Household survey estimates of retirement income suffer from substantial underreporting which biases downward measures of elderly financial well-being. Using data from both the 2016 Current Population Survey Annual Social and Economic Supplement (CPS ASEC) and the Health and Retirement Study (HRS), matched with administrative records, we examine to what extent underreporting of retirement income affects key statistics: elderly reliance on social security benefits and poverty. We find that retirement income is underreported in both the CPS ASEC and the HRS. Consequently, the relative importance of social security income remains overstated – 53 percent of elderly beneficiaries in the CPS ASEC and 49 percent in the HRS rely on social security for the majority of their incomes compared to 42 percent in the administrative data. The elderly poverty rate is also overstated – 8.8 percent in the CPS ASEC and 7.4 percent in the HRS compared to 6.4 percent in the administrative data.