The people who come to the EU, or leaving the EU, are obliged to declare the money they carry, in case if the sum is 10 thousand EUR, or more. That obligation applies also to the equivalent of that sum in foreign currency, bonds, shares, government stocks, or cheques.
The people who carry less than the mentioned sum, do not have to declare it, but still can do it in their own interest. In such case, they receive a document that confirms their customs declaration. This allows the holder of this document is to certify that the money they imported crossed the border. That document may be useful for instance when you want to deposit the money in a Polish bank.
Despite the fact that Poland is located in the Schengen Zone, that obligation applies also to crossing border of other EU member states.
Legal basis:
