The category “heritage” is quickly gaining importance for the study of religion, not least in East Asia. Since the 1990s, Japanese governments, entrepreneurs, and NGO s have invested heavily in heritage preservation, production, and promotion, and other East Asian countries have followed suit. UNESCO recognition is sought after by various state and private actors, who see it as a useful tool for validating and popularising select historical narratives and for acquiring national and international legitimacy. These developments have led to far-reaching transformations in worship sites and ritual practices. Drawing on recent Japanese examples, and comparing these to cases elsewhere in the region, this article constitutes a first step towards a theory of the heritagisation of religion in East Asia. It argues that the heritagisation of worship sites often entails a process of deprivatisation, turning them into public properties that are simultaneously secular and sacred. The article distinguishes between three patterns, which many worship sites and ritual practices that have been inscribed on UNESCO’s World Heritage or Intangible Cultural Heritage Lists, in Japan and beyond, follow: 1) heritage-making constitutes a type of secularisation, 2) it gives rise to new processes of sacralisation, and 3) this enables mass tourism that can lead to far-reaching transformations. Focusing on the first two patterns, the article shows how heritage-making leads to the reconfiguration of sites and practices as national, public, and secular sacred properties.