To call a local phone in the same city, all you need to do is dialing the 7-digit phone number. However, if you are calling a local phone, but in another city, then you should dial the area code first. For instance, it is 216 for the Asian side of Istanbul, while being 212 for the European side. That area code changes for each city. A phone number on the Asian side could be like 0216 XXX XX XX. One last reminder: The country code of Turkey is 90.