socNAMs provides a comprehensive and comparative dataset for researchers to identify how students’ recent migration and their school setting relates to their social wellbeing, particularly regarding their feelings of loneliness. At the individual level, socNAMs collected information on: (1) socio-demographic variables of NAMs; (2) migration and family context; (3) social relationships; (4) school experiences; (5) self-perceived wellbeing (physical and social); and (6) experiences with discrimination. The student questionnaire is available in 16 languages. To gain a further understanding of the impact of the school environment on NAMs, socNAMs collected contextual information primarily concerning school social capital by including data collected from teachers and reception-class coordinators.