This work focuses on the strategic planning of public relations in well-known digital brands, based in Barcelona. This is the host city of the international technology fair “Mobile World Congress” and, at the same time, is in fifth place in Europe, in terms of the number of existing start-ups. The qualitative methodology, using the case study, was the research strategy used, which favoured triangulation in data collection through in-depth interviews and document analysis. Three brands founded on the digital environment were studied, whose activity is developed in the online environment. The results of the study showed that the public relations planning of the analysed digital brands is carried out in four stages: research, planning, implementation and evaluation. The public relations actions of these brands are integrated into marketing strategies and focus on advertising, content marketing and influence marketing actions, which combine creativity and analysis in order to achieve growth hacking goals. The strategies of these brands seek to achieve communication goals in the short term and the techniques used are guided by a management approach by objectives.