According to the laws regulating the migration process, citizens of the Republic of Lithuania, EU citizens and aliens having a permanent residence permit have to declare the change of their place of residence when they are leaving the Republic of Lithuania for more than 6 months. In addition to this, departing persons have to submit to STI an income tax return of a natural person departing permanently from Lithuania. Depending on the concrete situation it may be necessary to perform other formalities as well: to return a residence permit, to inform the banks or other institutions and etc. Usually it is thought that all these procedures are the same and that performing only one of them can result to all the consequences. As a result, not so rarely departing people do not perform all of these procedures, so later on they have to deal with various problems: contributions of mandatory health insurance or other taxes, penalties, default interest, not giving of visas or residence permits. This situation does not pose a huge surprise, because the different procedures are governed by different laws, it is performed in different institutions, in different terms and authorities not so rarely follow the practice of the implementation of these procedures already developed in that institution. That implies that the part of the departing people postpones the performance of these formalities for later time. So that is the reason why variety of legal complications or misunderstandings arise later.