In general, research on aging and decision-making has grown in recent years. Yet, little work has investigated how reliance on classic heuristics may differ across adulthood. For example, younger adults rely on the availability of information from memory when judging the relative frequency of plane crashes versus car accidents, but it is unclear if older adults are similarly reliant on this heuristic. In the present study, participants aged 20–90 years old made judgments that could be answered by relying on five different heuristics: anchoring, availability, recognition, representativeness, and sunk-cost bias. We found no evidence of age-related differences in the use of the classic heuristics—younger and older adults employed anchoring, availability, recognition, and representativeness to equal degrees in order to make decisions. However, replicating past work, we found age-related differences in the sunk-cost bias—older adults were more likely to avoid this fallacy compared to younger adults. We explain these different patterns by drawing on the distinctive roles that stored knowledge and personal experience likely play across heuristics.