The Department of State is responsible for determining the citizenship status of a person located outside the United States or in connection with the application for a U.S. passport while in the United States. The following information explains about dual nationality and U.S. citizenship, including circumstances where U.S. citizenship may be lost.
Dual nationality is the simultaneous possession of two citizenships.
The concepts discussed in this leaflet apply also to persons who have more than two nationalities. Dual nationality results from the fact that there is no uniform rule of international law relating to the acquisition of nationality. Each country has its own laws on the subject, and its nationality is conferred upon individuals on the basis of its own independent domestic policy. Individuals may have dual nationality not by choice but by automatic operation of these different and sometimes conflicting laws. The laws of the United States, no less than those of other countries, contribute to the situation because they provide for acquisition of U.S. citizenship by birth in the United States and also by birth abroad to an American, regardless of the other nationalities which a person might acquire at birth.