Social innovations developed by academic spinoffs (ASOs) are acquiring an ever-increasing relevance in the literature on academic entrepreneurship. Previous studies have considered the importance of the social and institutional contexts of entrepreneurial ecosystems for the development of these innovations, although a greater depth of analysis is required in this field of study. This research analyzes the influence of the frequency of contact with agents of social and institutional contexts of the entrepreneurial ecosystem on the social innovations of ASOs. From a sample of 173 Spanish ASOs, the results indicate that frequent contact with government and academic support units improves this type of innovation of ASOs. Regarding social context, an increase in the frequency of contact with customers, suppliers, and competitors favors the development of social innovation. However, frequent contact with venture capital firms inhibits the development of this type of innovation.