Surveys have often employed two different self-report formats when gathering information on a series of behaviors or events: 1) a yes–no grid format (answer “yes” or “no” if the behavior or event has occurred) or 2) a multiple response list format (“select all that apply”). In a series of five web-based experiments, these two behavioral self-report formats were compared. We found consistent and significant differences – using yes–no grids yielded higher endorsement rates than obtained using multiple response list formats. These differences were obtained regardless of topic or language and country of residence of respondents.