This paper investigates three common differences among DC plans that may lead to varying degrees of information overload. We hypothesize that information overload is one reason DC participants often choose the default options. In two experiments, we manipulate the display of the investment information, the number of choices offered, and the similarity of these choices. In addition, we measure the financial knowledge of the participants. We test how these factors influence the participant’s feelings of information overload, decision satisfaction and choice of the default. The main contribution of this analysis is that it explores the interaction between the individual’s tested financial knowledge and the manipulated plan features. In our study, women with relatively lower salaries and less education tend to fall into our low knowledge category. Our findings do show that changes to plan design can help some individuals. We find individuals with above average financial knowledge do report significantly less overload when given fewer investment choices. This confirms previous research that plan design is important. Our results also show that financial knowledge plays a large role in who opts for the default. We find that low knowledge individuals opt for the default allocation more often than high knowledge individuals (experiment one: 20% vs. 2%). Our findings suggest individuals with below average knowledge are simply overwhelmed by the investment decision in general. Altering the plan by offering investment information in a more easily comparable format or by reducing the choices offered does not attenuate the low knowledge individuals’ feelings of overload. The findings suggest that the success of certain plan features depends strongly on the financial background of the participant. The results emphasize the importance of plan design, especially the careful selection of plan default options, and the need to improve the financial literacy of participants.