Background The health status and health needs of adults with intellectual disability (ID) change with advancing age, and are often accompanied by difficulties with vision, hearing, mobility, stamina and some mental processes. Aim The present study collected health status information on a large cohort of adults with ID aged ≥ 40 years living in small group, community‐based residences in two representative areas of New York State, USA. Method Adult group home residents with ID aged between 40 and 79 years (n = 1371) were surveyed to determine their health status and patterns of morbidity. Results Most subjects were characterized as being in good health. The frequency of cardiovascular, musculoskeletal and respiratory conditions, and sensory impairments increased with age, while neurological, endocrine and dermatological diseases did not. Psychiatric and behavioural disorders declined with increasing age, at least through 70 years of age. Although most conditions increased with age, their frequency varied by sex and level of ID. Frequencies of age‐related organ system morbidity were compared to data from the National Health and Nutrition Evaluation Survey III. It was found that adults with ID had a lower overall reported frequency of cardiovascular risk factors, including hypertension and hyperlipidaemia, and adult‐onset diabetes. Inconsistencies with mortality data among older adults with ID were observed (which showed equal if not greater prevalence of deaths as a result of cardiovascular disease and cancer). Conclusion These results suggest that either a cohort effect is operating (i.e. contemporary populations are healthier than previous populations), or that there may be under‐recognition of select risk factors and diseases.