For an unaccompanied minor (UM) to travel by air in 2026, you generally need four primary documents. First is a valid Photo ID for the child (such as a passport for international travel or a state-issued ID/birth certificate for domestic). Second, you must complete the airline's specific Unaccompanied Minor Form, which requires the full name, address, and phone number of the adult dropping them off and the adult picking them up. Third, for international travel, a notarized Letter of Consent signed by both parents/guardians is strictly required to prevent international parental child abduction. Finally, the adult dropping the child off must present a valid government photo ID to obtain a "gate pass" to escort the child to the aircraft. It is also wise to include a "Medical Authorization Form" in case of emergencies. Airlines often charge a mandatory "UM fee" (ranging from $50–$150) that must be paid at check-in. Always confirm the specific requirements with your airline 48 hours before departure, as rules regarding age limits and connecting flights can vary by carrier.