Today social media represent an essential instrument for exercising a broad range of fundamental rights. The phenomenon of social media exclusion, arising when a user is prevented from using specific social media websites or parts of them, therefore has profound fundamental rights implications. Based on the analysis of recent case law from the US and Germany, the article outlines the essential characteristics of social media exclusion. Preventing individuals from accessing social media does not nullify their constitutional rights. However, without social media one could not enjoy her fundamental rights to such an enhanced level as has become standard in recent years. This article argues that curtailing the possibility of accessing social media should be subject to minimal constitutional safeguards, and examines which measures have been put in place by national courts in the US and Germany to this end. Finally, this article reflects on the role played by national courts from a general perspective, contending that judges represent a main catalyst of the process of constitutionalisation of the social media environment. National courts articulate traditional constitutional principles in the context of social media, in this way solving constitutional collisions between the state constitutional dimension and that of private platforms.