Geriatric depression has been associated with cognitive impairments, but whether suboptimal effort contributes to these deficits is unknown. This study investigated differences in cognitive functioning between depressed and nondepressed elderly veterans, before and after excluding patients who provided suboptimal effort on testing at a memory disorders clinic. Patients diagnosed with a depressive disorder performed more poorly than nondepressed patients on almost all Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) indices, but these differences became nonstatistically significant after excluding patients who provided suboptimal effort. However, when patients were classified as normal, mildly, or severely depressed based on Geriatric Depression Scale scores, these groups were not significantly different on RBANS indices, regardless of whether patients who provided suboptimal effort were included or excluded from analyses. The findings suggest that cognitive deficits in depression reported in previous research may be attributable to suboptimal effort and that identifying depression via clinical diagnosis or psychometric data may affect this trend.