Criticism from dissatisfied citizens is an inevitable part of being an elected politician in a democracy. However, when negative feedback from citizens turns into outright abuse, this can have pernicious personal and democratic consequences. In this study, we therefore investigate how politicians perceive criticisms, insults, threats, and sexist remarks in social media comments. Based on a survey experiment with more than 700 politicians from the local, regional, and national levels, we show that politicians’ assessment of the abusiveness of negative messages are not only affected by the content of the messages but also by political ideology and gender. Left-leaning politicians find negative social media comments to be more abusive than right-leaning politicians do. In addition, politicians are more averse to negative comments targeting women than negative comments targeting men, and male politicians are generally less averse to negative comments than female politicians are. Somewhat surprisingly, politicians are generally not affected by in-party biases, as they exhibit similar levels of aversion towards negative messages directed at co-partisans and out-partisans. While previous research has focused on the extent to which politicians receive online abuse, few studies have examined how politicians perceive potentially abusive messages, and our study thus provides novel insights into what exactly politicians consider to be abusive behavior on social media.