Bet you didn’t know you can have two U.S. passports—at the same time. Well, you can, but it’s not for everyone.

A passport is your ticket to any country in the world, but sometimes what’s between the covers can cause a roadblock along the way. This rarely publicized tip can be a lifesaver for frequent travelers.

Why would you need a second passport?

There are several reasons people would need to have two U.S. passports, and none of them includes “just for fun.” First, some countries in the Middle East don’t like seeing an entry stamp for Israel and may not permit entry. Similar issues arise between India and Pakistan.

More common, however, is the need for visas to visit certain countries. Often, getting a visa requires sending your passport by mail to an embassy, which means frequent travelers are not able to leave the country while they wait. Business travelers often have tight schedules, and sending away a passport for visa formalities is not an option because it essentially grounds them. Additional delays can be incurred if you need several visas for a single trip and have to mail your passport to various places.

There are also countries that require at least two blank pages in a passport to permit entry (South Africa, for example). Some countries issue visas that take up an entire page; others just like to stamp the heck out of it and need the space to do so. A passport can fill up quickly.

How can I get a second book?

There are forms available online with detailed information on how to apply, but unsurprisingly, the requirements can be tedious and confusing. To expedite the process, it is best to use an agency. Your original passport must be sent to the Department of State when applying, which is why faster is better if you have upcoming travel plans.

The Department of State does not just hand out second passports freely. Applicants must include a letter explaining the specific need for acquiring another passport. This is another area where using an agency can be helpful (especially in my experience as a travel writer). Sure, there are additional fees, but the ease and efficiency can be worth it.

Russell Varecha of one such agency, RushMyPassport.com, says, “The benefit of using a courier service is that we are experts in not only securing passports but also navigating through a challenging process. For a second passport, the process and information needed are very specific.”

Agencies like RushMyPassport.com can also ensure that it is processed properly. Some people have had their original passports canceled by mistake and issued a new one due to confusion at the passport office. Varecha points out that they can help prevent mishaps like that by including appropriate notes in the application.

What are the restrictions on a second passport?

A second passport book is typically only valid for two years. It is not meant to replace your 10-year passport, and it is advisable to travel with only one passport at a time if possible. You should enter and exit countries using the same passport.

Like other passports, a second book can include additional pages, but this should be requested in the initial application.

If you have Global Entry, be sure to enter the second passport number in your profile so that it can work at the border kiosks.

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