Purpose The study was to examine county-level associations of physical activity with COVID-19 cases and deaths, per 100,000 county residents . Methods Data were collected from publicly available data sources for 3142 counties and equivalents, including the District of Columbia . Subjective health ratings, percentage uninsured, percentage unemployed, median household income, percentage female residents, percentage White residents, percentage of residents age 65 or older, and rural designation served as controls . Results The two-level random intercept regression showed that physical activity rates at the county level were statistically and negatively associated with COVID-19 cases and deaths . Additional analyses showed that physical activity rates moderated the relationship between cases and deaths, such that the relationship was strongest when physical activity rates were low . Conclusion The results presented here offer empirical evidence of the benefits of county-level physical activity during a pandemic . Implications for public health and physical activity provision are discussed.