If you have already bought your ticket and forgot to enter your Iberia Plus card number, you can add it by accessing your bookings under 'Your Flights > Manage your booking'. When you reach your booking details, select 'Passenger information' and enter your loyalty card number. Alternatively, you can add the number during check-in.

Once you have flown, process it through iberia.com in My Iberia/Avios and Elite Points/Missing Avios.