We use information from Social Security earnings records to examine the accuracy of survey responses regarding participation in tax-deferred pension plans. As employer-provided defined benefit pensions are replaced by voluntary contribution plans, employees’ understanding of the link between their annual contributions and their post-retirement wealth is becoming increasingly important. We examine the extent to which wage-earners in the Health and Retirement Study (HRS) correctly report their inclusion in tax-deferred contribution plans and, conditional on inclusion, their annual contributions. We use three samples representing different cohorts in three different periods: the original HRS cohort interviewed in 1992 at ages 51–56, the War Babies cohort interviewed in 1998 at ages 51–56, and the Early Baby Boomer cohort interviewed in 2004 at the same ages. Our findings indicate that while respondents interviewed in 1998 and 2004 were more likely to correctly report whether they were included in defined contribution plans, they were no more accurate when reporting whether they had contributed to their plans than respondents interviewed in 1992. Contributors in the three cohorts, moreover, overstated their annual contributions and thus would be likely to realize lower than expected account balances at retirement. The magnitude of this error is not negligible. In all three cohorts, the mean reporting error (the absolute difference between respondent-reported and Social Security earnings record contributions) was approximately 1.5 times larger than the mean contribution in the W-2 earnings record.