This report continues and updates the work published in 2020 on the budgetary impact of biosimilar medicines on the Spanish National Health System. It presents a retrospective and prospective estimate of the savings generated by the marketing of biosimilar medicines for the various active ingredients in which the original medicines no longer have patent protection (or are expected to do so in the coming years for the prospective analysis), as opposed to the continued exclusive marketing of the original medicines with those active ingredients.