Recent studies on digital social networks have analyzed their role as part of collective action and their use during electoral campaigns. Based on a study of the Chilean student movement during the 2013 electoral campaign in that country, the article offers an analysis of how Facebook is used by the three student federations that make up the movement. The results suggest informative and organizational aspects take priority in the use of social networks in that context. This trend is mediated by the peculiarities of the movement - the presence of traditional student organizations - and by and the complexity of the relationship with institutional policy, particularly the defense of autonomy against the risks of cooptation, increased by the passage of former leaders of the movement to the latter. The inclination for these spaces to be used more and more at times of increased social mobilization is confirmed, and the tensions between their use by organized collective action (student federations) and by the individuals participating in that action are shown.