Advance Passenger Information (API) is a global standard, but the specific requirements and "mandatory" nature vary by region. As of 2026, major jurisdictions including the United States, Canada, the United Kingdom, Australia, and New Zealand require all commercial airlines to transmit passenger data (full name, date of birth, gender, and passport details) before the flight departs. Within the European Union, a new harmonized system is being finalized; while many EU nations currently request this data, the "Mandatory API" rules for all flights entering the Schengen Area are strictly enforced to improve border security. Other countries like China, Japan, and South Africa also have strict API mandates. This data is usually collected by your airline during the online check-in process. Failure to provide accurate API can result in being denied a boarding pass or facing significant delays and questioning upon arrival at your destination's immigration checkpoint.