U.S. Customs and Border Protection (CBP) has announced updates to the Advance Passenger Information System (APIS) data validation requirements for commercial air carriers. These updates follow the implementation of Executive Order 14168, “Defending Women from Gender Ideology Extremism and Restoring Biological Truth to the Federal Government,” issued in January 2025. The changes primarily affect how airlines transmit passenger data, including sex designations and U.S. passport number formats, when submitting manifests through APIS.

About APIS

APIS is an electronic data interchange system that requires commercial carriers to submit passenger and crew information to CBP before international departures and arrivals. CBP uses the information, such as name, date of birth, nationality, passport number, and sex, to screen travelers and improve border security while facilitating lawful travel.

Key Changes Overview

Sex Field Validation

Effective Oct. 14, 2025, CBP systems will only accept “M” (Male) or “F” (Female) in the APIS sex field. Previously, CBP’s system accepted other characters, including “X”, without returning an error. Under the new validation protocol, entries other than “M” or “F” will now generate an “X Response” error, requiring the airline to resubmit with a “M” or “F” designation before APIS accepts.

According to CBP’s implementation guidance, air carriers must code the APIS transmission as “M” or “F” even if a traveler’s passport displays an “X” or other non-binary designation. This ensures all passenger data conforms to CBP’s accepted input parameters. The guidance does not require or permit carriers to reject travel documents issued with an “X” designation. But a traveler should instruct the airline on whether to enter “M” or “F” in the APIS sex field.

U.S. Passport Number Format Validation

Since Oct. 6, 2025, CBP has enforced enhanced data validation on U.S. passport numbers transmitted via APIS. Valid passport numbers must follow one of the following formats:

Numeric Format: Nine digits (for example, 4XXXXXXXX or higher).
Alpha-Numeric Format: Nine total characters, with the first character being A, X, Y, or Z, followed by eight digits.

Prefix indicators identify passport type:
A – Regular passport
X – Diplomatic passport
Y – Official passport
Z – Service passport

Impact on Business Travelers and Employers

Employer Considerations

• Review travel policies and ensure corporate booking systems capture passport details accurately.
• Instruct travel management providers to follow CBP guidance when booking travelers with non-binary (“X”) designations.
• Educate employees about ensuring that information matches their passport data, except where carriers must use “M” or “F” per CBP guidance.
• Allow additional time for error resolution if APIS transmission issues arise.

Employee Considerations

• Confirm that airline records match your passport data exactly.
• If your passport displays an “X,” understand the airline will transmit either “M” or “F” in APIS per CBP requirements.
• Ensure your passport and booking details align to avoid travel delays.

Carrier Responsibilities

Airlines remain responsible for ensuring accuracy in all APIS data submitted to CBP, including names, dates of birth, and passport numbers. For travelers whose passports contain an “X” or other non-binary designation, airlines are instructed to transmit “M” or “F” in APIS, per CBP’s system configuration. This transmission rule does not affect a traveler’s eligibility to board or enter the United States; it is strictly a data-format limitation within CBP’s automated systems.

Practical Considerations

1. Follow CBP technical guidance to ensure all APIS submissions meet accepted data formats.
2. Coordinate with travel providers familiar with APIS compliance requirements.
3. Monitor implementation dates and anticipate possible transmission errors during the transition period.
4. Maintain accurate records and ensure all travel data matches official documents.

Takeaways

The APIS data updates are technical validation changes, not new travel eligibility restrictions. Travelers with passports displaying an “X” marker remain eligible to enter the United States, but airlines must transmit only “M” or “F” to comply with CBP’s system configuration. Employers should consider updating travel systems and educating employees to avoid disruptions.