| Strand Varmepumper AS | Jørpeland | 2015 |
| Stranda Anleggsservice AS | Stranda | 1997 |
| Stranda Holding AS | Sandhornøy | 2020 |
| Stranda Maskin AS | Sandhornøy | 2020 |
| Stranda Rørservice AS | Stranda | 1996 |
| Stranda Ventilasjon AS | Stranda | 2026 |
| Strandafjellet Hyttegrend Vann Og Avløp AS | Oslo | 2005 |
| Strandaren AS | Tau | 2015 |
| Strandbakken/Rød Søndre Va Utbygging SA | Vesterøy | 2022 |
| Strandberg Bygg & Vedlikehold AS | Sandefjord | 2025 |
| Strandberg Og Ingebretsen Malerfirma Da | Vennesla | 1998 |
| Strandbergmyra Fjellgård AS | Tonstad | 2018 |
| Strande Maskin AS | Kalandseidet | 1995 |
| Strandegruppen AS | Husøysund | 2024 |
| Strandens AS | Jessheim | 2015 |
| Strandkås Bygg AS | Trøgstad | 2018 |
| Strandkås Eiendom AS | Trøgstad | 2020 |
| Strandkås Holding AS | Trøgstad | 2017 |
| Strandmann Maskin AS | Sæbø | 2006 |
| Strands Elektriske AS | Ankenes | 2003 |
| Stranna Bygg AS | Akland | 2002 |
| Straumbygg AS | Straumsjøen | 2010 |
| Straume Bygg Og Betong AS | Straume | 2017 |
| Straume Byggteknisk Vedlikehold Ans | Straume | 1994 |
| Straume Elektriske AS | Straume | 2011 |
| Straume Maskin AS | Sletta | 2009 |
| Straume Mesterbygg AS | Straume | 2002 |
| Straume Rør AS | Steinsland | 2018 |
| Straume Våtrom AS | Straume | 2013 |
| Straumegruppen AS | Steinsland | 2022 |
| Straumen Elektro AS | Lunde | 2025 |
| Straumen Maskin & Utleie AS | Straumen | 2014 |
| Straumen Maskin Og Service AS | Straumgjerde | 2020 |
| Straumen Skogsvegforening | Borkenes | 2002 |
| Straumsbukta Utleie & Graving AS | Straumsbukta | 2021 |
| Straumsnes Bygg AS | Dale I Sunnfjord | 2011 |
| Straumsnes Holding AS | Harstad | 2017 |
| Straxbo Boliger AS | Steinkjer | 2026 |
| Straye Gruppen AS | Kråkerøy | 2019 |
| Straye Hybridbygg AS | Kråkerøy | 2023 |
| Straye Industri AS | Kråkerøy | 2023 |
| Straye Montasje AS | Kråkerøy | 2021 |
| Straye Stålbygg AS | Kråkerøy | 2007 |
| Straye Tak AS | Kråkerøy | 2022 |
| Straye Trebygg AS | Kråkerøy | 2019 |
| Strema Maschinenbau GmbH | 92237 Sulzbach-Rosenberg | 2010 |
| Stremco AS | Ålesund | 2008 |
| Strendo Bygg & Betong AS | Ål | 2023 |
| Strengtec AS | Vennesla | 2011 |
| Strihl Scandinavia Nuf | Se439 74 Fjärås | 2023 |
| Stril Holding AS | Ågotnes | 2019 |
| Strinda Bygg AS | Ranheim | 2018 |
| Strinda Entreprenør AS | Trondheim | 2020 |
| Strjona AS | Oslo | 2023 |
| Stroh AS | Vågå | 2020 |
| Stroz AS | Stavanger | 2024 |
| Structor AS | Lindås | 2026 |
| Strukta AS | Oslo | 2012 |
| Strukton Rail Aktiebolag Nuf | 126 30 Hägersten | 2014 |
| Struktura AS | Oslo | 2025 |
| Strukturbygg AS | Torvastad | 2022 |
| Stryn Anleggsmaskin AS | Stryn | 2007 |
| Stryn Bygg Og Eigedom AS | Stryn | 2021 |
| Stryn Eiendom AS | Stryn | 2006 |
| Stryn Eiendom Entreprenør AS | Stryn | 2011 |
| Stryn Elektro AS | Hovdebygda | 2023 |
| Stryn Enøk AS | Hjelledalen | 2016 |
| Stryn Invest AS | Stryn | 2010 |
| Strypet Bygg AS | Tynset | 2018 |
| Stråbø Maskin AS | Rennebu | 2003 |
| Stråndbygg AS | Selbustrand | 2016 |
| Stråndbygg Eiendom AS | Selbustrand | 2016 |
| Stråndbygg Holding AS | Selbustrand | 2016 |
| Ströms Elservice AB Nuf | Se-782 91 Malung | 2025 |
| Strøk & Stil Malerteam AS | Nesbru | 2025 |
| Strøkent AS | Tomasjord | 2018 |
| Strøm & Sånn AS | Grimstad | 2023 |
| Strøm El-Installasjon AS | Hitra | 2012 |
| Strøm Elektro AS | Borgenhaugen | 2015 |
| Strøm Entreprenør AS | Brumunddal | 1989 |
| Strøm Gundersen AS | Mjøndalen | 1991 |
| Strøm Gundersen Vestfold AS | Sem | 2016 |
| Strøm Hansen Nuf | 9400 Nørresundby | 2006 |
| Strøm Montasje Service AS | Oslo | 2014 |
| Strøm Og Preiss Maskin Da | Jøa | 2002 |
| Strøm Service AS | Gol | 2008 |
| Strøm Sivertsen AS | Skien | 1997 |
| Strøm Sivertsen Eiendom AS | Skien | 2016 |
| Strøm Sivertsen Holding AS | Skien | 2016 |
| Strøm-Helberg Holding AS | Hundvåg | 2021 |
| Strømberg Blikk & Skifertak AS | Åmot | 2020 |
| Strømberg Elektro AS | Oslo | 2010 |
| Strømbygg AS | Skien | 2024 |
| Strømme Fjellsprenging AS | Stranda | 1996 |
| Strømmen Bolig Varmepumpe AS | Strømmen | 2016 |
| Strømmen Bygg & Eiendom AS | Florø | 2025 |
| Strømmen Bygg AS | Kløfta | 2014 |
| Strømmen Bygg Jobs AS | Lillestrøm | 2023 |
| Strømmen Bygg Og Montasjeservice AS | Strømmen | 1988 |
| Strømmen Byggepartnere AS | Strømmen | 2024 |