| Polarkonsult AS | Professional & scientific | 1976 |
| Portinord AS | Wholesale & retail | 2020 |
| Portveien Barnehage Da | Education | 1989 |
| Postgården Harstad AS | Wholesale & retail | 2004 |
| Prae AS | Professional & scientific | 2017 |
| Praksislære Ved Vågsfjord Legesenter AS | Health & social care | 2024 |
| Precuro AS | Health & social care | 2013 |
| Preg Harstad AS | Real estate | 2006 |
| Preget Av Blomsø AS | Hospitality | 2024 |
| Pricom AS | Information & communication | 1991 |
| Prime Da | Arts & recreation | 1999 |
| Pro Sales Holding Ans | Administrative & support | 1999 |
| Proffice Nor AS | | 2022 |
| Profilio Da | Professional & scientific | 2024 |
| Propellen AS | Real estate | 2019 |
| Proservice AS | Transport & logistics | 2026 |
| PRS Holding AS | Real estate | 2006 |
| Pryd Av Capelli AS | Other services | 2015 |
| PSM Eiendom AS | Real estate | 2013 |
| Psykolog Carl Fredrik Gamst AS | Health & social care | 2003 |
| Psykolog Jørn H.Grønvold AS | Health & social care | 2019 |
| Psykologspesialist Lisa Kristin Nielsen AS | Health & social care | 2026 |
| Psykologspesialist Ranie Torsfred AS | Health & social care | 2018 |
| Pure Presteng AS | Information & communication | 2024 |
| Qualitet Bygg AS | Construction | 2026 |
| Quartz Factory AS | Mining & quarrying | 2011 |
| R a S Holding AS | Administrative & support | 2020 |
| R. Enoksen Holding AS | | 2019 |
| Ragle Holding AS | Transport & logistics | 2023 |
| Ragnhild Strøm AS | Other services | 2017 |
| Ragnhilds Hundeklipp AS | Agriculture & fishing | 2019 |
| Raian Holding AS | | 2022 |
| Rami Bygg AS | Construction | 2021 |
| Ramu AS | Professional & scientific | 2017 |
| Rasmussen Eiendom Grøta AS | Real estate | 2017 |
| Raus Frisørene AS | Other services | 2022 |
| RB1 Holding AS | | 2023 |
| Rebygg AS | Construction | 2021 |
| Regnbuen Hårsenter AS | Other services | 1988 |
| Reh Holding AS | | 2025 |
| Rehabsport AS | Health & social care | 2023 |
| Rein Visuals AS | Professional & scientific | 2023 |
| Rek - Mont AS | Professional & scientific | 2005 |
| Rekt AS | Wholesale & retail | 2014 |
| RELATION04 Media AS | Information & communication | 2004 |
| Renova AS | Professional & scientific | 2003 |
| Reppen Vaktmesterservice Ans | Administrative & support | 1995 |
| Resam AS | Professional & scientific | 2026 |
| Restaurant Milano Da | Hospitality | 2001 |
| Rettinvest AS | | 2025 |
| Revigo AS | Professional & scientific | 1995 |
| Revigo Holding AS | Professional & scientific | 2022 |
| RF Holding Harstad AS | | 2021 |
| RFM Invest AS | Financial services | 2007 |
| RH Bil AS | Wholesale & retail | 2005 |
| RH Bygg Invest | | 2023 |
| Rhlm Holding AS | | 2022 |
| Rib Harstad AS | Arts & recreation | 2026 |
| Riban Invest AS | | 2020 |
| Ridderseth AS | Administrative & support | 2021 |
| Ridderseth Eiendom AS | Real estate | 2025 |
| Ridderseth Rekruttering AS | Administrative & support | 2025 |
| Rik. Kaarbøs GT. 9 AS | Real estate | 2000 |
| Rikard Kaarbøsgate 11 AS | Real estate | 2013 |
| Rino Grande Holding AS | Real estate | 2006 |
| Risge AS | Education | 2023 |
| Risholmbukt AS | Administrative & support | 2018 |
| Risnes Økonomi AS | Financial services | 2010 |
| Rixn Holding AS | | 2022 |
| RJW Eiendom AS | Real estate | 2022 |
| RJW Holding AS | Real estate | 1995 |
| RM Eiendom AS | Wholesale & retail | 2004 |
| Rmo Invest AS | Financial services | 2017 |
| Roaldsen Eiendom AS | Real estate | 2018 |
| Roaldsen Holding AS | Agriculture & fishing | 2018 |
| Rock AS | Manufacturing | 2016 |
| Rofosn AS | Agriculture & fishing | 2023 |
| Roger Rørinspeksjon AS | Professional & scientific | 2003 |
| Rognerud Bygg & Takst AS | Construction | 2008 |
| Rognerud Holding AS | Administrative & support | 2018 |
| Rognerud Utleie AS | Administrative & support | 2018 |
| Rola Eiendom AS | Real estate | 2021 |
| Rola Eiendom Ltd Nuf | Real estate | 2008 |
| Rolf Olsen Consulting AS | Professional & scientific | 2010 |
| Rolness Helse & Trening AS | Arts & recreation | 2015 |
| Rom Te Alt AS | Real estate | 2020 |
| Ronmel AS | Administrative & support | 2007 |
| Rool Holding AS | Manufacturing | 2017 |
| Roomi AS | Real estate | 2019 |
| Rorhusvegen Invest AS | | 2005 |
| Rosini AS | Real estate | 1982 |
| Rs-Eiendomsverdi AS | Professional & scientific | 2013 |
| RSH Invest AS | Financial services | 2010 |
| RT Holding Harstad AS | | 2021 |
| RTK AS | Professional & scientific | 2006 |
| Ruggevik AS | Construction | 2013 |
| Ruggevikveien 17 AS | Real estate | 2008 |
| Rundhågen 1 AS | Real estate | 2007 |
| Rune Holmgren AS | | 2023 |
| Rungfa Thai Food AS | Hospitality | 2011 |