CBP Enforces Binary Sex Codes and Enhanced US Passport Validation in APIS
Sex Field Requirements: Effective Oct. 14, 2025, CBP systems will only accept “M” (Male) or “F” (Female) in the sex field of APIS transmissions. Any other characters will result in an “X Response-Insufficient Information” error, requiring airlines to resubmit the passenger data with corrected information.
Yep. When traveling, I want to be as inconspicuous as possible. No X for me, no matter how affirming it would feel.