| VR Training AS | Education | 2024 |
| VT Utvikling AS | Real estate | 2021 |
| VVS Senteret Skien AS | Construction | 2002 |
| Våmartveit Invest AS | | 2017 |
| Vårs Holding AS | Real estate | 2012 |
| W Fredriksen Holding AS | | 2025 |
| W&A Consulting AS | Information & communication | 2012 |
| W&H Eiendom AS | Real estate | 2024 |
| W1EPS AS | Professional & scientific | 2023 |
| Wa Homestead AS | Manufacturing | 2026 |
| Wak Operations AS | Wholesale & retail | 2018 |
| Wakandi Group AS | Information & communication | 2018 |
| Wakandi Holding AS | Information & communication | 2022 |
| Wallprint Norge AS | Manufacturing | 2023 |
| Walmann Salong AS | Other services | 2006 |
| Waløse Invest AS | Real estate | 2022 |
| Wangene AS | Professional & scientific | 2025 |
| Wangene Holding AS | Real estate | 2016 |
| Washill AS | | 2025 |
| Waskaas Auto AS | Wholesale & retail | 2016 |
| Waskaas Service AS | Other services | 2026 |
| WB Holding AS | | 2024 |
| WBG Induction AS | Information & communication | 2025 |
| Webbased AS | Information & communication | 2013 |
| Webcompaniet AS | Information & communication | 2015 |
| Wen AS | Professional & scientific | 2004 |
| Wenstøp AS | Professional & scientific | 1987 |
| Werp Capital Holding AS | | 2022 |
| West & Berg AS | Professional & scientific | 2016 |
| Westlund Holding AS | Information & communication | 2013 |
| Westwood Studio AS | Information & communication | 2022 |
| Wibax Sales AS | Professional & scientific | 2014 |
| Widar Lindgren Transport AS | Construction | 2005 |
| Wiersdalen Maskin AS | Administrative & support | 2024 |
| William Telemark AS | Construction | 2015 |
| Wimi Invest AS | | 2021 |
| Winston Holding AS | Wholesale & retail | 2013 |
| Wirgenes Vei 5A AS | Real estate | 2026 |
| Wiseinvest AS | | 2024 |
| Wisteria Blomster AS | Agriculture & fishing | 2008 |
| Wisteria Holding AS | Agriculture & fishing | 2017 |
| Wolckmar Bygg AS | Construction | 2022 |
| Wolckmar Holding AS | Construction | 2022 |
| WT Property AS | Real estate | 2018 |
| X Cube AS | Other services | 2022 |
| Xcute AS | Information & communication | 2008 |
| XG Eiendom AS | Real estate | 2000 |
| XL Storkjøkken AS | Wholesale & retail | 2021 |
| XT Eiendom AS | Real estate | 2010 |
| Xtragas AS | Professional & scientific | 2017 |
| Yarnonet AS | Wholesale & retail | 2019 |
| Yggdrasil, Te Og Gode Ting AS | Wholesale & retail | 2016 |
| Yildiz Holding AS | | 2026 |
| You Me We AS | | 2025 |
| Youprint AS | Manufacturing | 2026 |
| Ypsilon Contractors AS | Construction | 2003 |
| Yrkesnorsk AS | Education | 2021 |
| Yt Montasje AS | Construction | 2022 |
| Yva AS | Real estate | 2019 |
| Z Elektro Holding AS | Real estate | 2005 |
| Z Invest & Eiendom AS | Real estate | 2009 |
| Z Nett AS | Information & communication | 2008 |
| Z-Ark AS | Professional & scientific | 2006 |
| Zafran Holding AS | Wholesale & retail | 2022 |
| Zala AS | Transport & logistics | 2020 |
| Zanto AS | Real estate | 2024 |
| Zas AS | Wholesale & retail | 2023 |
| Zida AS | Construction | 2026 |
| Zida Service AS | Manufacturing | 2026 |
| Zoma AS | Wholesale & retail | 2007 |
| Zoologen AS | Wholesale & retail | 2002 |
| Zorba Ans | | 1989 |
| Zuraris E Malerservice AS | Construction | 2000 |
| Zuraris Eiendom AS | Construction | 2005 |
| Zuraris Holding AS | Construction | 2005 |
| Åfoss Invest AS | | 2020 |
| Åfoss Utvikling AS | Real estate | 2020 |
| Åkerholmen Gård AS | Other services | 2026 |
| Åkredalen Invest AS | Financial services | 2005 |
| Århusvegen 33 AS | Real estate | 1997 |
| Årmot Bygg AS | Construction | 2015 |
| Årmot Eiendom AS | Real estate | 1989 |
| Åstein Haugerød AS | Manufacturing | 2012 |
| Øag Holding AS | | 2005 |
| Øberg Verktøy AS | Wholesale & retail | 1990 |
| Ødegården Panorama AS | Real estate | 2012 |
| Øen Transport AS | Transport & logistics | 2020 |
| Øfp Consulting | Financial services | 2010 |
| Øk Holding AS | Construction | 2017 |
| Økonomiservice AS | Professional & scientific | 1984 |
| Øp-Holding AS | Real estate | 2017 |
| Øst Entreprenør Og Eiendom AS | Construction | 2026 |
| Østbye Pedersen AS | Real estate | 1937 |
| Østenå Invest AS | Financial services | 2013 |
| Østerlid AS | | 2009 |
| Østerøyveien 42 AS | Real estate | 2020 |
| Østland Invest AS | | 2025 |
| Østlandet Brukt & Antikk AS | Wholesale & retail | 2016 |
| Østlandske Maskinleie AS | Administrative & support | 2013 |
| Østly AS | Real estate | 2020 |