| Krosbyfjerdingen Utmarkslag SA | Real estate | 1981 |
| Linjalen AS | Professional & scientific | 2019 |
| Live Work Consult AS | Professional & scientific | 2012 |
| LKM 1 AS | Real estate | 2005 |
| LS Elektro AS | Construction | 2024 |
| Løken Trevare A/S | Manufacturing | 1988 |
| Malermester Studsrud AS | Construction | 1998 |
| Manoy Consult AS | Professional & scientific | 2018 |
| Marianne Aadalen AS | Professional & scientific | 2005 |
| Marker Anlegg AS | Construction | 2009 |
| Marker Dekk Og Bilpleie AS | Other services | 2021 |
| Marker Eiendomsutvikling AS | Real estate | 2000 |
| Marker El-Installasjon AS | Construction | 2018 |
| Marker Grønt AS | Agriculture & fishing | 2021 |
| Marker Maskin Og Utleie AS | Administrative & support | 2020 |
| Marveng-Puckett Nuf | Professional & scientific | 2012 |
| Matfatet Ørje AS | Wholesale & retail | 2017 |
| Matfatet Ørje Eiendom AS | Real estate | 2026 |
| Mbat AS | Professional & scientific | 2012 |
| Mbat Eiendom AS | Real estate | 2025 |
| MGH Fysioterapi AS | Health & social care | 2020 |
| Mi-Lo Invest AS | Financial services | 2004 |
| Monolog AS | Arts & recreation | 2018 |
| Mosbæk Eiendom AS | Real estate | 2013 |
| Mosebyneset Eiendom AS | Real estate | 2005 |
| Måsan Handel Ans | Wholesale & retail | 1981 |
| Måstad-Askerud Utmarkslag SA | Real estate | 2025 |
| Nailed by Malena AS | Other services | 2021 |
| Nesset Transport AS | Transport & logistics | 1986 |
| Nestangen Eiendom AS | Real estate | 2019 |
| Nesveien 20 AS | Real estate | 2021 |
| Nilsen Sport & Elektrisk AS | Wholesale & retail | 2005 |
| Noral Norge AS | Wholesale & retail | 2010 |
| Nordicfox AS | Professional & scientific | 2024 |
| Nordisk Tollservice & Spedisjon Ørje AS | Transport & logistics | 2010 |
| Norgesporten Bil AS | Wholesale & retail | 2020 |
| Norgesporten Eiendom Da | Real estate | 2013 |
| Norsk IT Drift AS | Wholesale & retail | 1999 |
| Norsk Trefiberisolering AS | Construction | 2024 |
| Nybo Regenerative AS | | 2026 |
| Næringshagen Østfold AS | Professional & scientific | 2002 |
| Næringsveien 13 AS | Real estate | 2007 |
| O. Mosbæk AS | Wholesale & retail | 2012 |
| Olaf Mosbæk & Co | Wholesale & retail | 1932 |
| Olanto AS | | 2020 |
| Opsal Utmarkslag SA | Real estate | 2024 |
| Orderud AS | Professional & scientific | 2018 |
| Over Kölen AS | Arts & recreation | 2005 |
| Ovnskroken AS | Construction | 2012 |
| Pedersen Anlegg AS | Transport & logistics | 2025 |
| Pernille Martinsen Westlie AS | | 2020 |
| Pote Gjengen AS | Other services | 2019 |
| På Strak Labb AS | Other services | 2025 |
| Pål Martinsen AS | | 2005 |
| R.O.H AS | Real estate | 2019 |
| Rail Norway AS | Construction | 2017 |
| Ramstadveien 8A AS | Real estate | 2020 |
| Reptilutstyr AS | Wholesale & retail | 2020 |
| Richard Adam Martinsen AS | | 2020 |
| Rolighetveien SA | Real estate | 1988 |
| Ruud Blikk Og Ventilasjon AS | Construction | 2023 |
| Røytjernveien Skogsbilveilag SA | Real estate | 2018 |
| S.Ruud Eiendom AS | Real estate | 2023 |
| S.Ruud Holding AS | Construction | 2023 |
| Sandli Bygg AS | Construction | 1998 |
| Sanik AS | Construction | 2022 |
| Serø AS | Real estate | 2019 |
| Skog Og Eiendomservice AS | Agriculture & fishing | 2019 |
| Skogholt 3 AS | Real estate | 2014 |
| Skogholt 4 AS | Real estate | 2018 |
| Skogholt Eiendom AS | Administrative & support | 2000 |
| Skogstad & Eng AS | Real estate | 2010 |
| Slbruk AS | Construction | 2022 |
| Sletta Bygg Og Utleie AS | Real estate | 2021 |
| Sletta Næringspark AS | Real estate | 2012 |
| Slorebyveien SA | Real estate | 1952 |
| Sluseporten AS | Hospitality | 2010 |
| Sluseporten Eiendom AS | Real estate | 2014 |
| Sporty Ørje AS | Arts & recreation | 2010 |
| Steinar Fundingsrud AS | Real estate | 2019 |
| Steinar Nesset AS | Transport & logistics | 2005 |
| Stillesby Eiendom AS | Real estate | 2018 |
| Stillesby Ventilasjon Service AS | Construction | 2009 |
| Strømsfoss Kultur Og Eiendom AS | Arts & recreation | 2020 |
| Studsrud Eiendom AS | Construction | 2005 |
| Syversen Snekkeri AS | Manufacturing | 1997 |
| Søndre Mysens Vei 14 AS | Real estate | 1972 |
| T Syversen Eiendom AS | Real estate | 2021 |
| Tap&Vinn AS | | 2023 |
| Taste of Thai by Charini AS | Hospitality | 2025 |
| Technoweld Ans | Construction | 1994 |
| Thorleif Aas AS | Construction | 1972 |
| Travtjenester AS | Administrative & support | 2020 |
| TT Design AS | Construction | 2015 |
| Tussilago Barnehage AS | Education | 2022 |
| Tvillinggata 1 AS | Real estate | 2026 |
| Tvillinggata 25 AS | Real estate | 2013 |
| TW Capital AS | Administrative & support | 2018 |
| Twist Premium AS | Administrative & support | 2019 |
| Tømrer Kjetil Krog AS | Construction | 2004 |