This report explores the challenges and needs of families living in the United Kingdom who have relatives who went missing or died in the course of international migration, and provides a policy-oriented overview of laws, advocacies, initiatives and support services applicable to the issue of missing migrants in the country. It is based on qualitative interviews with stakeholders and families, as well as participant observation and desk research, which were conducted in spring 2020, and is part of a project carried out by IOM’s Global Migration Data Analysis Centre that aims to raise awareness of the challenges and coping mechanisms of people with missing migrant relatives in the United Kingdom, Ethiopia, Spain and Zimbabwe. The research demonstrates that the experiences of families of missing migrants in the United Kingdom are shaped by multiple structural constraints, ranging from the circumstances in their countries of origin, the challenges in the places where their loved ones went missing, to their encounters with institutions within the United Kingdom. However, they are also the result of complex interactions shaped by ethnicity, class and gender. Combined, these factors often hinder well-intentioned efforts by families and institutions to get answers concerning the disappearances. Furthermore, the policy and legal frameworks that deal with incidents of missing persons are not inclusive enough to adequately support the specific needs of families of missing migrants. The report concludes with 10 recommendations aimed at government and other relevant actors to help develop targeted responses to the needs of the families of missing migrants in the specific context of the United Kingdom.