Many airlines have an international travel page on their website that helps passengers check the applicable passport requirements. Choose your nationality, destination country and any connection countries from the drop-down menus to learn about the visa or passport requirements.
Airline staff are required to ask for your passport when you check in for an international flight. Since 2007, passports are required for all international travel to and from the United States. Your current, valid passport will always be checked by airline staff.
In the United States, the Transportation Security Administration will check your identification before allowing you to scan your carry-ons at airport security. If you are a U.S. citizen, federal or state ID is required; for international passengers in the United States, a passport is always required. This adds an extra layer of authentication to the airlines' passport checks.
Airline staff make it their job to stay current on passport requirements for international travel and may check your passport and visa information at the gate; however, it is not an airline's responsibility to make sure your visa is valid or acceptable by the immigration officers in the country you are entering. That responsibility falls on you and you alone.
