question: We sought to characterize gun and ammunition purchasing during the initial phase of the COVID-19 pandemic using a nationally representative sample of U.S. adults. We fielded a survey using NORC's Amerispeak Panel between 7 and 22 July 2020 (survey completion rate = 91.1%, N = 1337). We used survey-weighted data to calculate the proportion of adults who purchased a gun during this time period and types of guns and amount of ammunition purchased. Between March and mid-July 2020, 6% of adults purchased a gun and 9% bought ammunition. Of those purchasing a gun, 34% were first-time purchasers. Among those purchasing ammunition, 19% reported purchasing more than usual in response to the COVID-19 pandemic while 27% purchased less than usual. An estimated 6,451,163 adults bought guns for the first time between March and mid-July 2020. Increases in gun purchasing, particularly among first-time gun owners, could pose significant short- and long-term implications for public health.