Nature Climate Change, Published online: 20 October 2026; doi:10.1038/s41558-026-02766-yClean hydrogen is a versatile decarbonization option, but given its energy-intensive production, high costs and limited near-term supply, uses with the greatest environmental and economic benefits must be prioritized. Analysis of ten end-use sectors identifies high-value applications and suggests that uniform supply-side subsidies risk misallocating clean hydrogen and public funds, highlighting the need for sector-specific demand-side policies.