Purpose: The objective of this study was to investigate the effect of age on listening effort. Method: A dual-task paradigm was used to evaluate listening effort in different conditions of background noise. Sixty adults ranging in age from 20 to 77 years were included. A primary speech-recognition task and a secondary memory task were performed both separately and simultaneously. Multiple regression analyses were used to evaluate how age and hearing thresholds affect speech recognition and listening effort scores. Results: Results of the multiple regression analyses showed that age is a significant determinant of listening effort, whereby listening effort increases with increasing age even when age-related variance in speech recognition is partialled out. On the basis of the regression equations and the median score for listening effort, it was found that listening effort started to increase in the fourth decade of life. Conclusions: This study was a first exploration of listening effort from young to older adults and showed that, independent of hearing sensitivity, listening effort increases with age. To be more specific, there is a need to further investigate the cognitive functions important for speech communication while exploring their possible relationship with listening effort.