This piece approaches Social Media Councils (SMCs) as institutional responses to the democratic deficit of social media platforms. Our first goal is to analyze their promises and perils to advance democratic legitimacy as framed in democratic theory, and thus assess their potential to address the ends that inspired their creation. Against the concentration of power of private platforms (van Dijck, Nieborg, and Poell 2019; Cohen 2019) and depending on their format, SMCs represent an opportunity to improve compliance with procedural guarantees, or to include more stakeholders in platform-led decision-making processes. Meanwhile, their perils lie in the possibility that, instead of indeed promoting the idea of democratic legitimacy that founded them, SMCs end up contributing to validating private self- regulatory institutions that might improve internal procedures, but bring little remedy for existing power imbalances. Against this assessment, our second goal is to outline relevant possibilities for governance designs of SMC and discuss them regarding their potential to create a more legitimate governance of
social media platforms. In particular, we will focus on enhancing input legitimacy of such institutional forms, all the while supported by the concept of digital citizenship. Increasing input legitimacy, as we see it, is the necessary first step to increase the legitimacy of platform power overall.