Research and Review of the Extent and Nature of Underreporting of SNAP Participation in National Surveys

Project Overview

This project assessed underreporting of Supplemental Nutrition Assistance Program (SNAP) participation in four national surveys—the Current Population Survey (CPS), the Survey of Income and Program Participation (SIPP), the National Health and Nutrition Examination Survey, and the American Community Survey—to identify potential remedies for the problem. Underreporting has plagued household survey estimates of participation in SNAP and other programs that serve low-income populations, and evidence suggests the problem is worsening. Because of the substantial number of people participating in SNAP and the large share of their income represented by the benefit, it is important the datasets used to study poverty and the potential impacts of changes to program policy provide an accurate accounting of SNAP participation and benefit levels.

For this project, Insight—

  • Reviewed the literature on underreporting in SNAP, other nutrition assistance programs, and other major assistance programs that serve populations with low incomes
  • Prepared estimates of underreporting of SNAP participation using the most recent data from the four national surveys
  • Conducted additional analysis of the survey data to examine variation in underreporting by household characteristics, patterns of SNAP use, and aspects of questionnaire design and administration
  • Prepared a final report combining the research review and empirical findings and discussing possible next steps

Additional analysis of patterns of underreporting focused on the substantial decline in reporting of SNAP participation in the CPS; differences in the characteristics of reported SNAP participants in the SIPP, which had the lowest underreporting by far, and for the other three surveys; and comparisons of the characteristics of SNAP participants recorded in SNAP Quality Control data and those reported in each of the four surveys.


Final report, The Extent and Nature of Underreporting of SNAP Participation in Federal Surveys (July 2012)