+1-844-414-9223 Delta Air Lines offers a comprehensive UM program to ensure the safe and comfortable travel of children flying alone. The Delta unaccompanied minor age is 5 to 14 years for children who are flying alone or without a passenger who is at least 18 years old. The service is optional for kids aged 15 to 17.Delta only permits unaccompanied minors on direct or nonstop flights—no plane changes are permitted.