Right-wing extremism and authoritarianism have been identified as major, if not the major threats to democracy in recent years. The rise of right-wing extremist and populist parties in many democratic countries throughout the world has renewed the interest in identifying the roots and determinants of these anti-democratic attitudes. Even though factors on many levels of analysis (macro-, meso- and micro-level) have been taken into consideration as possible sources of the development of these kinds of positions, the relationship of interpersonal trust with both right-wing extremism and authoritarianism has yet to be systematically examined. The aim of the current study was to shed light on the connection between these constructs by analyzing data from a German representative study conducted in 2018 (N = 2,416). Multiple linear regression found interpersonal trust to reliably predict all facets of right-wing extremism and authoritarianism included in the study, even when controlling for standard socioeconomic factors (e.g. age, gender, education, income). The lack of interpersonal trust may thus be seen as a major contributing factor to right-wing extremist and authoritarian attitudes. As such, it should be included in future studies about this topic and the nature of the revealed connection should be further examined.