A passport is an internationally recognized travel document that verifies the identity and nationality of the bearer. Only the U.S. Department of State and U.S. Embassies and Consulates have the authority to grant, issue or verify U.S. passports. For travel overseas and to facilitate reentry into the U.S., a valid U.S. passport is the best documentation available.
A valid passport is required to enter and leave most foreign countries. Some countries may allow you to enter with only a birth certificate, or with a birth certificate and a driver’s license. Note, however, that rules established under the U.S. Intelligence Reform and Terrorism Prevention Act of 2004, require that all persons, including U.S. citizens, traveling by air, must present a valid passport to reenter the United States.
If you are traveling by land or sea, make certain that you can return to the United States with the proof of citizenship that you take with you. U.S. regulations require that you document both your U.S. citizenship and your identity when you reenter the United States. For more information about U.S. passport requirements, see html.
Some countries require that a traveler’s U.S. passport be valid at least six months or longer beyond the dates of the trip. In addition, with the number of international child custody cases on the rise, several countries have instituted passport requirements to help prevent child abductions. (Mexican law, for example, requires a child traveling alone, or with only one parent, or in someone else's custody, to carry written, notarized consent from the absent parent or parents if the child is not in possession of a U.S. passport.) Contact the embassy of the foreign destination for more information. A listing of foreign embassies and consulates in the U.S. is available on the Department of State’s website at .