US Airlines Told To Ignore 'X' Sex Marker In Passports

The United States Customs and Border Protection (CBP) has fully implemented a new rule that requires airlines to enter either male or female under the sex category when processing passengers. This is in compliance with an executive order issued by President Trump at the beginning of his second term to push back against gender ideology in government programs.

The “X” non-binary sex marker was introduced by the Biden Administration in 2022, but the State Department has since suspended it for new passport applications. While passports under the X marker will remain valid travel documents, there are concerns that this new rule could still impact travelers.

US Airlines Will No Longer Recognize “X” As A Sex

As reported by The Guardian, airlines will now disregard the X marker and put either “M” or “F” for each passenger in the CBP’s Advance Passenger Information System (APIS). The rule was issued by US President Donald Trump earlier this year as part of Executive Order 14168, which is titled “Defending Women from Gender Ideology Extremism and Restoring Biological Truth to the Federal Government.” Under the order, government-issued identification documents — including passports, visas and Global Entry cards — must now “accurately reflect the holder’s sex” and can indicate only male or female.

Since the X option was introduced in April 2022, APIS has allowed characters other than “M” or “F” to be entered without triggering an error or resubmission request. Now, the CBP has advised airlines that passports with sex indicators other than M or F should be entered as male or female, even if it doesn’t match their document, essentially telling them to ignore it. The CBP said,

“After the compliance period, APIS will begin returning a resubmit or “X response” which indicates insufficient information requiring resubmission, when values other than “M” or “F” are submitted in the sex field.”

How This Could Impact Travelers

The new ruling is in effect for flights leaving or entering the United States, so domestic journeys remain unaffected. While the US district court in Massachusetts ruled earlier this year that passports containing X were still valid travel documents, holders have concerns about what they might experience when traveling internationally. Advocacy groups claim it will cause confusion at check-in and immigration, adding to the difficulty non-binary travelers already face at airports.

The Guardian reports that there is also a lack of understanding among US agencies about the application of the new ruling. Andy Izenson, senior legal director at the Chosen Family Law Center, spoke with officials from the CBP, TSA and Department of Homeland Security, but was not given a clear answer on how it will be enforced.

It could ultimately come down to the discretion of individual border agents, but it creates uncertainty for those traveling abroad. The Trump Administration is trying to remove the X option for all government-issued documents, including passports. However, the US district court in Massachusetts issued an injunction in June, which the Trump Administration is seeking Supreme Court intervention to remove.

Which Countries Recognize Third Sex Markers?

Dozens of countries worldwide give their citizens the option to choose a third sex marker on their passports. The International Civil Aviation Organization (ICAO) formally recognizes the X marker as a valid sex designation.

The list of countries that allow third sexes on passports is quite diverse. Australia was one of the first to do so back in 2003, while several European nations have recently implemented the choice.

According to a 2021 study by the Williams Institute at UCLA School of Law, over 1.2 million Americans identify themselves as non-binary, the majority of whom are under 29 years old. There is no official data on how many US passport holders have opted to have X amid uncertainty over how long this option will remain available.