This One Thing About Your Passport Could Ruin Your Summer Travel Plans

I recently went to Thailand, but before I left, my mom warned me a million times to check the expiration date on my passport, like any sane mom would do. Since it doesn't expire for another three years, my decade-old passport picture and I were in the clear.

And even if it only had three months left before expiring, I still would have thought I was good to go. Apparently three months isn't good enough, though.

Depending on where you want to go, you can't travel there if your passport expires within a specific amount of time.

The US holds the same policy for incoming travelers from different countries, in fact. To travel to the US from a foreign country, visitors need passports that are at least six months away from expiration. So basically, no matter where you live or where you're going, you should be keeping an eye on your expiration date way before traveling.

For Americans, it's most important not to drop the ball on passport renewal when heading to Europe. Most countries allow tourists to stay for three months without a visa, so they just assume people will stay that whole time. If your passport expires within that time, you'll be deported. No one wants that.

These aren't small countries either -- they're ones we all love to visit, like France, Italy and Germany. You can find the full list here.

The reason people aren't aware of this rule is that airports don't notify travelers. If you're traveling and looking to find more information about the passport policy of the country you're visiting, you can check out sites like Expedia or Orbitz, but don't try to find this info on a specific airline's website.

Unaware travelers end up going all the way to the airport, arriving at the ticket window and getting sent home on the spot because of this little-known rule. I couldn't imagine showing up at the airport after the months of planning for my Thailand trip only to be sent home because of my passport expiration date. That would have sucked. Big time.

But I guess that's better than actually boarding the plane and being denied entry when you get there. It's also better than traveling between two countries and getting stopped at customs because of all the different passport requirements. Awkward.

Don't be one of those people who gets sent home before a well-deserved vacay. Check the rules of the country you plan to visit well before you travel there. It's expensive to rush a new passport, so you'll want time to update it if necessary before packing your bags.