The easiest way to get a TK credit card is to apply for one via Garanti Bank in the Turkish Republic of Northern Cyprus. Anyone with a pasport can do this and you do not need a tax number. All they require is a blocked deposit account for 10% more than the monthly card limit. This is well worth doing since you currently earn 2 miles for every YTL spent on TK air tickets - that equates to more than 4 miles per US $!