+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.