Objective: The purpose of this study was to describe how a service-learning methodology can promote blood donation among students by increasing levels of knowledge and improving attitudes while developing professional skills. Method: A quasi-experimental study design was utilised. A questionnaire identified barriers and incentives to blood donation in an experimental group and a control group. Participants (n = 81) were students in nursing and primary teacher training courses at the University of Santiago de Compostela. Non-parametric analyses examined differences between participating and non-participating students within the project. Results: Gender and degree programme differences were found. Students who participated increased their level of knowledge (U = 325.500, p < 0.001) and reduced their barriers to blood donation in three of the evaluated dimensions: personal reasons (U = 520.500, p = 0.004), fears (U = 471.500, p = 0.001) and pretexts (U = 576.500, p = 0.020). Non-participants in the service-learning project reported more barriers and fewer external incentives. Conclusion: Service-learning methodology can be a useful strategy to increase blood donation among students in higher education. It increases knowledge, improves attitudes and reduces barriers to donation. This successful interdisciplinary experience could provide the basis for the implementation of new service-learning approaches.