Dual Citizen? What Passport to Use at the Airport
Updated: 1 day ago
When I became a dual citizen of the US and Italy, I really didn't know when to use each passport at the airport. I admittedly still just fan out the whole card deck of family passports in front of check-in agents and let them help me figure it out, but that is a crutch. Here is a quick reference guide not only for me to refer back to, but for fellow Americans traveling abroad.

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If you are an American with dual citizenship leaving the US on a trip, follow these general guidelines for which passport to use. Here, I use the EU as an example because I have dual citizenship with Italy (EU).
Outbound US to EU:
Checking in for a flight: Either passport
Boarding the plane: EU passport
Arriving in Europe: EU passport
Inbound to US:
Checking in for my return flight: U.S. passport ALWAYS
Exiting Europe: EU passport
Pre-flight passport check: U.S. passport ALWAYS
Note: If you had used your EU passport they'd ask for an ESTA or VISA to enter the US
Entering America: U.S. passport
Final rule of thumb provided to me by the kind folks at the Italian Embassy in Miami - "just use the passport that has the shorter line". If you are entering the EU, use your EU passport and join the European line. If you are entering the US, use your US passport.
Just remember you need to effectively "check in" and out of the US, and again in Europe. For the most part, with facial recognition and all the other jazz that the government uses you really shouldn't run into much trouble. Just keep this handy should you need to refer back on what passport to use at the airport if you are a dual citizen.