In the near future, workforces will increasingly consist of older workers. At the same time, research has demonstrated that work-related growth motives decrease with age. Although this finding is consistent with life span theories, such as the selection optimization and compensation (SOC) model, we know relatively little about the process variables that bring about this change in work motivation. Therefore, we use a 4-wave study design to examine the mediating role of future time perspective and promotion focus in the negative association between age and work-related growth motives. Consistent with the SOC model, we found that future time perspective was negatively associated with age, which, in turn, was associated with lower promotion focus, lower work-related growth motive strength, and lower motivation to continue working. These findings have important theoretical implications for the literature on aging and work motivation, and practical implications for how to motivate older workers.