BackgroundAt the time of this survey, September 1st, there were roughly 6 million COVID-19 cases and 176,771 deaths in the United States and no federally approved vaccine. The objective of this study was to explore the willingness to accept a COVID-19 vaccine in the United States and describe variability in this acceptability by key racial, ethnic and socio-demographic characteristics.MethodsThis was a cross-sectional digital survey that sampled participants from a nationally-representative panel maintained by a third party, Dynata. Dynata randomly sampled their database and emailed web-based surveys to United States residents ensuring the sample was matched to US Census estimates for age, race, gender, income, and Census region. Participants were asked how willing or unwilling they would be to: 1) receive a COVID-19 vaccine as soon as it was made publicly available, and 2) receive the influenza vaccine for the upcoming influenza season. Participants could respond with extremely willing, willing, unwilling, or extremely unwilling. For those who reported being unwilling to receive a COVID-19 vaccine, reasons for this hesitancy were captured. All participants were asked about where they obtain vaccine-related information, and which sources they trust most. Univariable and multivariable logistic regressions were conducted to examine the association of all demographic characteristics with willingness to receive COVID-19 vaccine.FindingsFrom September 1st to September 7, 2020, 1592 respondents completed the online survey. Overall, weighted analyses found that only 58.9% of the sample population were either willing or extremely willing to receive a COVID-19 vaccine as soon as it was made publicly available. In comparison, 67.7% of the respondents were willing or extremely willing to take the influenza vaccine. By gender, 66.1% of males and 51.5% of females were willing to receive a COVID-19 vaccine. Males were significantly more willing to receive a COVID-19 vaccine (adjusted odds ratio (OR)=1.98, 95% CI: 1.56, 2.53; p<0.001) than females. Blacks were the least willing racial/ethnic group (48.8%) Blacks, (aOR=0.59, 95%CI: 0.43, 0.80; p<0.001) were significantly less willing, than whites, to receive a COVID-19 vaccine. There were numerous reasons provided for being unwilling to receive a COVID-19 vaccine. The most common reason was concern about the vaccine’s safety (36.9%), followed by concerns over its efficacy (19.1%).InterpretationIn conclusion, we found that a substantial proportion (41%) of United States residents are unwilling to receive a COVID-19 vaccine as soon as one is made publicly available. We found that vaccine acceptance differs by sub-populations. In addition to sub-group differences in willingness to receive the vaccine, respondents provided a variety of reasons for being unwilling to receive the vaccine, driven by various sources of vaccine information (and misinformation). This compounds the challenge of delivering a safe and efficacious COVID-19 vaccine at a population level to achieve herd immunity. A multi-pronged and targeted communications and outreach effort is likely needed to achieve a high level of immunization coverage.