The international calling code for Hanoi is + 84 followed by the phone number.
Time Zone difference: Hanoi time zone is UTC/GMT +7 hours.
Currency: Vietnamese unit of currency is Vietnam dong (VND). Most Automated Teller Machines (ATMs) in Hanoi accept foreign credit cards.
Vietnam uses 220 volts in their normal power outlets. Two-hole sockets and three-hole sockets are popularly used in Ha Noi. The hole may be in round or rectangular shape. Although type G plugs (British) with 3 rectangular pins can be used in Vietnam in some places, it is less common and, in most cases, require an adapter.