Social Security is the most important and effective income support program ever introduced in the United States, alleviating the burden of poverty for millions of elderly Americans. We explored the possible role of Social Security in reducing mortality among the elderly. In support of this hypothesis, we found that declines in mortality among the elderly exceeded those among younger age groups following the initial implementation of Social Security in 1940, and also in the periods following marked improvements in Social Security benefits via legislation and indexing of benefits that occurred between the mid-1960s and the early 1970s. A better understanding of the link between Social Security and health status among the elderly would add a significant and missing dimension to the public discourse over the future of Social Security, and the potential role of income support programs in reducing health-related socioeconomic disparities and improving population health. © 2011 Macmillan Publishers Ltd.