This article aims to contribute to a better understanding of local processes of policy implementation in areas that are characterised by a high level of politicisation and where decisions are underpinned by conflicting normative and functional imperatives. Based on original research data collected in London and Barcelona, it compares the formal entitlements and effective access of irregular migrants to publicly funded healthcare services provided at the local level. My analysis suggests that where the political context makes it difficult for national governments to openly justify and formalise the inclusion of unlawful residents, they tend to resort to a contradictory rhetoric and ambiguous legal frameworks. In practice, this means that the underlying conflicts have to be mediated by lower levels of government, as well as those institutions and individuals responsible for implementing this set of complex, frequently changing and often inconsistent rules and regulations.