AbstractThe market for socially conscious products and services has grown exponentially in the last years. Consequently, adding social value is among the great challenges that companies have to face nowadays. In view of this, companies need leaders with a set of specific skills that prepares them to act and compete in this new environment. This is especially true for small and medium‐sized enterprises (SMEs), which are even more dependent on their leaders' competences. The aim of this article is to analyse the influence of leaders' sustainability competences on the social entrepreneurial orientation of SMEs of the tourism sector, as well as the influence of this strategy on the firm's performance. The methodology used to validate the measurement scales is exploratory and confirmatory factor analysis and the structural equation modelling technique is applied to analyse the causal relationships proposed in the model. The results show that sustainability competences positively affect social entrepreneurial orientation; specifically, the social risk‐taking and proactivity competence has a positive influence on the economic and social performance of SMEs, and in particular, on their green innovation performance. These results highlight the key role that leaders' competences have in SMEs' social orientation and thus, the importance of training in competences for sustainable development.