Why It’s Important
The State Department strongly encourages American citizens planning travel abroad to register their travel with the Department of State. Travel registration makes it possible to contact a traveler if necessary, whether because of a family emergency in the United States or because of a crisis in the place the traveler is visiting. Registration is a free service provided by the State Department, and is easily accomplished online at https://travelregistration.state.gov.
Note that, in accordance with the Privacy Act, the Department of State may not release information about those registered without their express written authorization.
If your family needs to reach you because of an emergency, they can pass a message to you through the Office of Overseas Citizens Services, which can be contacted from within the United States at 1-888-407-4747 (toll free), and from overseas at 202-501-4444. The Office of Overseas Citizens Services will contact the U.S. Embassy or Consulate in the country in which you are traveling in order to pass the message to you.
The State Department also advises leaving a detailed itinerary and copies of your passport biographical-data page with a friend or relative in the United States.