This paper explores the concept of catholicity in light of postsecularism. In the context of Church of England's failed hegemony and late modernity increasingly heightened and increasingly polarised identity formations, the postsecular moment invites a re-examination of how religious concepts like catholicity might reframe our understanding of the common. I argue that catholicity offers a model of universality that is dynamically composed through difference. This model resists both abstract secular universalisms and reactionary particularisms. Rather than being a relic of ecclesial authority, catholicity in this postsecular register becomes a mode of being-with, incl. secular political movements that seek wholeness without erasure. Drawing on postsecular theorists and theological reflections on catholicity as well as Anglicanism, I trace how this concept travels beyond ecclesial boundaries, surfacing in contemporary articulations of the global commons, environmental interdependence, and pluralistic solidarities. I consider how these performances of 'the whole' challenge the binaries of religious/secular, universal/particular, and individual/collective. Ultimately, I propose that a critically retrieved and creatively extended vision of catholicity—understood as a postsecular logic of interrelation—can help reimagine our shared life in a plural and fragile world.