Drawing from the Theory of Planned Behaviour and a review of empirical research on enablers and barriers for student sustainable behaviour, we explore business students' future-oriented sustainability expectations and intentions to engage in sustainability behaviour at their Higher Education Institutions (HEIs). Using a process of configurational theorising with fuzzy set qualitative comparative analysis (fsQCA) and data from 239 business students in two countries--the USA and Germany--we identify multiple equifinal configurations that are associated with high and low sustainability behavioural intentions. Our findings show that students' active engagement in HEIs' sustainability transformation depends on diverse configurations of student characteristics and contextual factors, and various configurations can lead to either high or low sustainability intentions, varying across country contexts. By leveraging these findings to derive strategies that foster sustainability transformation at HEIs, we offer new theoretical and empirical insights to scholars and practical implications.