Scholars and public health officials have expressed growing alarm over what some have termed a “misinfodemic” − a parallel epidemic of misinformation − around COVID-19. Indeed, conspiracy theories, from the Plandemic pseudo-documentary to QAnon, fuel rising skepticism about scientific facts across many areas of public life, and in recent months especially with respect to COVID-19. Misperceptions, which can rapidly spread from obscurity to mass exposure via social media, may have the capacity to hinder the efficacy of public health efforts aimed at slowing the spread of the pandemic. Especially concerning, encountering false claims online may ultimately reduce the willingness of some Americans to get a COVID-19 vaccine when it becomes available.In this report, we assess respondents’ acceptance of 11 false claims that have circulated online since the beginning of the pandemic. The statements we use include six false claims about conspiracies or risk factors and five false purported preventive treatments for COVID-19. For the conspiracies/risk factors, we asked respondents whether or not they thought each claim was accurate, or whether they were unsure about its accuracy. For the false preventive treatments, we asked participants whether or not they believed the purported treatment was effective, or whether they were unsure about its efficacy.Here, we explore some of the factors associated with higher or lower likelihood of believing false claims. We then consider the association between believing false information about COVID-19 and vaccine acceptance.