WASHINGTON, D.C. The State Department has a warning for travelers: Renew your passport as soon as you are eligible, don't wait. 

That's because there are almost 49 million passports that will expire in the next three years, causing a massive amount of renewal requests through 2018, CNN reported. 

But why is there an expected influx of applications?

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The passport renewal crisis

A U.S. law went into effect nine years ago, requiring U.S. citizens to have passports when traveling to Canada, Mexico, Bermuda and the Caribbean.

Passports are only good for 10 years for adults, 5 years for children under the age of 16.

Officials said that due to the amount of renewals, it could take six weeks or longer to get your document, CNN reported.

Renewing a passport book for adults costs $110 plus fees.  Children's passports are $80 plus fees, according to the State Department.

For more information on getting a passport or renewing an existing one, please click here.

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