INTRODUCTION Identifying those at heightened risk of severe illness from novel coronavirus disease 2019 (COVID-19) is essential for modeling disease, designing return-to-work criteria, allocating economic assistance, advancing health equity, and limiting morbidity and mortality. The U.S. Centers for Disease Control and Prevention has identified criteria associated with risk of severe complications from COVID-19 infection (Appendix Table 1). 1 Structural inequities have shaped racial, ethnic, and income disparities for many of these criteria. To date, there has been limited analysis of the proportion of the population at risk in the U.S. based on these criteria, 2 or risk factors by race/ethnicity or income. Preliminary national data on cases by race/ethnicity suggest that disparities in hospitalization are already developing. 3 Quantifying disparities in risk is important for allocating resources to prevent, identify, and treat COVID-19-related severe illness and limit diverging outcomes for already vulnerable subgroups. METHODS The authors used data from the 2018 Behavioral Risk Factor Surveillance System, a nationally representative survey of >400,000 adults. This study estimated the proportion of adults that have at least one of the Centers for Disease Control and Prevention criteria for risk of severe illness from COVID-19 (hereafter “higher risk”) (Appendix Table 1) by age group, and by race/ethnicity and household income ( 65 years (63% vs 52%, PR=1.21, 95% CI=1.18, 1.24) (Appendix Table 9). DISCUSSION People who are black, American Indian, or live in low-income households are more likely to have conditions associated with increased risk of illness from COVID-19 relative to those who are white or higher income, respectively. These inequities in risk are compounded by structural disparities in access to medical insurance, 4 wealth, and income volatility. 5 Structural inequities also contribute to heightened exposure to COVID-19. Minorities and people living in low-income households are more likely to work in industries that have remained open during non-essential business closures. 6 They are also more likely to live in crowded conditions 7 and multigenerational households that may elevate exposure and limit options for quarantining family members. It is vital that these race/ethnicity and income disparities in risk be considered in physical distancing policies and other protective measures, particularly for those who work in essential industries. Rationing resources based on comorbidities may exacerbate inequities, whereas prioritizing vaccine delivery on risk may reduce deaths and disparities. Data availability in the Behavioral Risk Factor Surveillance System is a limiting factor; the data do not include all risk criteria and only capture respondents who were aware of their condition. These estimates represent a lower bound of adults at risk of severe illness. It is possible that risk is not uniform and those with multiple factors may be at higher risk. This would be further evidence of race/ethnicity and income disparities.