When calling a phone number in another country, there is usually a prefix you have to dial to indicate that you're placing an international call; this varies by country. After that international dialling prefix, you must dial the international country code for the country you are calling, followed by the local number. This is a list of those country codes.
Note: The United States and its possessions, 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.
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.
Countries you are calling from
Afghanistan, Argentina, Armenia, Azerbaijan, Bahamas, Central African Republic, Chad, Chile, European Union, Mainland China, Ecuador, El Salvador, Egypt, Ethiopia, Georgia, Fiji, India, Israel, Jordan, Kyrgyzstan, Macau, Malaysia, Mali, Mexico, Moldova, Nepal, New Zealand, North Korea, Pakistan, Peru, Philippines, Qatar, Saudi Arabia, South Africa, Turkey, Ukraine, Uruguay, Vietnam
Hong Kong, Indonesia, Singapore, South Korea, Thailand
Bahamas, Barbados, Canada, Dominican Republic, USA, St. Lucia