 | UANZ BYGG AS | 992627042 | STAVANGER |
| UAVHENGIG KONTROLL OSLO AKERSHUS AS | 999146635 | ÅS |
| UAVHENGIG KONTROLL ULLENSAKER AS | 912086038 | ULLENSAKER |
| UBR AS | 912104028 | RINGSAKER |
| UDAHL MASKIN AS | 914775027 | GJØVIK |
| UDNES & AAS BYGG AS | 919626453 | NES |
| UDNES & HOLTER ENTREPRENØR AS | 924496339 | NES |
| UDNES UTEMILJØ AS | 989037218 | NES |
| UGLANE RØYR OG ANLEGG AS | 925834483 | SOGNDAL |
| UHREN VVS AS | 931372637 | NANNESTAD |
| ULEBERG MASKIN OG TRANSPORT AS | 960752023 | BYKLE |
| ULEBERG OG TRYDAL MASKIN AS | 924447575 | BYKLE |
| ULLENSAKER VENTILASJON AS | 816979072 | ULLENSAKER |
| ULLENSVANG BYGG AS | 945690437 | ULLENSVANG |
| ULLERN BYGG AS | 921336098 | OSLO |
| ULLESTAD OG JANSEN TRANSPORT AS | 857905172 | HJELMELAND |
| ULSAKER & GJEILE BYGG AS | 912838749 | NORDRE LAND |
| ULSTEIN ANLEGG AS | 920446582 | HAREID |
| ULSTEIN. AS | 999326536 | VENNESLA |
| ULSTEIN ENTREPRENØR AS | 999503845 | ULSTEIN |
| ULVERSØY AS | 998895332 | RANDABERG |
| ULVESUND ELEKTRO AS | 981400224 | KINN |
| ULVIK KLIMAENTREPRENØR | 832515922 | BÆRUM |
| ULVIK VVS AS | 992106948 | ULVIK |
| ULVSVÅG MASKIN OG TRANSPORT AS | 988336947 | HAMARØY |
| UMBRA PRODUKTER AS | 941527272 | SANDEFJORD |
| UNDAL AS | 996399109 | HÅ |
| UNDERVERK BYGG AS | 918198946 | OSLO |
| UNDHEIM MASKIN AS | 896079212 | EIGERSUND |
| UNIGRAV AS | 818597002 | ØVRE EIKER |
| UNIHEIS AS | 936980058 | OSLO |
| UNIHOUSE SPOLKA AKCYJNA | 923351426 | |
| UNIK FILTERSYSTEM AS | 943578990 | BJØRNAFJORDEN |
| UNIK VVS AS | 977051932 | BERGEN |
| UNIMASKIN AS | 912162788 | RANA |
| UNION BYGG AS | 915048056 | OSLO |
| UNION EIENDOMSUTVIKLING AS | 935711320 | DRAMMEN |
| UNION VVS AS | 930755869 | TRONDHEIM |
| UNIQON AS | 925704172 | STORD |
| UNI RØRSERVICE AS | 925810452 | OSLO |
| UNISPORT SALTEX AS | 928176703 | INDRE ØSTFOLD |
| UNI TAK AS | 912235319 | PORSGRUNN |
| UNITEK AS | 925470449 | TRONDHEIM |
| UNNESTAD BYGG AS | 921027702 | SKIPTVET |
| UNO BYGG AS | 980620328 | KRISTIANSAND |
| UNO DESIGN & ARKITEKTUR AS | 920499902 | BODØ |
| UNU ÅLESUND AS | 931707744 | ÅLESUND |
| UNU AS | 944830642 | KINN |
| URBA AS | 912180921 | OSLO |
| URBAN BYGGKONSULT AS | 825048642 | OSLO |