Research data services (RDS) are actions undertaken to provide researchers with support, advising, training, information, a technological infrastructure and a regulatory framework with respect to research data management (RDM) throughout the life cycle of the data. The implementation of RDS is an activity that is becoming increasingly important within the functions carried out by academic and research libraries. The aim of this study is to provide a snapshot of the research data services implemented in academic libraries in public universities in Spain, identifying the number and types of services deployed. We conducted a Website Content Analysis of the libraries of the 48 Spanish public universities to discover which RDS they are implementing and promoting. The results show that, despite a lack of institutional policies regarding research data, libraries are deploying these new services, albeit unevenly in terms of both the number of services and the type of support provided. Services related to development of the data management plan (DMP) and preservation of the data in repositories predominate. This inventory is presented as a first step towards learning the level of RDS implementation in Spanish academic libraries, providing a partial perspective and leading the way to exploring other aspects in greater depth in future studies.