Last year, more than 72 million Americans traveled abroad, according to the National Travel and Tourism Office. Yet many international travelers are turned away at the airport because even though they have a valid passport, its expiration date does not extend long enough to meet the rules of the country they plan to visit.

“Every day we have people show up without an appointment because of a family emergency or they’ve discovered there’s not enough validity to be allowed to board a plane, and we do everything we can to accommodate an emergency,” said Brenda Sprague, deputy assistant secretary for Passport Services.

Common misunderstandings persist about who needs a passport (answer: everyone, even infants) and the rules regarding expiration dates, which vary by country. Here are Ms. Sprague’s tips for maintaining a valid passport.

REVIEW PASSPORT REQUIREMENTS FOR YOUR DESTINATION The Department of State’s website (travel.state.gov) not only contains directions on passport applications and renewals, but also lists passport validity requirements by country. Mexico, for example, only mandates that passports be valid upon arrival, whereas Chile requires passports that are valid throughout the trip. New Zealand calls for passports that are valid three months beyond the departure date.

“Once you get to six months or less of validity, that’s the time to think about getting a new passport,” Ms. Sprague said.

BE AWARE OF THE SCHENGEN RULES IN EUROPE The six-month rule of thumb applies to the 26 European countries that are part of the Schengen area. The Schengen Borders Agreement allows visitors to travel freely in the region without showing a passport outside of their first point of arrival.

“The rules say three months of validity from the time of entry. It’s a little complicated because they routinely give you 90 days to stay. So you really need six months’ validity on your passport,” Ms. Sprague said.

The Schengen rules cover European Union countries except Bulgaria, Croatia, Cyprus, Ireland, Romania and the United Kingdom, and include Iceland, Liechtenstein, Norway and Switzerland.

IN EMERGENCIES, SEEK EXPEDITED SERVICE If a passport is expiring within two weeks of a trip, travelers can make an appointment at a passport office, show proof of travel and receive expedited service for a higher fee ($170 versus $110 for normal renewals). In cases such as a relative’s serious illness or death, travelers must show proof of the emergency and seek same-day service at an office.

Ms. Sprague urges parents of active military members stationed overseas and students studying abroad or anyone with aging family members in foreign countries to keep an eye on the expiration date of their passport. “In case of an emergency, that’s one less thing to worry about,” she said.

Adult passports are valid for 10 years. Those issued to children under the age of 16 are valid for five years.

Source: NYTimes Travel