As part of the Coastal Carolinas Focus Area Study of the U.S. Geological Survey National Water Census Program, the Soil and Water Assessment Tool (SWAT) was used to develop models for the Pee Dee River Basin, North Carolina and South Carolina, to simulate future streamflow and irrigation demand based on land use, climate, and water demand projections. SWAT is a basin-scale, process-based watershed model with the capability of simulating water-management scenarios. Model basins were divided into approximately two-square mile subbasins and subsequently divided into smaller, discrete hydrologic response units based on land use, slope, and soil type. The calibration period for the historic model was 2000 to 2014. The best available data on water-use from this time period were used, including public water supply, industrial water use, irrigation needs and golf courses. Six future scenario models simulated streamflow during the period 2055 to 2065 based on incorporation of two alternative land use projections, an ensemble of three global climate models, and water demand forecasts. This USGS data release contains all the input and output files for the simulations described in the associated model documentation report (https://doi.org/10.3133/sir20235036).