We often call abroad and dial telephone country codes, but where did they come from and what's the logic behind them?
It all goes back to the creation of ITU (International Telecommunications Union) back in the 1950-s through a merge of two technical committees. The organization worked on standardizing dial codes to make it easier to make international calls. First, they have assigned dial codes to European countries and territories in the 1960-s in what they called the Red Book. Later they developed the Blue book, where ITU assigned the world zone dial codes. European territories, which were not located in Europe got new dial codes assigned in the Blue book.
- Zone 1 – North and Central America, which back then used +1
- Zone 2 – Africa
- Zone 3 and 4 – Europe
- Zone 5 - South America
- Zone 6 - Australia and Oceania
- Zone 7- the USSR
- Zone 8 - Eastern Asia
- Zone 9 - Western Asia and the Middle East
The most popular countries with the biggest population that participated in establishing the standardized dial codes also received the shortest codes, like the USA and Canada. Another country that received a one-digit country code was the USSR - the country was assigned +7, which is now used by Russia and Kazakhstan. All other former Soviet Republics have adopted three-digit codes, which begin with +3 or +9.
It is interesting that among them there are countries that are partially in Europe (like Georgia) but did not receive a European phone country code, while Armenia, which is located entirely in Asia, received a European phone country code. China was not a part of international organizations then and missed out on an opportunity to receive a one-digit phone country code. Central America switched to South American phone country codes.
Why is there no country code +37 now?
+37 used to be a dial code for East Germany, but after the German reunification, the dialing code for the whole Germany became +49.
The current standard
In 1997 ITU has established an E.164 recommendation as a standard for each country for creating international phone numbers. It contains all the information needed to route a call.
- A full telephone number can have a maximum 15 digits
- The first part of the telephone number should be the country code - one to three digits
- The second part is the NDC (National Destination Code)
- The last part is the SN (Subscriber Number)
- Together NDC and SN are the national (significant) number