Expired passports cannot be used to travel from the U.S. to an international destination or to travel to a foreign country for any length of stay longer than an airport connection en route to the U.S. or to a U.S. territory.

For international travel in 2026, the answer is a definitive no—all passengers, including infants and children, must possess a valid, unexpired passport to cross international borders. Airlines and border agents are strictly prohibited from boarding passengers with expired documents, and many countries even require the passport to be valid for six months beyond your departure date. However, there is a high-value exception for domestic travel within the U.S.: children under the age of 18 are not required to show any government-issued ID to fly domestically when traveling with an adult. For international emergencies, the premier solution is to contact your nearest embassy or consulate to apply for an "Emergency Passport," which can often be issued within 24–48 hours to facilitate a high-quality, legal return home if your child's documents have lapsed while you were abroad.