Telephone numbers in Turkey former area codes other than the primary one mentioned. The country calling code of Turkey is 90. trunk / inner - city code number : 0 international code : 00 Ankara DMS-300 Istanbul DMS-300 İzmir DMS-300 Ankara, İstanbul and İzmir DMS-300 International Exchanges Accept: L/D + area code + subscriber number + ST L /D = language digit : 0 (direct dialing) L /D = language digit : 2 (operator assistance) There are two international operator centers in Turkey, Ankara and İstanbul. Each one of these centers provides operator telephone services according ITU/T dialing: L/D + code11 + ST (Random)
Telephone numbers in Serbia code +383 started to be allocated on 15 December 2016. Telephone numbers in Serbia Regulation of the telephone numbers in Serbia is under the responsibility of the Regulatory Agency of Electronic Communication and Mail Services (RATEL), independent from the government. The country calling code of Serbia is +381. The country has an open telephone numbering plan, with most numbers consisting of a 2- or 3-digit calling code and a 6-7 digits of customer number. The country calling code of Serbia is +381. Serbia and Montenegro received the code of +381 following the breakup of the Socialist Federal Republic of Yugoslavia