2010, 2015 and 2017, the text presents the evolution and the paths of the social media use of the selected parliaments. Results and conclusions: Results show a progression in the informative parliamentary use of social media, but they highlight few advances in the creation of deliberative or participative arenas in social platforms. The paper identifies parliamentary actions oriented to integrate the changing media ecosystem, linked to social media, but the institutional intention is limited to the presence and the impact inside the media framework, more than in the promotion of the social media mediated participation.