Previous literature has suggested that PhD students’ mobility has become a fundamental step during doctoral studies, both for training purposes and for creating transnational research networks. In recent years, there has been a significant increase in migration of highly educated and highly skilled Italians. Most studies concentrate on employment-related characteristics of researchers’ and scientists’ mobility, largely neglecting other topics, such as family background characteristics of those who decide to study and go abroad. Using the Istat Survey on occupational conditions of PhD holders conducted in 2014 and 2018 in Italy, along with modelling using multinomial logistic regression analyses, we aim to investigate the relationship between family background characteristics and mobility during PhD studies according to different types of international stay. Our results show that both parental education and mother’s economic activity are related to the propensity for studying abroad among PhD candidates, whereas father’s social class seems to have a lower impact on this decision. The gap in doctoral mobility among PhD students with respect to socio-economic status seems also to vary according to the different types of stay abroad. Overall, our findings intend to shed light on potential disparities related to studying abroad among PhD students and their links to family background, which may have future repercussions on students’ occupational prospects.