In this article, we explore the relationship between social media use and participation in protests in Chile. In October 2019, Chile faced the most massive protests since the country’s return to democracy. Due to its magnitude, the media and analysts refer to this process as the “social outburst”. Although these protests engaged broad sectors of the population, most of the protesters were young people. Using a probabilistic and face-to-face survey applied to young people aged 18-29 years, we find that the only social media platform associated with participation in protests was Facebook. Our analysis also shows the importance of the specific activities that people engage in social media. Taking part in political activities on social media is strongly associated with attending protests but using social media platforms to get information or share common interests with other users is not. Furthermore, we examine whether social media has an indirect impact on participation through interpersonal conversation. The results show that Instagram -one of the most popular social media platforms among young Chileans- spurs interpersonal conversation, which in turn increases the likelihood of participating in protests. Our findings suggest that social media still plays a role in shaping people’s political behavior despite changes in the social media environment and in social media consumption patterns.