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Water is a critically important resource for the Mississippi Alluvial Plain (MAP) region, supporting a multibillion-dollar agricultural industry. There are concerns that continued withdrawals of groundwater for irrigation may decrease future water supplies. The US Geological Survey (USGS) has a history of conducting research in the MAP region and recently began an effort to integrate multiple monitoring analyses and modeling to characterize and project water availability for the region. Here, we utilize the data and results from existing national-scale datasets (Hutson and others, 2004; Kenny and others, 2009; Maupin and others, 2014; Homer and others, 2015; and Reitz and others, 2017a, b) and refine them to create long-term steady state annual water budgets at a regional scale (the MAP) from 2000 to 2013. The water budget is described and mapped as the distribution of available water into three components:(1) evapotranspiration (65 percent);(2) quickflow runoff to streams (27 percent); and (3) groundwater recharge (8 percent). We also present a comparison of long-term recharge rates with groundwater extraction rates. These results will be useful as a starting point for the water budget and evaluations of future water availability in the MAP.