Greek citizen

Nationality law of Greece is based on the principle of jus sanguinis. Greek citizenship may be acquired by descent or through naturalization. Greek law permits dual citizenship. A Greek national is a citizen of the European Union, and therefore entitled to the same rights as other EU citizens.

A child of a Greek citizen acquires Greek nationality automatically at birth. The same applies to children born in Greece whose parents have lived legally and permanently in Greece for five years. Children born abroad and whose parents have lived legally and permanently in Greece for five years become Greek citizens upon successful completion of elementary education (six years). Greeks born abroad may transmit citizenship to their children from generation to generation indefinitely.

An alien born out of wedlock is automatically Greek if the mother is Greek (see matrilineality). If the father is Greek and paternity can be proven (for example, through a paternity test), the child will become Greek when an application is submitted for the child to become a Greek citizen, providing the child has not yet reached the age of 18. An alien who is over 18 may become Greek by naturalization.

A child over 18 of a Greek father does not require naturalization if they can establish a chain of Greek citizenship through properly recorded birth and marriage certificates.

An ethnic Greek born outside of Greece may acquire Greek citizenship by naturalization if they fail to qualify for simple registration as the child of a Greek citizen. (This provision excludes Greek Cypriots, who may seek Cypriot citizenship instead.) The applicant must prove that at least one parent or grandparent was born a Greek national.

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Wikipedia