| Arendal Spirit L.L.C. Nuf | Stavanger | 2019 |
| Arisonas AS | Egersund | 2004 |
| Arne Gjelten Grus AS | Tolga | 2010 |
| Arne Stang Invest AS | Oslo | 2014 |
| Arne Stefan Gustavsson | Klavestadhaugen | 2002 |
| Arnol Offshore Limited Nuf | Hs2 9Db Isle Of Lewis Sc | 2026 |
| Arro Stein AS | Rykene | 2014 |
| AS Maskinservice | Hunndalen | 1982 |
| AS Norsand | Nordfjordeid | 1975 |
| AS Norsk Labrador- & Granitindustri | Oslo | 1911 |
| AS Vestlandske Granitfelter | Bergen | 1925 |
| AS Østlandske Torv | Våler I Solør | 1956 |
| Ascent Graphite AS | Oslo | 2021 |
| Asfalt Og Betongknusing AS | Kristiansand S | 2008 |
| Asset Integrity AS | Stavanger | 2020 |
| At Pedersen AS | Mjåvatn | 2024 |
| At-Joa Invest AS | Sola | 2017 |
| Atd (NE) Ltd | Sunderland Sr4 0Rs Tyne And Wear | 2018 |
| Atdl AS | Oslo | 2021 |
| Atk Engineering and Services Ltd | Sunderland Sr5 3Eu England | 2022 |
| Atlantic Offshore Alpha AS | Straume | 2008 |
| Atlas Services Group Energy Ltd | Cornwall Tr 7 1Hk | 2008 |
| Atno Consulting AS | Masfjordnes | 2012 |
| Attica Exploration AS | Asker | 2021 |
| Aucu Exploration AS | Lier | 2013 |
| Aurelia Holding NV | Oslo | 2001 |
| Aurora Borealis Mining Co. AS | Tromsø | 2009 |
| Aurum Future Minerals AS | Kjøpsvik | 2024 |
| Australian Magnesium Europe GmbH | 691231 Heidelberg | 2004 |
| Australian Offshore Services | Melbourne | 1995 |
| Autonomous Intervention AS | Tananger | 2025 |
| Avium Subsea AS | Lysaker | 2016 |
| Avylon Ltd. Nuf | Aberdeen Ab15 9Bg | 2018 |
| Axis Well Technology Limited | Ab22 8Fd Aberdeen | 2006 |
| Axtech AS | Molde | 2004 |
| B Milne Engineering Ltd Nuf | Ab51 4Rs Aberdeenshire Sc | 2025 |
| B&G Stein AS | Mandal | 2021 |
| B. Gjein Invest AS | Stokke | 2005 |
| Babyshop Sengemagasinet AS | Bergen | 1986 |
| Bae Subsea Ltd | Ab56 5Jp Buckie Moray | 2022 |
| Baker Hughes Norge AS | Tananger | 1998 |
| Baker Kenneth James | E Sussex Tn33 0Na England | 1995 |
| Balanced Rock Limited | Aberdeenshire Ab39 2Tp | 2019 |
| Baltic Diver Norway | De-180 69 Rostock | 2022 |
| Bam Ritchies (Norway) | Camberlet Surrey Gu15 3Xw | 2011 |
| Bamble Pukkservice AS | Stathelle | 2020 |
| Bamsestein AS | Flå | 2009 |
| Barents Kvarts AS | Vadsø | 2024 |
| Baron Energy Ltd Norway | Rosendal | 2001 |
| Bassoe Rig Partners Ltd | Oslo | 2001 |
| Bcpr Company Limited | Th-10260 Bangkok | 2026 |
| Beerenberg AS | Kokstad | 2012 |
| Beerenberg Holding AS | Kokstad | 2006 |
| Beerenberg Services AS | Kokstad | 1979 |
| Belgravia AS | Røyken | 2017 |
| Bengt Are Wågheim Holding AS | Trondheim | 2018 |
| Bergan Black Quarry AS | Tjodalyng | 2023 |
| Bergdrift AS | Stryn | 1992 |
| Bergneset Pukk & Grus AS | Storsteinnes | 2011 |
| Bergquist Pukk AS | Hemnes | 2014 |
| Bergstøl Pukkverk Og Sandtak AS | Nore | 1998 |
| Bernt Roligheten AS | Sandefjord | 2006 |
| Betker AS | Åheim | 2025 |
| Bilfinger Isp Offshore Norway AS | Stavanger | 1984 |
| Bindal Pukk Og Grus AS | Bindalseidet | 2016 |
| Bio Sparkjøp AS | Ingeberg | 1972 |
| Biorest AS | Ålesund | 2018 |
| Biri Pukk AS | Biri | 2014 |
| Bisn Norway AS | Stavanger | 2016 |
| Bjerkeli Sand AS | Vistdal | 2018 |
| Bjordal Maskin Ans | Bjordal | 1994 |
| Bjorli Anlegg AS | Bjorli | 2010 |
| Björgun Ehf | 110 Reykjavik | 2010 |
| Bjødnatjeneste AS | Hafslo | 2014 |
| Bjørkåsen Pukk AS | Kirkenær | 2013 |
| Bjørndalen Pukkverk AS | Skien | 2003 |
| BK Pukk AS | Notodden | 2022 |
| Bleka Gruber AS | Oslo | 1936 |
| Blue Spark Energy Inc. | Ca-Calgary, Alberta T1Y 7E5 | 2013 |
| Bluemech Subsea Ltd Nuf | Ab43 6Nd Aberdeenshire Sc | 2025 |
| Bluestream Offshore BV | 1786 Ra, Den Helder | 2012 |
| Bluewater Inspection Ltd | Norwich Norfolk Nr1 2As | 2015 |
| Bognes Granitt AS | Storjorda I Tysfjorden | 2014 |
| Boka Topaz Operation AS | Fosnavåg | 1998 |
| Bollsta Dolphin Pte Ltd | 039192 Singapore | 2016 |
| Borge Pukkverk AS | Sellebakk | 1989 |
| Borsheim AS | Kleppe | 2000 |
| Borsheim Gruppen AS | Kleppe | 2023 |
| Boskalis Finance BV | 3356Lk Papendrecht | 2000 |
| Boskalis Offshore AS | Stavanger | 1988 |
| Boskalis Offshore Subsea Contracting BV Nuf | Nl-3350 Aa Papendrecht | 1998 |
| BP Oil Int Ltd | Middlesex Tw16 7Bp England | 1995 |
| BPS Norway | 3520 Farum | 2017 |
| Bragerhaug AS | Fagernes | 2014 |
| Braidstone Ltd | Glasgow G32 9Nu | 2011 |
| Brakahaug Natursteinsmuring Ans | Haugesund | 1999 |
| Brandt Aga Knuseservice AS | Hovland | 2015 |
| Brannlia Pukk AS | Hommelvik | 2021 |
| Brattås Sementvarefabrikk Ans | Rindal | 2003 |
| Bravura AS | Asker | 2013 |