Understanding the effectiveness of a school closure in limiting social interaction and the economic impact of school closure on households is critical when developing guidelines to prevent spread of pandemic influenza. A New York City survey conducted in June 2009 in 554 households affected by the 2009 pandemic influenza H1N1-related school closures showed that, during closure, 30% of students visited at least 1 locale outside their homes. If all the adults in the home were employed, an ill child was less likely to leave home. In 17% of the households, at least 1 adult missed some work because of the closure. If all adults in the home were employed, someone was more likely to take time off work. If other children were in the household, it was less likely that an adult took time off work. The findings of our study will be important when developing future pandemic school-closure guidance.