The value of Supplemental Nutrition Assistance Program (SNAP) benefits has declined due to inflation since the increase in benefit size in April 2009 mandated by the American Recovery and Reinvestment Act (ARRA). Earlier Economic Research Service (ERS) research documented improvements in food spending and food security from 2008 to 2009 that may have resulted from the ARRA SNAP-benefit increase. This report estimates the extent to which those gains may have been eroded from 2009 to 2011 as a result of the reduction in real value of SNAP benefits due to inflation in food prices. Changes in food spending and food security from 2009 to 2011 were compared between households that did and did not receive SNAP using Current Population Survey Food Security Supplement data. The difference-in-difference analyses, which also adjusted for differences in households’ income, employment, and other characteristics, suggest that the decline in value of SNAP benefits may have resulted in an increase of 16.5 percent in the number of SNAP-recipient households with very low food security and a decline of 4.4 percent in median food spending by SNAP households. The size of these changes relative to the size of the reduction in the inflation-adjusted value of SNAP benefits was consistent with findings from the earlier ERS research on effects of the ARRA SNAP-benefit increase. Taken together, the two studies provide estimates of the effects that may be expected from potential future increases or decreases in SNAP benefits.