | 2001 |
| Rab Holding AS | Professional & scientific | 2009 |
| Rainbow Nord Kundetjeneste AS | Other services | 1999 |
| Rasa Capital AS | | 2020 |
| RCN Holding AS | | 2026 |
| Regnskapssentret AS | Professional & scientific | 1988 |
| Reiersen & Berger AS | Construction | 2005 |
| Reis & Nyt Sør-Helgeland SA | Administrative & support | 2025 |
| Reizer Solutions AS | Information & communication | 2025 |
| Relakk Motor & Karosseri AS | Other services | 2004 |
| Ringveien Eiendom AS | Real estate | 2022 |
| RJ Landbrukstjenester AS | Administrative & support | 2024 |
| Rock Media AS | Information & communication | 2021 |
| Rugåshylla Eiendom AS | Real estate | 2021 |
| Rødli Rørservice AS | Construction | 2018 |
| Rørmark Rør Og Varme AS | Construction | 2020 |
| Saho Invest AS | | 2022 |
| Salhus Eiendom AS | Real estate | 2005 |
| Salhus Tomteselskap AS | Real estate | 2013 |
| Salhusmarka Holding AS | Real estate | 2013 |
| Salhusramp AS | Wholesale & retail | 2023 |
| Salhussletta AS | Real estate | 2011 |
| Sanfe 52 AS | Real estate | 2022 |
| Sannas Eiendom AS | Real estate | 2008 |
| Sarhuset AS | Real estate | 2022 |
| Saturn Invest AS | Transport & logistics | 2005 |
| SBS Teknikk Eiendom AS | Real estate | 2018 |
| Sea to Sky AS | Administrative & support | 2025 |
| Seafun Boat Da | Manufacturing | 2003 |
| Sen Invest AS | Real estate | 2005 |
| Sentrum Bygg Og Eiendom AS | Real estate | 2020 |
| Shha Eiendom AS | Real estate | 2011 |
| Shha Holding AS | Manufacturing | 2018 |
| Sigleif Mork AS | Wholesale & retail | 1993 |
| Silkefabrikken AS | Real estate | 1997 |
| Sina Holding AS | Agriculture & fishing | 2021 |
| Sinus Brønnøysund AS | Construction | 1989 |
| Sjøfisk & Rorbuer AS | Agriculture & fishing | 2018 |
| Sjøstua AS | Real estate | 2022 |
| SK Solutions AS | Administrative & support | 2025 |
| Sklinnabanken AS | Agriculture & fishing | 2002 |
| Skogmo Familiecamping AS | Hospitality | 2018 |
| SM Berger Holding AS | | 2025 |
| SM Holding AS | Wholesale & retail | 2005 |
| Smakmix Grill & Kiosk AS | Hospitality | 2025 |
| Smedvika Eiendom AS | Real estate | 2023 |
| SN Nord AS | Real estate | 2015 |
| SN Sør AS | Real estate | 2013 |
| SN Vest AS | Real estate | 2013 |
| Snekker Fredriksen AS | | 2013 |
| Snekker Johnsen AS | Construction | 2023 |
| Soleng Eiendom AS | Real estate | 2025 |
| Soltun Barnehage SA | Education | 1990 |
| Som Spikra AS | Construction | 2023 |
| Sommertune Forsk. AS | Real estate | 2015 |
| Spacefish AS | | 2022 |
| Spacefish Elfro AS | | 2025 |
| SPB AS | Construction | 2022 |
| SPB Eiendom AS | Real estate | 2022 |
| SPB Investment AS | Construction | 2022 |
| SPB Transport AS | Transport & logistics | 2020 |
| Sport 1 Brønnøysund AS | Wholesale & retail | 2021 |
| ST1 Holding AS | | 2021 |
| Stakstøn Lyd, Lys & Event Da | Arts & recreation | 2008 |
| Stege AS | Real estate | 2010 |
| Stetind Entreprenør AS | Construction | 2020 |
| Stine Marlén AS | Wholesale & retail | 2025 |
| Storgata 2 Eiendom AS | Real estate | 2022 |
| Storgata 70 AS | Real estate | 1998 |
| Storgaten 74-76 Brønnøysund AS | Other services | 2015 |
| Storgt. 73 AS | Real estate | 1972 |
| Stortoft AS | | 2021 |
| Stærsk Trimsenter AS | Arts & recreation | 2022 |
| Svang Catering AS | Hospitality | 2017 |
| Sylteren Barnehage SA | Education | 1990 |
| Syltern Bygg Eiendom AS | Real estate | 2013 |
| Syltern Bygg Og Rehabilitering AS | Construction | 2000 |
| Sør Helgeland Nødslaktservice AS | Manufacturing | 2010 |
| Sør-Helgeland Eiendom AS | Real estate | 1995 |
| Sør-Helgeland Holding AS | Professional & scientific | 2022 |
| Sør-Helgeland Vaktselskap AS | Administrative & support | 2000 |
| Søren Nielsen Eiendom AS | Real estate | 2005 |
| Sørneset Produksjon AS | Information & communication | 2015 |
| Søren Nielsen AS | Real estate | 1924 |
| T.Brønmo AS | Construction | 2022 |
| Ta Karlsen AS | Administrative & support | 2024 |
| Takst-Forum Helgeland AS | Real estate | 2026 |
| Tannboden Brønnøysund AS | Health & social care | 2010 |
| Tannlege Maria Valan AS | Health & social care | 2025 |