 | INNLANDET LANDSKAPSUTFORMING AS | 916818122 | LILLEHAMMER |
| INNLANDET TAKSTFORRETNING AS | 929007751 | RINGSAKER |
| INNLANDET TAKTEKKING AS | 931996835 | RINGSAKER |
| INNLANDET TRE & BETONG AS | 999311709 | SØR-ODAL |
| INNLANDSCONSULT AS | 986469028 | HAMAR |
| INNMÅLINGSTJENESTER AS | 979927703 | BERGEN |
| INNOMHUS AS | 985806063 | BERGEN |
| INNORE AS | 819337772 | LILLESTRØM |
| INNOVA BYGG AS | 858529972 | BÆRUM |
| INNTRE KJELDSTAD AS | 986044019 | STEINKJER |
| INNVÆR MUR & BETONG AS | 923084851 | VINDAFJORD |
| INNVEST MONTASJE AS | 932422999 | HAREID |
| INOR AS | 986594124 | TROMSØ |
| INRIGO AS | 921474431 | TRONDHEIM |
| INSENTI AS | 996043851 | OSLO |
| IN SITU AS | 992355212 | MOSS |
| INSTALL AS | 911853914 | LIER |
| INSTALLATØRENE AS | 997781694 | OSLO |
| INSTALLATØREN FREDRIKSTAD AS | 912645177 | FREDRIKSTAD |
| INSTALLATØR PER ØVERLAND AS | 919811714 | PORSGRUNN |
| INSTALLATØR STIG LIND AS | 875971832 | ØKSNES |
| INSTANES AS RÅDGIVENDE INGENIØRER | 934485378 | BERGEN |
| INSTANT VVS AS | 916914067 | LILLESTRØM |
| INSTA RØR&REHAB AS | 930831492 | VESTBY |
| INTEC NORGE ØST AS | 928429032 | OSLO |
| INTERIØRFAGHUSET T. LUND AS | 820500482 | STAVANGER |
| INTERNO BYGG & INTERIØR AS | 922885621 | OSLO |
| INTER RØR AS | 932559331 | SULA |
| INTO ELEKTRO AS | 859028012 | KVINNHERAD |
| INTO RØYR AS | 990977631 | KVINNHERAD |
| INVENT AS | 986464352 | BERGEN |
| IPEC MILJØ AS | 935235618 | BIRKENES |
| IPOA AS | 997039297 | MOSS |
| IPRO BYGGMESTER AS | 928834999 | MOSS |
| IR BETONGARBEID AS | 913194020 | SIRDAL |
| IRBYGG ENTREPRENØR AS | 920405746 | OSLO |
| IRPA AS | 999609384 | HALDEN |
| ISACHSEN ANLEGG AS | 970999507 | DRAMMEN |
| ISAKSEN EIENDOM AS | 984255969 | SØRREISA |
| ISAKSEN NYBYGG OG RESTAURERING | 974987007 | BÅTSFJORD |
| ISBANETEKNIKK AS | 929802667 | HOLMESTRAND |
| ISDALSTØ ANLEGGSERVICE AS | 978654363 | ALVER |
| ISHAVSBYEN ELEKTRO AS | 931596039 | TROMSØ |
| ISOMUR AS | 984571941 | TØNSBERG |
| ISOTAK BYGG AS | 947185039 | BÆRUM |
| Isoteks Miljø AS | 943842353 | GJØVIK |
| ISOVENT AS | 999578837 | KINN |
| ISTAND AS | 932206048 | SUNNFJORD |
| ITECH AS | 959686017 | ASKER |
| ITEK AS | 873194472 | LILLESAND |