Purpose: Listening-related fatigue is a potential negative consequence of challenges experienced during everyday listening and may disproportionately affect older adults. Contrary to expectation, we recently found that increased reports of listening-related fatigue were associated with better performance on a dichotic listening task. However, this link was found only in individuals who reported heightened sensitivity to a variety of physical, social, and emotional stimuli (i.e., increased "sensory-processing sensitivity" [SPS]). This study examined whether perceived effort may underlie the link between performance and fatigue. Method: Two hundred six young adults, aged 18-30 years (Experiment 1), and 122 older adults, aged 60-80 years (Experiment 2), performed a dichotic listening task and were administered a series of questionnaires including the NASA Task Load Index of perceived effort, the Vanderbilt Fatigue Scale (measuring daily life listening-related fatigue), and the Highly Sensitive Person Scale (measuring SPS). Both experiments were completed online. Results: SPS predicted listening-related fatigue, but perceived effort during the listening task was not associated with SPS or listening-related fatigue in either age group. We were also unable to replicate the interaction between dichotic listening performance and SPS in either group. Exploratory analyses revealed contrasting effects of age; older adults found the dichotic listening task more effortful but indicated lower overall fatigue. Conclusions: These findings suggest that SPS is a better predictor of listening-related fatigue than performance or effort ratings on a dichotic listening task. SPS may be an important factor in determining an individual's likelihood of experiencing listening-related fatigue irrespective of hearing or cognitive ability.