This paper provides a general overview of the way local governments use Twitter as a communication tool to engage with their citizens. More concretely, it tries to identify factors associated with both the channel activity and citizen engagement, to understand the relationship between media type and citizen engagement and to analyse whether different content generated different levels of engagement. A sample of the 29 most populated Andalusian local governments is examined. The results show that the majority of Andalusian local governments have an official corporate Twitter account with certain level of activity. There is no, however, a significant relationship between the population of a municipality and its citizen's engagement, and there is a significant negative relationship between audience and engagement and between activity and engagement. The findings of the study also show the particular media and content types generate higher engagement than others. This paper contributes to the literature on social media and has practical implications for local governments.