Americans traveling abroad may need to wait more than four months for a new passport — and delays are likely to worsen as the busy summer travel season approaches.

That means international travelers should act soon if they're planning a trip later this year or in 2024, travel experts said.

"The only way you can really deal with this is to get ahead of the problem," said Charles Leocha, chairman of Travelers United, a nonprofit advocacy group.

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Passport delays are due to 'unprecedented' demand

The passport backlog has grown in recent months as Americans unleash pent-up wanderlust and take trips abroad that they couldn't earlier in the pandemic. The U.S. State Department must also restaff positions that were reassigned or eliminated as passport demand cratered in 2020.

Passport demand has been "unprecedented," Secretary of State Antony Blinken told Congress in March.

Weekly applications have been about 30% to 40% above last year, he said. While demand is typically seasonal, with the busy season running from March to late summer, "basically it's full time now," he added.

The department received 500,000 applications during some weeks over the winter — a record for that time of year and exceeding the State Department's official projections.

How long it takes to get a U.S. passport

As of March 24, travelers waited 10 to 13 weeks for processing of a routine passport application, the State Department said. (A traditional passport — a passport book — costs $130 to renew; there's an additional $35 acceptance fee for first-time applicants.) Even an expedited application, which costs an extra $60 plus delivery fees, still takes seven to nine weeks.

For those who apply by mail, the delay will be longer. It might take up to four additional weeks for an office to receive and then mail back a new passport, according to the State Department — meaning the total processing time may be more than four months for a routine application.

Processing times are likely to rise further as the busier travel season approaches, the department said.

Since applicants generally must send in their current passports, they'd be unable to travel abroad for that length of time, too, Leocha said.

The department has been hiring staff to boost processing capacity — to ensure customer service phone lines are manned, for example, Blinken said. It has opened satellite offices and authorized overtime pay, and there's a federal task force to marshal the efforts, he added.

A soon-to-expire passport may not allow for travel

U.S. passports are generally valid for 10 years. They're valid for five years if issued before age 16.

Importantly, Americans may not be allowed to travel if their passport expires within a few months after their trip.

For example, the Schengen Area requires a U.S. passport be valid for at least 90 days beyond a traveler's intended date of departure from the region. The Schengen Area encompasses 27 countries in the European Union.

Many countries in the Asia Pacific and Middle East require at least six months of validity for permission to enter. Other areas, such as Hong Kong and Macau, require one month.

"Even if you don't have a trip on the books yet, but your passport is going to expire sometime in the first half of 2024, I'd absolutely just renew it now," said Sally French, a travel expert at NerdWallet.

You may also need to apply for a separate visa to enter certain nations — a process that requires additional time and planning. The State Department website has information about passport and visa requirements for specific countries.

The State Department encourages Americans to apply for passports "well in advance of any planned international travel to avoid last-minute issues."

Expedited options may be available

Travelers may be able to get a more expedited passport for urgent travel if they have an international trip within 14 days.

These appointments must be in person at a passport agency, which are typically near major cities, and may be hard to get given current demand, French said. You must have proof of immediate international travel, such as airline or cruise tickets.

Travelers may be able to get a passport within three business days only in cases of emergency such as a serious illness, injury or death in one's immediate family.

Those who are worried about not getting their passports in time for an upcoming trip "should go directly to a passport office here in the U.S. and see if they can get it done earlier," Leocha said.

Ultimately, the backlog and delays will ease, he added.

"The problem is, that doesn't help you today," he said. "You've got to plan ahead."