question: Individuals engage in a variety of behavioral responses to cope with the COVID-19 pandemic, from complying with or transgressing against physical distancing regulations, to stockpiling or prosocial behavior. We predicted that particularly descriptive social norms are important in driving pandemic-related behavior as they offer guidelines in times of insecurity and crisis. To investigate this assumption, we conducted a longitudinal survey with two measurement points (n = 1,907) in Germany during the spring of 2020. Results show that descriptive norms (perceived behavior of close others) positively predicted future transgression against distancing regulations, stockpiling, and prosocial behavior over time. In our analysis, we account for previous behavior as well as other potential predictors (subjective threat, personality). In sum, our findings highlight the power of descriptive norms in increasing compliance with pandemic-related regulations and promoting future prosocial behavior. [ABSTRACT FROM AUTHOR] Copyright of Group Processes & Intergroup Relations is the property of Sage Publications, Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)