The Versatile Test Reactor (VTR) that is being designed today is heavily reliant upon the Argonne Reactor Codes (ARC) modeling software for predicting the operational performance of the VTR. Given its usage in the VTR, a set of validation cases appropriate for the VTR must be assembled. The measurements taken in ZPPR-15, Experimental Breeder Reactor II (EBR-II), and Fast Flux Test Facility were chosen and analyzed with the ARC software as part of creating the necessary validation basis. The results of the ARC software on the measured data are discussed here, and they demonstrate the accuracy of the ARC software on fast spectrum reactors.