Japan requires all U.S. citizens provide a valid passport and a return on "onward" ticket for entry into the country. Additionally, the United States requires a passport for all citizens wishing to enter or re-enter the country.
Many countries require three or six months of validity on a passport. If a traveler has an onward destination with such a requirement, Japanese official will deny boarding to anyone who cannot present the proper documentation such as a passport that meets this requirement for their complete itinerary.
Travelers anticipating a visit of fewer than 90 days are exempt from having to present a visa for entry into Japan. Those requiring longer stays or anticipating activities that require a visa such as employment or education must file an application with their closest Japanese embassy or consulate.
U.S. citizens cannot change their "visa free" status while in Japan. They must depart, apply for a visa and re-enter for work, study or other long-term visits.
For more information about the Japanese visa waiver program for tourists, Japan's rules on work visas, special visas or other visa issues, contact the Consular Section of the Embassy of Japan.
