As a result of increased mobility and restrictive immigration policies in Europe, a growing number of people live in conditional and deportable positions with only limited social rights and access to welfare services. In this keyword, we discuss how the conception of national citizenship that underpins immigration and welfare regimes affects the position of non-citizens, with a particular focus on legal status as an instrument of hierarchisation and social marginalisation in European societies. Immigration systems create hierarchies and divisions by establishing different legal statuses for non-citizens, with wider implications for their position in society. Legal status has become a significant factor in social exclusion and marginality in European societies, intersecting with race, class, gender, and ethnicity to (re)produce social disadvantages. At the same time, migrants’ struggles are situated along the same historical continuum as other previously excluded and marginalised groups, revealing inherent contradictions related to citizenship in modern nation-states and challenging the boundaries of citizenship from the inside.