Increasing international travel flows across the planet have drawn attention to socio-spatial justice concerning the impact of tourism and transnational gentrification in cities. We suggest that the growth of tourists and lifestyle migrants can potentially shrink or even deprive a social right to the city. The early work of philosopher and sociologist Henri Lefebvre, particularly The Right to the City (1968), offer valuable elements to understand the potential alienation of local residents from the city centre in the context of a tourism-led urban economy. Several questions arise in this context that are explored here: What injustices arise through the socio-spatial processes and transformation of social spaces due to rapid tourism growth and overtourism? What contribution does Lefebvre’s theoretical work make to current studies on overtourism overall? We examine these questions through a case study in Seville, Andalusia (Spain). It illustrates how its residents lose the right to everyday life in the historic centre and become alienated from their local spaces. Mechanisms of commodification and gentrification contribute to socio-spatial injustices and also make the city “inauthentic” for visitors and residents. In this sense, the right to live and enjoy the city are lost to both groups.