The Survey of Income and Program Participation (SIPP) has been an important resource for studying the dynamics of SNAP participation. Despite its short recall period relative to other national panel surveys, it is still known to suffer from “seam bias,” in which reports of changes in status (e.g., SNAP participation) occur disproportionately at the seam between interview waves rather than within waves.  This research uses New York state administrative records from 2010 to evaluate the accuracy of reported transitions to and from SNAP in the SIPP.  Transitions are important to policy analysis because estimates of spell length, entry, and exit (and their determinants) are commonly used to explain changes in SNAP participation rates.  A key part of the analysis compares the validity of reported transitions in the current SIPP, in which interviews are conducted every four months, with that in the re-engineered SIPP, in which interviews are conducted annually.