| Kaefer Isoliertechnik Gesellschaft M.B.H. | At-1230 Wien | 2012 |
| Kaem AS | Nord-Lenangen | 2025 |
| Kag Holding AS | Oslo | 2007 |
| Kahlbom & Co AS | Oslo | 2013 |
| Kahn Elektro AS | Fredrikstad | 2011 |
| Kahrs Engineering AS | Rykkinn | 1989 |
| Kahtan Malerservice AS | Alversund | 2021 |
| Kai & Anlegg AS | Tau | 1991 |
| Kai & Entreprenørservice AS | Leknes | 1998 |
| Kai Breen Ans | Holter | 1986 |
| Kai Heimes | Fyresdal | 2008 |
| Kai Kreivi | Se-474 32 Elløs | 1997 |
| Kai Og Anlegg Entreprenør AS | Sortland | 1993 |
| Kai Vater Zimmerei Und Holzbau GmbH & Co. KG | 06896 Reinsdorf | 2007 |
| Kaibakken Elektro AS | Tustna | 2003 |
| Kaikan AS | Tromsø | 2016 |
| Kaiko AS | Øvre Ervik | 2023 |
| Kairo AS | Dale I Sunnfjord | 2023 |
| Kairos Mikolaj Wisniewski | Pl-05-220 Zielonka | 2021 |
| Kaitlin Invest AS | Sande I Vestfold | 2021 |
| Kaitomta AS | Surnadal | 2018 |
| Kaiv Sia | Aizkraukle 5101 | 2015 |
| Kaj Ove Madsen | Dk-7800 Skive | 2026 |
| Kaj Peder Tveit AS | Tørdal | 2008 |
| Kajgård Mur & Kakelugn AB Nuf | Se-795 96 Boda Kyrkby | 2024 |
| Kajola AS | Vesterøy | 2018 |
| Kak Prosjekt AS | Moelv | 2014 |
| Kakao Holding AS | Kopervik | 2023 |
| Kaki Holding AS | Flå | 2022 |
| Kal Bud-Kamil Patok | Pl-84-250 Gniewino | 2015 |
| Kala Bygg AS | Greåker | 2024 |
| Kalaba Tekniske Tjenester AS | Vestby | 2017 |
| Kalager Gård AS | Holmestrand | 2016 |
| Kaland Bygg AS | Sykkylven | 2016 |
| Kaland VVS AS | Hauglandshella | 2020 |
| Kalbakken Blikkenslagerverksted AS | Oslo | 2020 |
| Kald & Varm Installasjon AS | Fetsund | 2016 |
| Kaldefoss Maskin AS | Lindås | 2023 |
| Kaldt Og Varmt AS | Askim | 2016 |
| Kaldvansvik Fjellsprengning AS | Elnesvågen | 1996 |
| Kaldåker Anlegg AS | Setskog | 2018 |
| Kalibreringsmannen AS | Hell | 2012 |
| Kalk- Og Teglværksforeningen Af 1893 | 1358 København K | 2010 |
| Kall Invest AS | Engeløya | 2022 |
| Kalland AS | Haugesund | 2006 |
| Kalland Glass Og Tre AS | Haugesund | 2011 |
| Kalland Technology AB | Se-531 56 Lidköping | 2018 |
| Kalle Og Kjetils Rør AS | Hafrsfjord | 2019 |
| Kalleklev Holding AS | Søreidgrend | 2021 |
| Kallekodt Construction AS | Haugesund | 2025 |
| Kallåk Energi Service AS | Oslo | 2019 |
| Kalmar Bygg AS | Vestskogen | 2023 |
| Kalnbygg AS | Fåvang | 2023 |
| Kalseth Bygg AS | Tomasjord | 2020 |
| Kalstveit Bygg AS | Skjold | 2011 |
| Kalt Eiendom AS | Bryne | 1983 |
| Kaltvedt VVS AS | Andebu | 2017 |
| Kalupe AS | Horten | 2012 |
| Kalvatn Golvservice AS | Ørsta | 2025 |
| Kalve Maskin AS | Bakkasund | 2017 |
| Kalvenes VVS AS | Ulset | 1996 |
| Kalvskinnet AS | Grovfjord | 2007 |
| Kalvøy Bygg Ans | Sykkylven | 1998 |
| Kalvøy Entreprenør AS | Averøy | 2026 |
| Kam Bygg AS | Oppdal | 2019 |
| Kama Rørlegger AS | Skotselv | 2018 |
| Kama Service AS | Hakadal | 2016 |
| Kama Solutions Holding AS | Larvik | 2024 |
| Kama Solutions Larvik AS | Larvik | 2024 |
| KAMA1 AS | Hokksund | 2019 |
| Kambygg Viken AS | Lier | 2021 |
| Kameleon Bygg AS | Haltdalen | 2011 |
| Kamelåså AS | Ålesund | 2015 |
| Kamera Og Sikkerhet AS | Auli | 2021 |
| Kamet-Röbäcks AB Nuf | Se-905 80 Umeå | 2019 |
| Kamet-Röbäcks OY | Fi-85101 Kalajoki | 2003 |
| Kamikaze Invest AS | Oslo | 2021 |
| Kamil Bygg AS | Sandvika | 2020 |
| Kaminski Tomasz Tomkan | 84230 Rumia | 2010 |
| Kamo Eiendom AS | Ålesund | 2009 |
| Kamo Ent. AS | Ålesund | 2017 |
| Kamo Invest AS | Ålesund | 2008 |
| Kampen Installasjon AS | Oslo | 1999 |
| Kampen Og Jensen Bygg- Og Eiendomsutvikling AS | Svelvik | 2014 |
| Kampen Rør Service AS | Oslo | 2025 |
| Kamphausen & Partner GBR Modellbau | 46535 Dinslaken | 2009 |
| Kan Rør AS | Harstad | 2016 |
| Kanadevia Inova AG | 8037 Zürich | 1999 |
| Kanadevia Inova Denmark | Dk-6670 Holsted | 2018 |
| Kanadevia Inova Polska Spolka Z Ograniczona Odpowiedzialnoscia | 44-100 Gliwice | 2019 |
| Kanak AS | Oslo | 2015 |
| Kanalisolatøren Ans | Hvam | 2006 |
| Kanalrens AS | Kristiansand S | 2024 |
| Kanalteknik I Göteborg AB Nuf | Se-41454 Göteborg | 2025 |
| Kandal Bygg AS | Sandane | 2005 |
| Kandal Invest AS | Sandane | 2005 |
| Kanebog Maskin AS | Evenskjer | 1997 |
| Kanjoh Holding AS | Tjøme | 2022 |
| Kanon Loading Equipment B.V. | 3840 Aj Harderwijk | 2001 |
| Kanstad El. Service AS | Meistervik | 2005 |