This study provides an in-depth examination of the fiscal and governance decentralisation of long-term care (LTC) across OECD countries, offering projections of future fiscal burdens of LTC spending across levels of government. With rapid population ageing and a decrease in the supply of informal care, LTC spending has increased significantly. The paper introduces a novel methodology to estimate LTC expenditures across different government levels, including central and subnational governments. By analysing country cases, it explores the responsibilities assigned to each government level and the implications for service delivery and intergovernmental coordination. The study also discusses the overall anticipated increase of LTC expenditure to 2.3% of GDP by 2040, identifying the most impacted countries. This research contributes to our understanding of LTC systems, highlights the challenges of increasing LTC costs and provides insights for optimising governance and fiscal expenditure.