KembaraXtra – Travel Terms: adult fare
​ In international scheduled air travel, adult fares apply once a passenger reaches their 12th birthday; child fares apply roughly from 2 to 12, and infant fares apply under 2. The entry notes that student and youth discounts are often offered, but that age rules vary widely within countries and across transport modes, giving UK rail examples for domestic and international rail age bands and youth fares.