Fifty years ago, making an international call was a big event for most individuals. The vast majority of calls made to other countries were made by businesses. Calling overseas typically involved operator assistance and big expenses. All of that has thankfully changed, and it’s a simple matter to make overseas calls today using International Direct Dialling (IDD) codes.
International Direct Dialling codes are the means by which calls are made from one country to another without the need for operator assistance. When you wish to direct dial another country, you start by using the International Direct Dialling (IDD) prefix for the country you are in. Regardless of what country you are calling, you must start by dialling the country IDD prefix for where you are located.
A country’s IDD prefix is like a call-out number you must dial from a hotel or business establishment to get an outside line. In this case, the IDD is needed to “call out” to another country.
In the UK for instance, the IDD code is 00. Many other countries around the world have the same IDD prefix as the UK. Senegal, Germany, Costa Rica and New Zealand all have IDD prefix 00. This means that anytime you wish to call another country from one of these countries, you start by dialling 00. Many countries have the IDD prefixes 00 and 011.
IDD prefixes are different from country code numbers. Country codes designate the country you are calling out to. When dialling an international call, the IDD is usually followed by the country code of the country you are calling. Country codes are similar to area codes, only on an international scale.
Unlike IDD numbers, country codes are unique to each country, although some may have more than one. The country code for the UK is 44, while it is 43 for Austria. Country code numbers are followed by the area code and telephone number of the person you are calling. The complete sequence for an international call is therefore IDD number, country code, area code and number.
A common mistake people make when trying to make overseas calls is to neglect to include the IDD prefix in front of the country code. If you are trying to make a call to another country and you aren’t able to make a connection, check that you are dialling the IDD prefix for the country you are calling from first, and that you have the correct IDD number.