Grain residues in nine commercial elevators in Kansas were sampled monthly for insects in grain residues in the boot pit, dump pit, headhouse, rail area, and tunnel. When a grain residue was found, the quantity was estimated, a sample was taken, and adult grain pest insects and beneficial insects were removed and identified. Cryptolestes spp. and Sitophilus spp. comprised about 80% of the pest insects collected. The density of Cryptolestes spp. appeared to rapidly increase in spring but remained low at other times of the year. The density of Sitophilus spp. in the residues increased consistently through the warm months, peaked immediately after the warmest month, and declined gradually as ambient temperatures cooled. Other common stored-grain insects were found sporadically throughout the study. Samples taken from the elevator boot pit and tunnel areas contained a greater density of pest insects (all species combined) compared to other locations. Beneficial insects were observed infrequently, and mean populations exceeded 1 insect/kg of residue in any month at only two of the nine elevators. Results from our study showed that grain residues within the elevator often contain pest insects and could provide food and harborage when the bins are empty and serve as sources of insect infestation for new grain.