Immigrants tend to be seen as less deserving of welfare benefits than native-born citizens, but little consensus exists to explain this finding or how to build greater public support for more inclusive policies. Recent work suggests that support for redistribution may be tied to citizens' perceptions of the "membership commitment" of immigrants. This study provides the first systematic test of this hypothesis in the comparative setting using an original seven country survey conducted in 2021-2022. The survey explored perceptions of immigrants' membership commitment in the host society in seven liberal democracies and their effect on public support for the extension of social benefits to immigrants. The study provides the first comparative test of the relationship between perceptions of shared membership and support for inclusive redistribution. It shows that immigrants systematically suffer a "membership penalty" within host societies across a wide range of states with different citizenship and welfare regimes, with important consequences for welfare state support.