 | IBR INNSTALLASJON OG BYGGSERVICE AS | 981648196 | NORDRE FOLLO |
| I BYGG AS | 996013081 | TØNSBERG |
| ICC NORDEN AS | 821277302 | OSLO |
| ICOPALTAK AS | 984834683 | OSLO |
| IDAR NESE AS | 989082108 | ASKØY |
| IDEAL BETONG AS | 924782692 | KARMØY |
| IDEAL BYGG AS | 930089044 | MALVIK |
| IDÉHUS ÅLESUND AS | 991569405 | ÅLESUND |
| IDEHUS ASKER OG BÆRUM AS | 914922259 | ASKER |
| IDEHUS MOLDE AS | 917532648 | MOLDE |
| IDEHUS ØSTFOLDBYGG AS | 990092966 | INDRE ØSTFOLD |
| IDEHUS ROMERIKE AS | 989384899 | EIDSVOLL |
| IDÉHUS TRONDHEIM AS | 885832202 | TRONDHEIM |
| IDLAND BYGG & BETONG AS | 994340972 | GJESDAL |
| IDLAND VVS AS | 912609170 | SANDNES |
| ID RØR AS | 928806782 | OSLO |
| I.E. CONSULT AS | 929564847 | HORTEN |
| I ELEKTRO AS | 925885711 | TØNSBERG |
| IELEKTRO AS | 980887995 | MOLDE |
| IFORM BYGG AS | 999325025 | TRONDHEIM |
| IGANG TOTALENTREPRENØR AS | 922987106 | KLEPP |
| IGLAND GARASJEN AS | 970953302 | GRIMSTAD |
| IGNIST AS | 927386259 | OSLO |
| IGN VVS AS | 914743834 | OSLO |
| I HELMEN UTEMILJØ AS | 926460110 | GRAN |
| IHUGA AS | 911874571 | OSLO |
| IK BYGG AS | 927159295 | NES |
| IKM OCEAN DESIGN AS | 987818638 | SANDNES |
| IKM SAFE CONTROL AS | 976515501 | TVEDESTRAND |
| IKON ARKITEKT & INGENIØR AS | 992869631 | SMØLA |
| IKON NORGE AS | 912678385 | OSLO |
| IKR INGENIØRKONTOR AS | 991326278 | STAVANGER |
| IKT-ELEKTRO AS | 987218452 | OSLO |
| ILF CONSULTING ENGINEERS NORWAY AS | 812667572 | BAMBLE |
| I LIE & SØNNER AS | 945786728 | SØR-AURDAL |
| IMC DIVING AS | 932624036 | BERGEN |
| IMPERIUM SUMMA AS | 926597922 | FÆRDER |
| IMPLENIA NORGE AS | 980332977 | BÆRUM |
| IMTAS HARSTAD AS | 920900305 | HARSTAD |
| IMTAS PROSJEKT AS | 987309113 | RANA |
| IN BY AS | 858261082 | OSLO |
| INCENDIUM CONSULT AS | 815978102 | DRAMMEN |
| INCUBE AS | 999114954 | OSLO |
| INDERDAL ELEKTRO AS | 912211800 | STEINKJER |
| INDERGÅRD BAD AS | 989582070 | ORKLAND |
| INDIAN BYGG AS | 979923953 | LILLESTRØM |
| INDIGO ARKITEKTER AS | 988579165 | BÆRUM |
| INDIRA AS | 912270440 | NARVIK |
| INDRE AGDER TRANSPORT AS | 886471432 | EVJE OG HORNNES |
| INDRE ØSTFOLD BYGG AS | 921571399 | INDRE ØSTFOLD |