This working paper uses a new method to assess the fiscal sustainability of the Irish health system by considering the effects of population change and income growth on both government revenue and health spending over time. Spending on healthcare is comparatively high in Ireland, accounting for 8.4% of GNI in 2019. Health spending from public sources is projected to account for 24% of government revenues in 2040 (up from 20% in 2019). The fiscal balance is projected to slightly deteriorate in Ireland by 2040. Population change is projected to be a much greater driver of future health spending in Ireland over the next 20 years as compared to the OECD average. By coupling health spending projections with government revenue projections, our approach provides policymakers with a broader set of whole-of-government policies to consider when addressing financing shortfalls.