Healthcare priority-setting institutions have good reason to want to demonstrate that their decisions are morally justified—and those who contribute to and use the health service have good reason to hope for the same. However, finding a moral basis on which to evaluate healthcare priority-setting is difficult. Substantive approaches are vulnerable to reasonable disagreement about the appropriate grounds for allocating resources, while procedural approaches may be indeterminate and insufficient to ensure a just distribution. In this paper, we set out a complementary, coherence-based approach to the evaluation of healthcare priority-setting. Drawing on Rawls, we argue that an institutional priority-setter’s claim to moral justification can be assessed, in part, based on the extent to which its many normative commitments are mutually supportive and free from dissonance; that is, on the ability to establish narrow reflective equilibrium across the normative content of a priority-setter’s policy and practice. While we do not suggest that the establishment of such equilibrium is sufficient for moral justification, we argue that failure to do so might—like the proverbial canary in the coalmine—act as a generalised warning that something is awry. We offer a theoretical argument in support of this view and briefly outline a practical method for systematically examining coherence across priority-setting policy and practice.