SIM card for Greece and Turkey

I don't think so. I also seem to remember that mobile phone use by tourists has to be registered in each of these two countries, so it makes sense to by your SIMs as you go and have the supplier activate it for you. They're only about €5 in Greece and most likely a similar amount in Turkey. Of course you pay extra to add the minutes you want. For Greece, the 3 main service providers are Cosmote, Vodafone and Wind. You can buy a Cosmote SIM in any of the Germanos stores spread around the country, including at the Athens Airport in the Secure Departures Hall, or downstairs in the Arrivals Hall at the post office. The SIM available at the post office is either Cosmote or Vodafone, I haven't been able to determine which.

Thank you. This information is very helpful.