PurposeIn a world where sustainability is a major aim at all socioeconomic levels, social entrepreneurship plays an important role in achieving the goals that have been set. The purpose of this study is to broaden the knowledge of social start-ups, social incubators and founding teams, highlighting the value of each one. The aim is to use quantitative analysis to determine the possible link between social incubators and social start-up success and identify the founding team profile of social start-ups from each sector according to a sector-based ranking.Design/methodology/approachBootstrap data envelopment analysis (DEA) was used to calculate the efficiency of social incubators and social start-ups and thus quantify the impact, in terms of increased efficiency, of social incubators on social start-ups. Then, using cross-efficiency methodology, a synthetic index was used to analyse the founding team profile of social start-ups. The study is based on primary data from a survey of Spanish social incubators and social start-ups.FindingsThe study provides strong quantitative evidence of the positive effect of social incubators on the development of social start-ups. The size of this effect exceeds the know-how of start-ups. In terms of efficiency gains, this research quantifies the impact of social incubators on this entrepreneurial ecosystem. This impact exceeds 35%. The study also shows that the strongest social start-ups are in the food and information and communication technology (ICT) sectors. The founding teams in these cases have a strong business background, have a high educational level, receive subsidies and express a desire to retain control of the company.Originality/valueThere is an extensive literature dedicated to the analysis of the behaviour and characteristics of traditional incubators, accelerators and start-ups. However, despite the recent rise of social entrepreneurship, studies of social incubators and social start-ups remain scarce. This study provides two novel findings. (1) It shows the importance of creating a social start-up in a context where it receives support throughout all its development stages, providing quantitative insight into the contribution of social incubators and social start-ups. (2) It reveals the profile of founding teams in the highest-ranked business sectors.