 | CONRAD BYGG AS | 912282570 | VÅGAN |
| CONSEM ENTREPRENØR AS | 987474742 | RÅDE |
| CONSISU AS | 998317649 | BÆRUM |
| CONSOLVO AS | 944024875 | LIER |
| CONSTA AS | 931556444 | OSLO |
| CONSTANT BYGG AS | 821572282 | KONGSBERG |
| CONSTO ANLEGG NORD AS | 917330069 | BODØ |
| CONSTO ANLEGG ØST AS | 916505000 | LILLESTRØM |
| CONSTO ANLEGG SØR AS | 922203652 | ARENDAL |
| CONSTO ANLEGG VEST AS | 926327542 | BERGEN |
| CONSTO AS | 995754606 | TROMSØ |
| CONSTO BERGEN AS | 987769580 | BERGEN |
| CONSTO DAMBYGG AS | 918481613 | KVINNHERAD |
| CONSTRAVIA AS | 919534370 | OSLO |
| CONSTRUCTION FIXXXER WOJCIECH ZACHARA | 935645506 | ULLENSAKER |
| CONSTRUCTION TEAM NORWAY AS | 915449476 | FREDRIKSTAD |
| CONSTRUCTUM AS | 916263406 | FREDRIKSTAD |
| CONSULT GRUPPEN AS | 925747424 | KRISTIANSAND |
| CONTEXT AS | 987545151 | TINN |
| CONTRACTOR BYGG AS | 911644835 | ALSTAHAUG |
| CONTRE AS | 928997944 | GAUSDAL |
| CONTUR AS | 927612372 | KRISTIANSAND |
| CONTURO AS | 931081705 | TØNSBERG |
| CONVA AS | 931051857 | HORTEN |
| CON-WOOD-STEEL AS | 925407399 | ASKØY |
| COOLTEAM AS | 988373354 | OSLO |
| COPLAN AS | 916139101 | SANDEFJORD |
| CORE TECHNOLOGY AS | 913783670 | STAVANGER |
| CORE TECHNOLOGY OSLO AS | 929237889 | OSLO |
| CORIGO AS | 926909223 | OSLO |
| CORRECT BYGG AS | 913042344 | BÆRUM |
| COSMIC BYGG AS | 939429794 | SANDEFJORD |
| COVEI AS | 927790440 | BERGEN |
| COWI AS | 979364857 | OSLO |
| CRAFT ENTREPRENØR AS | 919827270 | ØYGARDEN |
| CR BYGG AS | 926501976 | TØNSBERG |
| CREATIV BYGG AS | 998450179 | FÆRDER |
| CREDO BOLIG AS | 990832587 | HAMAR |
| CRESCO EIENDOM AS | 987579900 | NORDRE FOLLO |
| CRITICAL INFRASTRUCTURE SERVICES AS | 927454939 | LØRENSKOG |
| CRS ELEKTRO AS | 928180034 | MOSS |
| CRUX ARKITEKTUR AS | 922252556 | OSLO |
| CS BYGGPARTNER AS | 979218249 | TØNSBERG |
| CSP AS | 914539552 | ALTA |
| CS VARME OG ENERGI TEKNIKK AS | 897175622 | BÆRUM |
| CURVE STUDIO AS | 928603180 | FÆRDER |
| CV SERVICE AS | 929637275 | NORDRE FOLLO |
| CW RØR AS | 825346392 | NITTEDAL |
| CZECH PRO TEAM AS | 913259122 | OSLO |
| DABYGG AS | 921360371 | ELVERUM |