We examine SNAP’s effectiveness as an antipoverty weapon. We estimate the extent to which SNAP has reduced the prevalence of poverty, and also its depth and severity, and the amount of benefits which spill over beyond the poverty line, from 1979-2011.  Finally, we discuss the primary challenge to getting an accurate measure of SNAP’s antipoverty effect, and how the design of the program influences that effect.

Since SNAP benefits are not included in the official U.S. poverty estimation, the program’s role in reducing poverty is not reflected in official poverty statistics. We calculate the reduction in the prevalence and depth of official poverty due to SNAP benefits over the past 25 years, to understand how the program’s antipoverty effect varies with changes in economic conditions and in program design and administration. We also examine two additional Census Bureau poverty measures that provide a more comprehensive picture of family well-being. We estimate the effect of SNAP on the experimental poverty measures from 2002 to 2011, to estimate SNAP’s effect on poverty over a recent period of signification caseload growth, and on the more recently developed Research Supplemental Poverty (SPM) measure.

SNAP has very few nonfinancial eligibility restrictions and is intended to reach a broad range of disadvantaged households. We examine the breadth of SNAP’s antipoverty effect, by focusing on vulnerable populations such single-parent families, the elderly, and immigrants. In addition, because SNAP can be an important resource for both the working poor and the unemployed, we assess the program’s antipoverty effect among these two groups. We also estimate the extent to which SNAP benefits alleviate the intensity of poverty in the U.S. Families with lower incomes receive larger benefits than similar families with higher incomes. Larger benefits certainly reduce hardship for the poorest families but may not lift them out of poverty. We estimate how many families are lifted out of deep poverty, defined as income below 50% of the poverty line, by SNAP benefits. We also estimate the effect of SNAP benefits on two measures—the poverty gap and squared poverty gap indices—that convey the depth and severity of poverty. We discuss the implications of underreporting on measuring SNAP’s antipoverty effect and efforts to correct for underreporting.

We conclude with a discussion of two features of SNAP expected to influence the magnitude and distribution of the program’s antipoverty effect. The first is that SNAP maximum benefits are uniform nationwide, which means that the antipoverty effect of the program may be muted in areas with higher food costs. We consider whether the program should provide a supplement for areas with high food costs. The second is that states have been given increased flexibility since the mid-1990s in how they administer the program. For example, many states no longer place a limit on assets when calculating a household’s SNAP eligibility. We consider whether this and other specific state policy choices have increased the antipoverty effect of the program, and whether these policies should be adopted nationwide.