Researchers often treat workload as a task-dependent variable. To evaluate the effect of workload on individuals' performance, researchers commonly use several methods, such as varying the complexity or number of tasks that test participants are asked to handle or placing individuals under time constraints. Only rarely have researchers investigated workload as a variable dependent on individuals' cognitive abilities. This study investigated workload during dynamic decision making in terms of its dependence on both task workload and cognitive abilities. The findings demonstrate detrimental effects of both high task workload and low cognitive abilities. Further, the results show that high workload is more detrimental in individuals with low cognitive abilities than in individuals with high cognitive abilities. Potential applications of this research include the design of new workload studies and new training protocols in which psychometric tests are used.