Transparency in the media has become a fundamental pillar within all democratic societies, as a mechanism for reinforcing government regulation (Anderson, 2009) and citizen trust in institutions (Vos and Craft, 2016). Journalism, which has traditionally acted as a watchdog and a check on power, is now in the midst of a credibility crisis, compounded by polarization and the rise of disinformation. For this reason, various studies advocate that media outlets, just like institutions and governments, should use transparency mechanisms that allow them to respond directly or indirectly to society regarding the content they publish, as an exercise of responsibility. This research aims to evaluate media transparency in the Spanish-Portuguese landscape by means of an index that includes variables studied in the theoretical framework and that come from legislative, academic, and professional sources. These variables have been used to measure corporate and financial transparency, transparency in content production, openness to public participation, and the self-regulation mechanisms of ten media outlets in Spain and Portugal. This study concluded that, with only 43% adherence to the transparency variables analyzed, promoting accountability is still a work in progress for media outlets, and it must be stepped up at both the academic and professional levels.
