| IVAR ALMROTH TRANSPORT & GRAVING AS | 941675417 | LØRENSKOG |
| IVAR BRÅTHEN MEKANISKE AS | 979901925 | STANGE |
| IVAR GRÆNDSEN | 985857075 | OPPDAL |
| IVAR HAUGEN | 980070336 | SUNNDAL |
| IVAR HORSGÅRD | 967986534 | MOLDE |
| IVAR IKS | 871035032 | STAVANGER |
| IVAR ØDEGAARD GRAVING OG TRANSPORT | 926087169 | EIDSVOLL |
| IVAR TANUM ENTREPRENØR AS | 987837969 | DRAMMEN |
| IVCON AS | 927083485 | NESSEBY |
| IVERK AS | 928719863 | HAUGESUND |
| IVEST CONSULT AS | 993456721 | KINN |
| IVRE ANLEGGSSERVICE AS | 980404889 | ARENDAL |
| IVRE SPORT OG ANLEGG AS | 980585689 | ARENDAL |
| JA ARKITEKTER AS | 928238385 | LINDESNES |
| JACOBSEN BYGG AS | 927456575 | RISØR |
| JACOBSEN & CO AS | 913035801 | HERØY (MØRE OG ROMSDAL) |
| JACOBSEN ENTREPRENØR AS | 923060146 | TØNSBERG |
| JACOBSEN SNEKKERSERVICE AS | 975858847 | TRONDHEIM |
| JADARHUS BYGG AS | 991478442 | STAVANGER |
| JÆGER BRUDVIK ARKITEKTER AS | 920379664 | OSLO |
| JÆRBYGG AS | 925350281 | TIME |
| JÆRCONSULT AS | 889958022 | TIME |
| JÆREN GRAVESERVICE AS | 916524927 | KLEPP |
| JÆRENTREPRENØR ANLEGG AS | 930022837 | HÅ |
| JÆRENTREPRENØR AS | 995817969 | HÅ |
| JÆRHUS Livar Mauland | 969083981 | TIME |
| JÆRMESTER AS | 979541902 | HÅ |
| JÆRPROSJEKT AS | 931710036 | SANDNES |
| JÆRTAKST AS | 997695798 | TIME |
| JÆR TRE AS | 917118167 | HÅ |
| JAHN BRÅTVEIT | 994285084 | LYNGDAL |
| JAHO MUR OG FASADE AS | 926038788 | KRISTIANSAND |
| JAHR TRANSPORT AS | 976500997 | NANNESTAD |
| JAKOB EIMHJELLEN | 977265312 | GLOPPEN |
| JAKOBSEN RØR AS | 913341686 | LINDESNES |
| JAKSA TØMRER & BAD AS | 927167956 | LILLESTRØM |
| J.A LARSEN RØRLEGGERSERVICE | 921889267 | VESTBY |
| JAMES BARBER ARKITEKT | 924786825 | BERGEN |
| JAMO ENTREPRENØR AS | 920053572 | EIDSVOLL |
| JAMTVEIT ENTREPRENØR AS | 930186309 | NOTODDEN |
| JAN ANDERSEN & SØNN AS BYGG OG TØMRERMESTER | 961499429 | HALDEN |
| JAN ANDERS HANSEN | 881322862 | INDRE ØSTFOLD |
| Jan Bauck Arkitektkontor A/S | 945847085 | OSLO |
| JAN EDVARDSEN AS | 937867956 | SARPSBORG |
| JAN EIVIND ELLEFSEN | 865024312 | TØNSBERG |
| JAN E LARSEN AS | 920974074 | FLEKKEFJORD |
| JAN ERIK BRENNE AS | 913099745 | BÆRUM |
| JAN ERIK HAGELUND AS | 989560913 | RINGSAKER |
| JAN ERIK JOHNSRUD AS | 988037648 | BÆRUM |
| JAN-ERIK OLSEN KJØKKEN OG GLASS AS | 910824368 | PORSGRUNN |