| APARO ENERGI AS | 993167800 | KONGSVINGER |
| A PAULSEN & SØNNER AS | 939284699 | IBESTAD |
| AP BYGG AS | 923706569 | TRYSIL |
| APRIL ARKITEKTER AS | 910279009 | OSLO |
| APROVA AS | 995156954 | ARENDAL |
| APURGO AS | 994807609 | TRONDHEIM |
| AQILA AS | 937155085 | VESTVÅGØY |
| AQUA FLIS AS | 991912851 | NORDRE FOLLO |
| AQUAPARTNER AS | 963164157 | GRIMSTAD |
| AQUARIUS RØRLEGGERBEDRIFT AS | 992887397 | OSLO |
| AQUARØR AS | 995799715 | OSLO |
| AQUA RØRFORNYING AS | 925568201 | TRONDHEIM |
| AQUA RØRSERVICE AS | 931007017 | TRONDHEIM |
| AQUA TECH AS | 971095245 | OSLO |
| AQUA VVS AS | 994596772 | FREDRIKSTAD |
| AQUA VVS SENTERET AS | 983357601 | LARVIK |
| AQWA AS | 998593956 | SANDEFJORD |
| ARAI PROSJEKT AS | 996351122 | SKIEN |
| AR ANLEGG AS | 930899631 | KRISTIANSAND |
| ARA RØR AS | 930335967 | OSLO |
| ARBO ENTREPRENØR AS | 966177810 | DRAMMEN |
| ARCA GLASS OG FASADE AS | 920554091 | STAVANGER |
| ARCA NOVA ENTREPRENØR AS | 984925360 | FREDRIKSTAD |
| ARC ARKITEKTER AS | 978702481 | TRONDHEIM |
| ARC ARKITEKTUR AS | 914894603 | TIME |
| ARCELORMITTAL CONSTRUCTION NORGE AS | 976289862 | LILLESTRØM |
| ARCHI BYGG AS | 915137083 | OSLO |
| ARCHITECTOPIA AS | 997993381 | OSLO |
| ARCHUS ARKITEKTER AS | 943864306 | OSLO |
| ARC-ID AS | 991366997 | STORD |
| ARCO ENTREPRENØR AS | 960670507 | RAKKESTAD |
| ARCON ENTREPRENØR AS | 924771232 | OSLO |
| ARCON PROSJEKT AS | 963028644 | NAMSOS |
| ARCONSULT OVE BØE AS | 940758629 | ULLENSAKER |
| ARCON TØMRER OG EIENDOMSSERVICE AS | 931268597 | OSLO |
| ARCTIC BYGG AS | 983551564 | NORDKAPP |
| ARCTIC ELEKTRO AS | 814910652 | NORDKAPP |
| ARCTIC ENTREPRENØR AS | 993825743 | PORSANGER |
| ARCTIC INSTALLASJON AS | 990513821 | TROMSØ |
| ARCTIC SURVEY AS | 922790094 | RANA |
| ÅRDAL BLIKKENSLAGERSERVICE AS | 993088056 | ÅRDAL |
| ÅRDAL BYGGSERVICE AS | 880428152 | ÅRDAL |
| ÅRDAL OG SKEIE AS | 996500012 | HÅ |
| AREA BYGG AS | 913801547 | SANDEFJORD |
| AREAL+ AS | 920798462 | RINGEBU |
| AREAL BYGG AS | 985731926 | NITTEDAL |
| AREAL ENTREPRENØR AS | 922592136 | DRAMMEN |
| AREAL & PLAN AS | 992804076 | AURE |
| ARECO PROFILES AS | 981686985 | OSLO |
| ARENDAL BYGG AS | 826118172 | ARENDAL |