List of country calling codes
This article is a travel topic
There are 9 calling zones:
Note: The United States, Canada, and several Caribbean nations share the international calling code 1, with each US state (or parts of US states), province, territory, or island nation given its own three-digit "area code". The following list includes the area codes for such nations outside the US and Canada, as well as those of US possessions outside of the United States proper.
Before dialling the area code, you usually have to dial an international prefix. This is so that the country code won't be confused with the first few digits of a local or national telephone number.
See the list at International dialling prefix.
Alternatively, if you have a mobile phone, you can dial the '+' key first before the country code regardless of which country you are calling from.