You’ve got everything ready for The Big International Trip You’ve Been Planning Forever: Bags are packed, itineraries are confirmed and you’ve made sure all your documents are in order, including that all important passport. But before you fly, you might want to check its expiration date — because depending on where you’re going, that passport might not work within six months of expiring.

An example: A friend of mine was a few days away from flying to Anguilla to be a bridesmaid in a wedding, when someone told her that she’d better make sure her passport was still valid. She’d checked — it wasn’t expiring for months, so what was the problem?

The problem is that some foreign countries do exactly what the United States itself does, explains ABC News, and require all visitors to have more than six months of validity remaining on their passports before entering the country on the typical three-month time limit for tourists.

Surprised? You’re not alone.

“In the last few months, we have heard of many U.S. citizens having their travel plans disrupted due to some European countries, particularly those in the Schengen area, strictly enforcing passport validity requirements,” Elizabeth Finan, a spokeswoman for United States Consular Affairs, told ABC. “Additionally, some E.U. countries are requiring passports to have six months’ validity because they assume travelers will stay the full three months allowed for visa-free visitors.”

Before you fly, make sure to check the country’s passport requirements on the State Department’s travel advisory website. Otherwise, you’ll be lucky to find a 24-hour passport processing center — which was the case for my friend, at an expense she’d rather not have paid — or if you’re unlucky… well, you’ll be grounded.

How a Little-Known Passport Rule Could Ruin Your Vacation, Costing Thousands [ABC News]

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