Population registries are the gateway to public services, benefits, and rights. However, despite clear formal rules and procedures, people eligible for registration may still face administrative burdens in obtaining access. In this article, we study the case of the municipal registration of people who experience homelessness in Belgium and the Netherlands—a group that typically suffers from administrative vulnerability. Using data from 61 interviews with social workers and civil servants, we find that burdens are constructed at the municipal level to disincentivize homeless people's access to registration. However, using the Institutional Analysis and Development Framework, we also identify mechanisms in the governance of population registrations and the decentralization of social policies that create incentives for strategic behavior by municipal policy makers and street‐level bureaucrats. By analyzing the interaction between multiple institutional levels, we contribute to understanding how structural mechanisms influence policymakers’ agency in the construction of administrative burdens.