Compound flooding poses a growing threat to densely populated delta regions under a warming climate. However, existing compound flood models are often region-specific, limiting consistent assessment of future flood risk across delta regions worldwide. Here, we develop a globally applicable numerical method that couples the atmosphere, ocean, river, and inundation modules to project coastal-pluvial-fluvial compound flooding in delta regions. The method also accounts for multiple factors that amplify future compound flooding, including changes in tropical cyclone (TC) climatology and basin-scale precipitation, sea-level rise, and land subsidence. We apply the method to four representative deltas: the Mississippi River Delta, the Yangtze River Delta, the Bay of Bengal, and the Pearl River Delta. Projected results under four SSP scenarios show widespread intensification of compound flood hazards associated with 200-year storm-surge events. The population exposed to very-high inundation hazard (>4 m) increases from 1.2 million in the historical period (1975–2014) to 2.6–3.8 million by the late 21st century (2061–2100), with the Bay of Bengal showing the strongest amplification (9.6–15.8-fold). This method provides a transferable basis for projecting and managing future compound flood risk for coastal communities worldwide.