Are university students less trusting and trustworthy than rural people in Malawi?

Trust and trustworthiness are central to economic development and are frequently studied using behavioral experiments. A concern is that such evidence often relies on student samples, raising questions about external validity. While existing studies, largely from high income countries, suggest that students represent a lower bound on pro-social behavior, little is known about whether it generalizes to low-income country contexts. This paper compares trust, trustworthiness, beliefs, and reciprocity norms between large representative samples of university students and rural adults in Malawi using incentivized trustgame experiments with consistent ingroup–outgroup framing. We show that, contrary to prevailing expectations, students exhibit higher levels of trust and trustworthiness than rural adults. While social distance plays a stronger role among rural adults in form of ingroup–outgroup differences in trustworthiness, such a difference was not found for trust. Surprisingly, we found stronger reciprocity norms and more optimistic beliefs about expected returns among students. Analyzing beliefs and norms as mechanisms, we find that beliefs are associated with trust, while reciprocity norms are strongly related to trustworthiness. Strong norms enhance reciprocity behavior, and especially so in the student sample. Overall, the results demonstrate that assumptions about student samples do not transfer straightforwardly across contexts. In low-income countries, students may not provide a lower bound on pro-social behavior. Social distance, reciprocity norms, and beliefs about the trustworthiness of others can strongly influence cooperation. The findings underscore the value of within-country comparisons for assessing external validity and have implications for the design and interpretation of experimental evidence in development research.