Abstract. There is a vast literature on the effect of inequality on trust, establishing that equality must be a pre-condition for the emergence of trust. However, most empirical research either focuses on case studies or uses measures of income inequality, such as the Gini index. In this article, we argue that a measure of inequality of opportunities is preferable to focusing on inequality of outcomes, as it taps into the psychological foundations of trust. In contexts where people feel effort is not adequately rewarded because individuals get ahead due to their family background or individual advantages based on luck, it is difficult to establish the conditions for trustful exchanges and long-lasting relationships. We use data from the European Social Survey to break down income into three different sources: equitable income, inherited social (dis-)advantage, and individual (dis-)advantage. Our measure of inequality of opportunities at the societal level is built on the aggregation of inherited social (dis-)advantage at the individual level. Multilevel models prove the negative effect of personal (dis-)advantages on trust. Panel data analysis indicates that living in societies in which inequality of opportunities is higher leads to lower levels of social trust.