The Independent Public Revenue Authority is expected within September to receive data on bank accounts held by Greek citizens in 49 countries.
In exchange, Greek banks will send the data to the tax authorities of partner countries on accounts held by foreigners in Greece.
Greek citizens who have not disclosed their bank savings in countries such as Luxembourg, Belgium, Cyprus, Bermuda or the UK, to the Greek authorities could find themselves paying large fines.
Kathimerini says that in the case of undeclared incomes, the fines could reach up to 120% of the deposit.
Interest earned from large amounts of deposits abroad will also be targeted.
However, the paper adds, those who have money overseas, which are justified by their assets and have been taxed, have nothing to worry about.