The Mississippi River Valley alluvial aquifer (“alluvial aquifer”) is one of the most extensively developed aquifers in the United States. The alluvial aquifer is present at the land surface in parts of southeastern Missouri, northeastern Louisiana, western Mississippi, western Tennessee and Kentucky near the Mississippi River, and throughout eastern Arkansas. Historical (1940–2006) and recent (2019–20) aquifer-test datasets were compiled to model transmissivity and hydraulic conductivity of the alluvial aquifer from recent (2018–19) airborne electromagnetic (AEM) survey data. This data release contains the aquifer-test and geophysical data along with computer codes written in Matlab version R2014a syntax used to process the data as described in the corresponding journal article (Ikard and others, 2022). The computer codes were designed to use the datasets contained in comma-separated values (.csv) and ASCII text (.txt) files to: (1) calculate the longitudinal conductance, transverse resistance, and mean electric resistivity frameworks of the alluvial aquifer to depths of 125 meters within the Mississippi Alluvial Plain (MAP) physiographic province from the electric resistivity framework mapped by frequency-domain airborne electromagnetic (AEM) induction surveying along 16,816 line-kilometers (km) of flight path covering 95,000 square-kilometers (km2) of the MAP, (2) correlate the mean electric resistivity at discrete points within the MAP to a database of 160 spatially distributed historical values of alluvial-aquifer transmissivity, quantified by aquifer tests performed in the MAP between 1940 and 2006, and (3) apply user-defined log-linear electric–hydraulic (e–h) relations, defined from the correlation data produced in (2), to 2,364 line-kilometers of separate high-resolution AEM resistivity data covering the 1,000 km2 Shellmound, Mississippi study area (“Shellmound grid”) to calculate alluvial-aquifer transmissivity and hydraulic conductivity where aquifer test data are sparse. The datasets contained herein were extracted from larger parent datasets that are published in a series of U.S. Geological Survey data releases and Scientific Investigation Reports to support the Hydrogeologic Framework component of the MAP Regional Water Availability Study, and citations and web-links to each parent dataset are provided in the metadata record.