| Keb Bygg AS | Hammerfest | 2026 |
| Kebo Glass AS | Blomsterdalen | 2003 |
| Keep Holding on AS | Knapstad | 2015 |
| Keg Holding AS | Storslett | 2008 |
| Keh Holding AS | Ranheim | 2005 |
| Kehima AS | Brandsfjord | 2019 |
| Keht AS | Svensby | 2022 |
| Keipen Holding AS | Brattvåg | 2006 |
| Keiserås Entreprenør AS | Melhus | 2018 |
| Keiserås Rørservice AS | Trondheim | 2025 |
| Keith Newlands | De-87527 Sonthofen | 2022 |
| Keivan Invest AS | Bjørndalstræ | 2020 |
| Kek AS | Elvarli | 2012 |
| Kel Byggrehabilitering AS | Slattum | 2015 |
| Keller Bygg Og Anlegg AS | Svelvik | 2026 |
| Keller Geoteknikk AS | Oslo | 2019 |
| Keller Grundbau Gesmbh Nuf | At 1110 Wien | 2011 |
| Keller Grundläggning AB | Oslo | 1995 |
| Keller Lufttechnik GmbH + Co. KG | De-73230 Kirchheim Unter Teck | 2026 |
| Kellys Gulvservice AS | Sirevåg | 2024 |
| Kelmo AB | Se-371 50 Karlskrona | 2016 |
| Keloo Bygg AS | Ankenes | 2020 |
| Kelsus Enterprises Ltd, Norge | 1075 Nicosia | 2009 |
| Kelvion B.V. | Nl-7005 Bn Doetinchem | 2014 |
| Kelvion Thermal Solutions Germany GmbH | De-44807 Bochum | 2024 |
| Kem Montasje AS | Malm | 2022 |
| Kem Prosjekt AS | Malm | 2021 |
| Kemaro AS | Porsgrunn | 2026 |
| Kemco Møre AS | Surnadal | 2020 |
| Kemco Service AS | Surnadal | 2026 |
| Kemconsult AS | Oslo | 2020 |
| Kemobygg AS | Oslo | 2022 |
| Ken Idar Edvardsen AS | Alta | 2025 |
| Ken Salamonsen Bygg AS | Vadsø | 2017 |
| Kenab I Eda AB Nuf | Se-670 40 Åmotfors | 2025 |
| Kenaz AS | Fornebu | 2020 |
| Kencha Byggservice AS | Trondheim | 2022 |
| Kennet Axelsen Johansen Service AS | Vinterbro | 2015 |
| Kenneth Eggan AS | Klæbu | 2013 |
| Kenneth Foss AS | Kaupanger | 2013 |
| Kenneth Gjerde Bygg AS | Tysse | 2021 |
| Kenneth Gjerde Holding AS | Tysse | 2021 |
| Kenneth Olsen Holding AS | Staubø | 2009 |
| Kenneth Ravneng Fjellsprengning AS | Skjeberg | 2010 |
| Kenneth Thorsen AS | Sannidal | 2026 |
| Kenneth Westli Graving AS | Borgenhaugen | 2006 |
| Kenneth's Malerservice Nuf | Flateby | 2007 |
| Kennys Byggfirma Werner Kenny | Nevlunghavn | 2001 |
| Kenorp Oü | Ee-86602 Pärnu | 2023 |
| Kenroi AB Nuf | 45743 Fjällbacka | 2023 |
| Kent Erichsen AS | Skjeberg | 2020 |
| Kent Johannessen AS | Grålum | 2003 |
| Kent Johannessen Utleie AS | Grålum | 2017 |
| Kent Kran AS | Sande I Vestfold | 2014 |
| Kent Mjølkeråen Holding AS | Hagavik | 2022 |
| Kent Ommedal AS | Straumsbukta | 2018 |
| Kent Persson | Se-780 67 Sälen | 2020 |
| Kentos Holding AS | Drøbak | 2020 |
| Keo Card Invest Norge AS | Oslo | 2010 |
| Kera Isolering AS | Oslo | 2020 |
| Kerama Bygg AS | Frogner | 2024 |
| Keramo AS | Ski | 2024 |
| Kerlefsen Bygg AS | Søgne | 2021 |
| Kerlefsen Eiendom AS | Søgne | 2026 |
| Kerlefsen Holding AS | Søgne | 2026 |
| Kerlefsen Invest AS | Søgne | 2026 |
| Kerlefsen Malermester AS | Søgne | 1983 |
| Kernbo Kernbohrung GmbH | Lysaker | 2004 |
| Kerno AS | Oslo | 2016 |
| Kero Dale AS | Bergen | 1997 |
| Keroc AS | Oslo | 2013 |
| Keroc Holding AS | Oslo | 2015 |
| Kes-Teknikk AS | Bæverfjord | 2014 |
| Kesco Installasjon AS | Oslo | 2000 |
| Kess VVS AS | Kleppestø | 2021 |
| Kestas Bygg AS | Stavanger | 2024 |
| Ket Bygg AS | Ålesund | 2019 |
| Ketel Espeseth AS | Ålesund | 2014 |
| Ketil Vestad Elektro AS | Sekken | 1989 |
| Ketils Bygg & Boligservice AS | Oslo | 2015 |
| Kevin Andersen Invest AS | Sandefjord | 2025 |
| Kevin Murphy Murer AS | Farsund | 2022 |
| Kevo AS | Kjeller | 2014 |
| Key Baltic Solution AS | Hvam | 2018 |
| Kezo Montasje AS | Fjellhamar | 2022 |
| KF Bygg Og Utleige AS | Drangedal | 2004 |
| KF Byggservice AS | Berg I Østfold | 2013 |
| KF Entreprenør AS | Oslo | 2005 |
| Kfa Holding AS | Hemnes | 2020 |
| Kfdi Bygg AS | Holmestrand | 2025 |
| KFG Holding AS | Nittedal | 2007 |
| KFL Bygg & Eiendom AS | Førde | 2022 |
| KFM AS | Bybrua | 2018 |
| KFS Finland | Fi-01300 Vantaa | 2016 |
| KFV Service AS | Kleppe | 2023 |
| Kfz-Meisterbetrieb Und Freileitungsbau | 39606 Iden Ot Sandauerholtz | 2015 |
| KG Betong AS | Ålesund | 2022 |
| KG Bygg Og Betong AS | Hovet | 2009 |
| KG Byggkonsult AS | Vesterøy | 2013 |
| KG Byggservice AS | Slåstad | 2025 |