Calling New Caledonia from the United States explained:

• 011 - US exit code; dial first for international calls made from the USA or Canada
• 687 - Country Code for New Caledonia
• Phone Number - 6 digits, initial digit for landlines: 2, 3 or 4
• US to New Caledonia international dialing format: 011 687 ??? ???

How to dial to New Caledonia cellular:

• dialing format for calls to a cell phone: 011 687 X?? ???
• initial digit X can be 5, 7, 8 or 9

Phone Books:

• Annuaire Officiel de Nouvelle-Caledonie - OPT White Book, in French