 | CONSTRAVIA AS | 919534370 | OSLO |
| CONSTRUCTION TEAM NORWAY AS | 915449476 | FREDRIKSTAD |
| CONSTRUCTUM AS | 916263406 | FREDRIKSTAD |
| CONSULT1 AS | 916538804 | SANDNES |
| 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 |
| COOLTEAM BERGEN AS | 915619878 | BERGEN |
| COPLAN AS | 916139101 | BERGEN |
| CORE ARKITEKTUR AS | 925075345 | BERGEN |
| 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 |
| 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 |
| DAFFY HOLDING AS | 984829515 | GJØVIK |
| DAFRO AS | 990118124 | SKAUN |
| DAGALI BIL & MASKIN Lars Aasberg | 870966512 | HOL |
| DAGALI VVS AS | 998396506 | HOL |
| DAG ARNE NILSEN AVD. KONGSBERG AS | 895595012 | KONGSBERG |
| DAGESTAD MEKANISKE VERKSTED AS | 970975969 | RINGSAKER |
| DAGFIN SKAAR AS | 982310482 | KRISTIANSAND |
| DAGS MASKIN AS | 950429992 | SYKKYLVEN |
| DAHLE BLIKK AS | 976081684 | TRONDHEIM |
| DAHLE MASKIN AS | 926403591 | STRAND |
| DAHLE MEK. VERKSTED AS | 989461346 | BERGEN |
| DAHLEN OPPMÅLING AS | 930671029 | RINGSAKER |