This study investigates future changes in flooding across the contiguous United States (CONUS) using outputs from 28 global climate models and four scenarios of the Coupled Model Intercomparison Project Phase 6. The results show that CONUS is projected to experience an overall increase in flooding, particularly under higher emission scenarios. Subregional differences are observed, with the Northeast and Southeast showing higher tendencies towards increasing or decreasing flooding due to changes in flood processes at the seasonal scale. The study highlights the need to incorporate climate change into future infrastructure designs and water resource management. Current infrastructure and water resource management are based on the assumption of stationarity, implying that past statistical properties will persist. However, this assumption is challenged by climate change and landscape management changes. The study uses a regression-based approach, leveraging the dense network of streamgages by the U.S. Geological Survey (USGS), to project changes in flood magnitudes. This approach allows for the analysis of flood peak distributions under different scenarios. The study finds that flood extremes are projected to become more severe, with a larger tendency towards larger peaks. The results show that under higher emission scenarios, flood hazards are projected to increase for more extreme events. The study also examines the role of seasonal climate drivers in driving flood extremes, finding that temperature increases and varying precipitation patterns contribute to changes in flood magnitudes. The study also explores the projected changes in trends in flood extremes, finding that historical trends may not persist in the future. The results indicate that flood magnitudes are projected to increase, with significant changes observed in different subregions of the United States. The study emphasizes the importance of incorporating climate change into future infrastructure designs and water resource management to better adapt to and mitigate against flooding. The findings suggest that future flood projections should consider the nonstationary nature of flood extremes and the impact of climate drivers on flood magnitudes.This study investigates future changes in flooding across the contiguous United States (CONUS) using outputs from 28 global climate models and four scenarios of the Coupled Model Intercomparison Project Phase 6. The results show that CONUS is projected to experience an overall increase in flooding, particularly under higher emission scenarios. Subregional differences are observed, with the Northeast and Southeast showing higher tendencies towards increasing or decreasing flooding due to changes in flood processes at the seasonal scale. The study highlights the need to incorporate climate change into future infrastructure designs and water resource management. Current infrastructure and water resource management are based on the assumption of stationarity, implying that past statistical properties will persist. However, this assumption is challenged by climate change and landscape management changes. The study uses a regression-based approach, leveraging the dense network of streamgages by the U.S. Geological Survey (USGS), to project changes in flood magnitudes. This approach allows for the analysis of flood peak distributions under different scenarios. The study finds that flood extremes are projected to become more severe, with a larger tendency towards larger peaks. The results show that under higher emission scenarios, flood hazards are projected to increase for more extreme events. The study also examines the role of seasonal climate drivers in driving flood extremes, finding that temperature increases and varying precipitation patterns contribute to changes in flood magnitudes. The study also explores the projected changes in trends in flood extremes, finding that historical trends may not persist in the future. The results indicate that flood magnitudes are projected to increase, with significant changes observed in different subregions of the United States. The study emphasizes the importance of incorporating climate change into future infrastructure designs and water resource management to better adapt to and mitigate against flooding. The findings suggest that future flood projections should consider the nonstationary nature of flood extremes and the impact of climate drivers on flood magnitudes.