We use administrative data on federal civilian workers' accounts in their employer-provided defined contribution plan, called the thrift savings plan (TSP), to provide new evidence on the effects of employer matching and defaults on workers' savings behavior. The empirical analysis relies on exogenous variation stemming from two natural experiments caused by policy changes to the TSP: the establishment of an employer match for workers hired after 1983 and the introduction of automatic enrollment for workers hired after July 2010. We find that the introduction of the employer match lead to a higher increase in both participation and contribution rates compared to the subsequent switch to automatic enrollment. In terms of portfolio allocations, we find that matching and automatic enrollment had small and minimal effects, respectively.
