| A-ARK AS | 921897782 | OSLO |
| Å ARKITEKTER AS | 932393573 | ÅLESUND |
| AARLAND BYGG & EIENDOMSUTVIKLING AS | 987345640 | AUSTEVOLL |
| AARSLEFF FUNDAMENTERING & BORING AS | 990405700 | NOME |
| AARSRUD BYGG AS | 931151053 | OSLO |
| AARSTAD & SØNNER AS | 950600713 | AURSKOG-HØLAND |
| AART ARCHITECTS NO AS | 879423392 | OSLO |
| AARTUN MASKIN | 987394145 | STAVANGER |
| AARTUN TRANSPORT AS | 916916094 | SAUDA |
| AARVIK BYGGMESTER AS | 937965850 | BJØRNAFJORDEN |
| AARVIK TAKST AS | 922308527 | BJØRNAFJORDEN |
| AAS ANUND | 920495354 | KONGSBERG |
| AASBERG GEODATA | 926891561 | AURSKOG-HØLAND |
| AASEBØ BETONGENTREPRENØR AS | 928148408 | ASKØY |
| AASEBØ MURSERVICE AS | 912218856 | ASKØY |
| AASEBØ SAG AS | 987701455 | ASKØY |
| AASEMYR ANLEGGSSERVICE AS | 930791776 | VOLDA |
| AASEN BYGG | 996219836 | TØNSBERG |
| AASEN BYGGELEDELSE AS | 817373372 | DRAMMEN |
| AASEN MASKIN AS | 956814928 | TINGVOLL |
| AASEN MASKIN OG TRANSPORT AS | 988084557 | AURE |
| AASE PROSJEKT AS | 990238316 | OSLO |
| AASE RØR AS | 912722732 | SANDNES |
| AASHEIM RØRSERVICE AS | 978685528 | OSTERØY |
| AASLAND TEKNIKK AS | 989257420 | PORSGRUNN |
| AASLIE ANLEGG AS | 923106960 | SØR-AURDAL |
| AAS & NORDAL AS | 980383660 | NANNESTAD |
| AAS OG HØILAND AS | 940328527 | LYNGDAL |
| AASS MASKINSERVICE AS | 988504548 | FREDRIKSTAD |
| A-AULIE AS | 911577240 | NES |
| AAVITSLAND BYGG | 825598782 | SANDNES |
| ABACUS AS | 916665814 | STAVANGER |
| A & B ANDREASSEN MASKIN AS | 979334494 | VINDAFJORD |
| AB ARKITEKTER AS | 987328762 | FREDRIKSTAD |
| A B BYGG AS | 920329136 | HAUGESUND |
| A-B BYGG AS | 914074312 | BÆRUM |
| A.B BYGG AS | 932755793 | MALVIK |
| ABC BYGGKONTROLL AS | 998532841 | ENEBAKK |
| ABC ELEKTRO AS | 894973552 | HORTEN |
| ABC ELEKTRO TEAM AS | 984259360 | SARPSBORG |
| ABC ENTREPRENØR AS | 997114159 | BÆRUM |
| ABC HÅNDVERKEREN FRANKIEWICZ AS | 998456053 | LILLESTRØM |
| ABCHUS AS | 914313902 | ÅS |
| ABC RØR AS | 948744805 | OSLO |
| ABC - TAK AS | 994021397 | KRISTIANSAND |
| ABD RØRSERVICE AS | 991482148 | INDRE FOSEN |
| ABEA ENTREPRENØR AS | 923056580 | ØVRE EIKER |
| ABEL-ARKITEKTER ABEL-SCHJELDERUP | 985888507 | NESODDEN |
| ABELSEN TØMRERSERVICE AS | 914765730 | INDRE FOSEN |
| ABICON ELEKTRO AS | 976052560 | DRAMMEN |