Offline Electronic Benefit Transfer (EBT) reloading systems were associated with significant relative decreases in WIC participation during the COVID-19 pandemic, driven both by increased WIC participation in online states and decreased WIC participation in offline states. These findings, which may be explained by elevated risks of in-person contact, delays in mail processing, and increased socioeconomic stress during the pandemic, support growing concerns that even seemingly minor barriers to accessing public programs may substantially reduce participation