This article aims to compare Portuguese and Spanish radio broadcasting systems from the mid-1970s to the present, from a political economy approach. It analyses the regulatory framework (communication policies) and the ownership structure. It explains how a highly similar situation has been reached despite having stemmed from a situation defined by different principles, when both political transitions began. To do so, this work also analyses the role of deregulation and its globalising nature. The study focuses on three key periods: the initial period in both transitions, the years following both countries' admission into the European Community and the start of the new century. © The Author(s) 2013.