The passenger must pay any taxes and fees levied on air transportation by government authorities. These taxes and fees, which may represent a significant portion of the final cost, are included in the final price of the ticket. When they have been added to the fare, they are shown separately on the line item "taxes and fees".
Taxes and fees change constantly, sometimes after the date the ticket was purchased. If there is an increase in a tax or fee after the date you bought your ticket, you must pay the difference with respect to the amounts shown at the time of purchase. If the fees or taxes paid at the time of purchase are subsequently eliminated or reduced, you may claim a refund from Iberia of the difference paid.
Regardless of the fare paid, if you do not take any of the flights in the booking you are entitled to a refund of the airport taxes for the route in question.