Black, Latino, Pacific Islander, and American Indian/Alaska Native adults are more likely than White adults to experience SARS-CoV-2-related infections, hospitalizations, and mortality. We assessed intent to be vaccinated and concerns among 7 U.S. racial/ethnic groups (1,000 Black/African American, 500 American Indian/Alaska Native, 1,000 Asian, 1,000 Latino (500 English- and 500 Spanish-speaking), 500 Pacific Islander, 500 multiracial, and 1,000 White adults) in a cross-sectional online survey conducted December 2020-February 2021, weighted to be nationally representative within groups. Intent to be vaccinated was ascertained with: "If a COVID-19 vaccine becomes available, how likely are you to get vaccinated?" (not at all/slightly/moderately/very/extremely likely). Respondents identified which concerns would keep them from being vaccinated: cost, not knowing where, safety, effectiveness, side-effects, and other. Multinomial logistic regression models assessed associations of race/ethnicity with odds of being extremely/very/moderately, slightly likely to be vaccinated (ref = not at all), controlling for demographics and health. Overall, 30% were extremely likely, 22% not at all likely, and 48% unsure. Compared to White respondents, American Indian/Alaska Native (Adjusted Odds Ratio (AOR) = 0.66, 95% CI, 0.47-0.92) and Black/African American (AOR = 0.54, 95% CI, 0.41-0.72) respondents were less likely, and Asian (AOR = 2.21, 95% CI, 1.61-3.02) and Spanish-speaking Latino respondents (AOR = 3.74, 95% CI, 2.51-5.55) were more likely to report being extremely likely to be vaccinated. Side-effects (52%) and safety (45%) were overriding concerns. Intent and vaccination rates are changing rapidly; these results constitute a comprehensive baseline for ongoing vaccination efforts among U.S. racial and ethnic groups.