The backbone of the European innovation strategy is knowledge transfer from universities to companies, the programmes supporting the creation of university spin‐offs being one of its pillars. In order to achieve a better understanding of this kind of entrepreneurial activity in Spain, this article analyses the relationship between research activity and the creation of spin‐offs and identifies the factors which can be linked to the level of technology used by these companies. Consulting the websites of Spanish universities and their respective Technology Transfer Offices (TTO) led to the identification of 499 spin‐offs. We analysed two groups of universities, correlating their number and technological nature with the research potential of the parent university, the general economic situation and the assistance received in creating this type of company. We found a positive relation between the creation of university spin‐offs and the average number of projects achieved by the university. In addition, their technological nature is positively related to the number of patents awarded to the university. This article focuses on Spain. However, the aspects addressed are common to other countries and its results may therefore be of interest to universities and policy makers wishing to promote the commercialisation of research outcomes.