Individuals increasingly face important decisions much later into their life. However, little is known about how aging systematically impacts the quality of these decisions, particularly in middle-aged older individuals between the ages of 45 and 65 relative to younger adults between the ages of 18 and 35. Across two independent studies using a risky-choice task, we found that younger adults preferred options that maximized the overall probability of winning while middle-aged older adults preferred options that maximized the largest gain. Critically, younger adults adapted their decision strategies to systematic changes in trial types, while middle-aged older adults were influenced by task-irrelevant factors like presentation format. Strikingly, these aging effects did not generalize to an annuity task in the second study, where middle-aged older adults demonstrated greater levels of deliberation and lesser susceptibility to task-irrelevant factors when choosing between annuities. Converging process data obtained using eye tracking corroborated these findings. These findings demonstrate that age-related changes in decision strategies across contexts may not always be optimal. This has important implications for generalizing the effects of age across tasks and for the development of interventions that facilitate better decision-making.