Curious if you need to pay full fare for your baby? According to the American Airlines infant policy, infants under 2 years old can travel on a parent’s lap for free on domestic flights. However, for international travel, lap infants are usually charged 10% of the adult fare, plus any applicable taxes and fees. If you prefer your infant to have their own seat, you’ll need to purchase a child ticket at the regular fare. Learn more about the rules and options before you book!