The larger grain borer (Prostephanus truncatus [Horn] [Coleoptera: Bostrichidae]) is a wood-boring insect native to Central America but has adapted to stored maize and cassava. It was accidentally introduced to Tanzania and became a pest across central Africa. Unlike many grain pests, P. truncatus populations can establish and move within forested habitats. Consequently, novel infestations can occur without human influence. The objectives of our study were to (1) develop an updated current suitability projection for P. truncatus (2) assess its potential future distribution under different climate change scenarios, and (3) identify climate variables that best inform the model. We used WALLACE and MaxEnt to predict potential global distribution by incorporating bioclimatic variables and occurrence records. Future models were projected to 2050 and 2070 with Representative Concentration Pathways (RCP) 2.6 (low warming) and 8.5 (high warming). Distribution was most limited by high precipitation and cold temperatures. Globally, highly suitable areas (>75%) primarily occurred along coastal and equatorial regions with novel areas in northern South America, India, southeastern Asia, Indonesia, and the Philippines, totaling 7% under current conditions. Highly suitable areas at RCP 2.6 and 8.5 are estimated to increase to 12 and 15%, respectively, by 2050 and increase to 19% in 2070 under RCP 8.5. Centroids of highly suitable areas show the distribution centers move more inshore and away from the equator. Notably, the result is a range expansion, not shift. These results can be used to decrease biosecurity risks through more spatially explicit and timely surveillance programs for targeting the exclusion of this pest.