The paper was written as part of a major research programme on trends in the distribution of social and economic outcomes in the UK and the design and impact of social policies. The paper seeks to map out the potential implications of Brexit for social policies and distributional outcomes in the UK. It explores the consequences of the referendum result itself while also looking ahead to the possible impact of the UK’s exit from the European Union. Future effects are considered under five main headings: the effects on the economy, with knock-on consequences for public services; withdrawal from European employment and human rights legislation; implications for EU citizens in the UK and UK citizens in the EU; implications of an end to free movement for public service delivery; and implications of gaining control over resources and regulations, such as those governing state aid. Given the continuing context of high uncertainty, the paper considers what different Brexit scenarios may mean, with a central focus on a scenario in which the UK leaves the single market.