Building on the notion of the migration state, this article introduces the concepts of ‘migration rent’ and ‘immigration rentier states’ to describe how states that rely heavily on immigration for their wealth derive unearned income from immigration. Both concepts contribute to better understand of the role of migration in the historical transformation of states and the relationship between state, market and society in rentier monarchies and non-rentier states. Drawing on qualitative and quantitative data, I show that the Gulf monarchies, and Saudi Arabia in particular, progressively governmentalized direct and indirect forms of migration rent through migration control and taxation of migrants, both of which were initially brokered by private actors, notably through the kafala or sponsorship system. In doing so, states institutionalise labour market segmentation and differential exclusion of migrants intersecting class, race, nationality, gender, and age. This produces a ‘skill-based order of things’. Rather than outliers, Saudi Arabia offers a magnifying glass that reveals global dynamics of state-led migration control and class-based differential exclusion. Beyond empirical findings, this article thus demonstrates the potential for theoretical innovation in the social sciences based on non-Western polities calling to test the notions of ‘migration rent’ and ‘immigration rentier states’ across contexts.