This paper deals with the impact of local institutional conditions on the formation of opportunity feasibility beliefs in social entrepreneurship. Embedded in the recent literature on entrepreneurial cognitions, institutions and social entrepreneurship, this study provides a systematic analysis of 776 social entrepreneurs in the UK to identify combinations of causal institutional conditions that collectively explain how early-stage social entrepreneurs form beliefs of feasibility regarding the venture opportunity under pursuit. We contribute to entrepreneurship literature by providing new theoretical and empirical insight into how different combinations of formally and informally organized local institutional features shape the social entrepreneurs’ opportunity perceptions.