In a context of global-scale inequalities and increased middle-class transnational mobility, this paper explores how the arrival of Western European and North American migrants in Barcelona drives a process of gentrification that coexists and overlaps with the development of tourism in the city. Research has focused increasingly on the role of visitors and Airbnb in driving gentrification. However, our aim is to add another layer to the complexity of neighbourhood change in tourist cities by considering the role of migrants from advanced economies as gentrifiers in these neighbourhoods. We combined socio-demographic analysis with in-depth interviews and, from this, we found that: (1) lifestyle opportunities, rather than work, explain why transnational migrants are attracted to Barcelona, resulting in privileged consumers of housing that then displace long-term residents; (2) migrants have become spatially concentrated in tourist enclaves and interact predominantly with other transnational mobile populations; (3) the result is that centrally located neighbourhoods are appropriated by foreigners - both visitors and migrants - who are better positioned in the unequal division of labour, causing locals to feel increasingly excluded from the place. We illustrate that tourism and transnational gentrification spatially coexist and, accordingly, we provide an analysis that integrates both processes to understand how neighbourhood change occurs in areas impacted by tourism. By doing so, the paper offers a fresh reading of how gentrification takes place in a Southern European destination and, furthermore, it provides new insights into the conceptualisation of tourism and lifestyle migration as drivers of gentrification.