 | NITREX AS | 991853529 | SALTDAL |
| NITTEDAL RØRLEGGERBEDRIFT AS | 916998767 | LILLESTRØM |
| NIVÅBYGG AS | 919290757 | OSLO |
| NJÆRHEIM RØR AS | 996324958 | SANDNES |
| NJS BYGGSERVICE AS | 916538235 | RINGERIKE |
| NK PRO BYGG AS | 898632032 | KRISTIANSUND |
| NKTR HOLDING AS | 922529116 | MODUM |
| NL ARKITEKTUR AS | 931120174 | RINGERIKE |
| NLI ELEKTROSYSTEMER AS | 989042335 | TØNSBERG |
| NLI ENGINEERING AS | 887994722 | TØNSBERG |
| NM RØR AS | 996798011 | OSLO |
| NMS EIENDOM BERGEN AS | 922179611 | BERGEN |
| NMT NORDMARK MASKIN & TRANSPORT AS | 948469049 | HARSTAD |
| NOA VVS AS | 915448941 | STORD |
| NOBEL RØR INSTALLASJON AS | 992139633 | VÅGAN |
| NOBI BYGG OG BETONG AS | 931491865 | VOSS |
| NO BYGG AS | 814968502 | SKIEN |
| NODDELAND BYGG | 984607245 | FROLAND |
| NODE RÅDGIVENDE INGENIØRER AS | 919853557 | BERGEN |
| NOKAS TEKNIKK SØR AS | 979276141 | TØNSBERG |
| NØKKEL-FERDIG AS | 995702444 | HOLMESTRAND |
| NØKLAND RØRLEGGERSERVICE AS | 915514758 | LYNGDAL |
| NØKLEBY EIENDOMSUTVIKLING AS | 919233400 | FREDRIKSTAD |
| NOLA HUS AS | 998501288 | TRONDHEIM |
| NOMELAND MASKIN AS | 988044946 | VALLE |
| NOPEK ELEKTRO AS | 968958356 | LIER |
| NORACTOR AS | 930846589 | LILLESTRØM |
| NOR AGGREGATES AS | 915058493 | VINDAFJORD |
| NORALF REILSTAD | 970386203 | STAVANGER |
| NORAVIND BYGG AS | 928823695 | ØYGARDEN |
| NORAX TYNSET AS | 984697082 | TYNSET |
| NORBECK ENT AS | 994390902 | OPPDAL |
| NORBECK ENTREPRENØR AS | 933455211 | OPPDAL |
| NORBECK RØR AS | 929648870 | ULLENSAKER |
| NORBYGG AS | 923728902 | SARPSBORG |
| NORBYGG TRONDHEIM AS | 920335772 | TRONDHEIM |
| NORCONSULT NORGE AS | 962392687 | BÆRUM |
| NORDAL BYGGSERVICE AS | 917698953 | TØNSBERG |
| NORDAL MASKIN AS | 990800421 | LOM |
| NORDAN RUBICON AS | 971112298 | KLEPP |
| NORD ARKITEKTUR AS | 986692959 | BÆRUM |
| NORDÅS BETONGFORM AS | 917109524 | EIGERSUND |
| NORDASFALT AS | 950501480 | BODØ |
| NORDAVIND ARKITEKTUR AS | 924489235 | TRONDHEIM |
| NORDBÆK BYGG AS | 820978382 | OSLO |
| NORDBALTIC AS | 995641550 | ÅLESUND |
| NORD-BERG AS | 959618267 | ULSTEIN |
| NORDBØ BYGG AS | 912792730 | STAVANGER |
| NORDBOHUS ASKER OG BÆRUM AS | 979222793 | ASKER |
| NORDBOHUS BYGGSERVICE AS | 838064132 | VERDAL |