Undetected/untreated hearing loss imposes significant limitations upon individuals with intellectual disabilities (ID). It can interfere with cognitive development, impede communicative and social interactions, and limit vocational aspirations. Over the past decade, the hearing of 9961 people with ID was evaluated at Special Olympics sports events. This report provides outcome findings. A striking 24% of hearing loss is revealed, 1.4 times greater than the general population of similar ages (18 to 55 years). Most hearing loss is previously undetected, unserved or undertreated. Thirteen percent have sensorineural hearing losses, and most could benefit from hearing aids. An additional 11% show conductive/mixed losses needing medical attention. These outcomes highlight the need for parents, caregivers, primary care physicians, other healthcare providers and teachers to be informed about high incidences of hearing loss among people with ID, to advocate for annual hearing evaluations, and to assure immediate interventions once hearing loss is identified. (Contains 2 figures and 2 tables.)