How much to save? Decision costs and retirement plan participation

Deciding how much to save for retirement can be complicated. Drawing on a field experiment conducted with the Department of Defense, we study whether such complexity depresses participation in an employer-sponsored retirement saving plan. We find that simplifying one dimension of the enrollment decision, by highlighting a potential rate at which non-participants might contribute, increases participation in the plan. Similar communications that did not include a highlighted rate yield smaller effects. The results highlight how reducing complexity on the intensive margin of a decision (how much to contribute) can affect extensive margin behavior (whether to contribute at all) in a setting of policy interest.