Czech nationality law

The citizenship law of the Czech Republic is based on the principles of jus sanguinis or "right by blood". In other words, descent from a Czech parent is the primary method of acquiring Czech citizenship (together with naturalisation). Birth on Czech territory without a Czech parent is in itself insufficient for the conferral of Czech citizenship. Every Czech citizen is also a citizen of the European Union. The law came into effect on 1 January 1993, the date of the dissolution of Czechoslovakia, and has been amended in 1993, 1995, 1996, 1999, 2002, 2003 and 2005. Since 1 January 2014, multiple citizenship under Czech law is allowed.

The principle of jus sanguinis is used to determine eligibility for citizenship, as is typical in Europe. In principle, any person born to a Czech citizen is a Czech citizen at birth. Whether the person is born in the Czech Republic or elsewhere is irrelevant. Where only the father is Czech, and the parents are unmarried, proof of paternity is required - by the parents making a concerted declaration before the Registry Office or a court. Children born in the Czech Republic to non-Czech parents do not acquire Czech citizenship unless:

Children aged less than 15 years found on the territory of the Czech Republic (where identity of the parents cannot be established) are deemed to be Czech citizens.

During the communist era (1948–89) hundreds of thousands of Czechoslovakian citizens had emigrated into the West. The regime punished emigration by removing Czechoslovak citizenship, along with property confiscation and in absentia prison sentences. Since the Velvet Revolution in 1989, many emigrants demanded their citizenship be restored. Between 1999 and 2004, a special measure allowed them to regain the citizenship, but a few people took advantage of the wording, which "granted" citizenship rather than "restored" it and so got dual citizenship. A few people from Volhynia and Romania also got citizenship.

If a person was a citizen of the Czech and Slovak Federative Republic as of 31 December 1992, he may declare citizenship of either the Czech Republic or Slovakia (gaining Slovak citizenship) assuming he does not have any other citizenship. The Slovak provision allowing for this grant expired in 1993, however the Czech equivalent remains in the citizenship law.

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