Student start-ups are a significant part of overall university entrepreneurship. Yet, we know little about the determinants of this type of start-ups and, specifically, the relevance of context effects. Drawing on organizational and regional context literature, we develop and test a model that aims to explain student entrepreneurship in a contextual perspective. Based on unique micro-data and using multi-level techniques, we analyse nascent and new entrepreneurial activities of business and economics students at 41 European universities. Our analysis reveals that individual and contextual determinants influence students’ propensity to start a business. While peoples’ individual characteristics are most important, the organizational and regional contexts also play a role and have a differentiated effect, depending on the source of the venture idea and the stage of its development. Organizational characteristics, like the prevalence of fellow students who have attended entrepreneurship education, influence whether students take action to start a new firm (nascent entrepreneurship) but do not seem to support the actual establishment of a new firm. In contrast, the latter is less dependent on the university context but more strongly influenced by regional characteristics. Overall, our study contributes to our understanding of the emergence of start-ups in the organizational context of universities and has implications for initiatives and programs that aim at encouraging students to become entrepreneurs. The final publication is available at Springer via http://dx.doi.org/10.1007/s11187-016-9700-6.