Thermal images at different radio wavelengths probe varying subsurface depths of cold, icy bodies like that of Callisto – the outermost of Jupiter’s four largest moons – and therefore can inform us about its surface composition and history of asteroid impacts. Compared to other similar moons, Callisto is understudied and there exist few thermal images of its stable and relatively unaltered surface. However, Callisto’s relative geologic inactivity makes it a popular calibrator target for observatories such as the Atacama Large Millimeter/submillimeter Array (ALMA), which has captured calibrator data of the satellite across multiple frequency bands, including those for which science data have never been obtained. Many of these data have not been evaluated for science merit and could inform us about whether future science runs in those unexplored frequency bands may be valuable. We identified six calibration observations of Callisto taken between 17 July 2012 and 4 November 2012 with spatial resolutions sufficient to resolve major craters on the surface. We present these six thermal images alongside residuals generated by subtracting a thermophysical model from Callisto’s disk to reveal the thermal signature of different geological terrains observed in the optical. In doing so, we observe a north-south hemispheric asymmetry in the residuals that may result from Callisto’s highly perturbed and asymmetric plasma environment. Altogether, these images represent the first of Callisto at these frequencies and serve as a proof-of-concept for identifying and employing calibration data with science merit from the ALMA Observatory.