Turkey is just one of many countries where data exchange is still a problem. Taxpayers who have forgotten something in their tax return therefore still have some time to clean up. However, you should not wait too long because the tax authorities of different countries are working together more and more efficiently. In the fall of 2021 at the latest, experts expect that in the case of Turkey, the door is likely to close to avoid a procedure for tax evasion.
In order to avoid such a procedure, the voluntary declaration remains. However, that has its price. The conditions for voluntary disclosure have been tightened significantly since 2015. As in the case of Turkey, it is not enough to report foreign income and offshore assets only for the past year.