You can pay for your purchases with Avios through the flight search on Iberia.com. Once you have chosen your origin/destination and travel dates, the option Pay with Avioswill appear.
You can also access this option through Purchase flights with Avios. Alternatively, call your Iberia Plus Service Centre.
Another option is to combine Avios and money. Sign in, go the payment page and select the option of paying part of the amount in Avios. You'll see different amounts and their equivalence in euros. Choose whichever suits you best.

If you belong to a loyalty programme of another oneworld alliance airline, you must book through their website or their Call Centre.

Tickets obtained with Avios do not generate Avios.