We assess the impact of 401(k) plan design on four different 401(k) savings outcomes: participation in the 401(k) plan, the distribution of employee contribution rates, asset allocation, and cash distributions. We show that plan design can have an important effect on all of these savings...

Economic theory predicts that an unexpected wealth windfall should increase consumption shortly after the windfall is received. We test this prediction using administrative records on over 40,000 401(k) accounts. Contrary to theory, we estimate a negative short-run marginal propensity to consume...

We study a retirement savings plan with a default contribution rate of 12% of income, which is much higher than previously studied defaults. Twenty-five percent of employees had not opted out of this default 12 months after hire; a literature review finds that the corresponding fraction in plans...

If individuals have self-control problems, they may take up commitment contracts that restrict their spending. We experimentally investigate how contract design affects the demand for commitment contracts. Each participant divides money between a liquid account, which permits unrestricted...

What is the socially optimal level of liquidity in a retirement savings system? Liquid retirement savings are desirable because liquidity enables agents to flexibly respond to pre-retirement events that raise the marginal utility of consumption. On the other hand, pre-retirement liquidity is...

Can governments increase private savings by taxing savings up front instead of in retirement? Roth 401(k) contributions are not tax-deductible in the contribution year, but withdrawals in retirement are untaxed. The more common before-tax 401(k) contribution is tax-deductible in the contribution...

Using administrative data from twelve companies that added a Roth 401(k) option between 2006 and 2010, we describe the characteristics of Roth contributions. Approximately one year after the Roth is introduced, 9% of 401(k) participants have positive Roth balances. Roth participation is more...

We conduct and analyze two large surveys of hypothetical annuitization choices. We find that allowing individuals to annuitize a fraction of their wealth increases annuitization relative to a situation where annuitization is an "all or nothing" decision. Very few respondents choose declining...

We study whether prompts to form and recall a plan can increase individuals' responsiveness to reminders to make and attend beneficial appointments. At four companies, all employees due for a colonoscopy were randomly assigned to receive either a control mailing or a treatment mailing. The...

We conducted a field experiment in a 401(k) plan to measure the effect of disseminating information about peer behavior on savings. Low-saving employees received simplified plan enrollment or contribution increase forms. A randomized subset of forms stated the fraction of age-matched coworkers...