<p>Recent growth in the share of household dollars spent on food consumed outside the home, in combination with growing obesity disparities, has heightened interest in food advertising by geography and population demographics. This study aimed to identify changes in advertising expenditure by US restaurant chains across counties, grouped by income, race, and ethnicity, specifically examining whether the lowest income and highest percentage of Black and Hispanic/Latino residents are disproportionately impacted by these trends. Using expenditure and location data for the top-100 grossing US restaurant chains and county-level demographic information, we measured patterns and trends in advertising expenditure at the county level. US counties were split by population density and socio-demographics. Quantile regression analysis was performed to identify baseline differences in total spending within county groups, as well as changes over time. Results show that fast food restaurant chains reported the highest expenditures among the types of restaurants and that the majority of advertising dollars were spent on television advertisements within the highest density counties. Our results show that—for all density types—the lowest levels and the greatest declines of advertising dollars occur among high-income counties and those with a low proportion of Black and Hispanic/Latino residents. Within the lowest density (rural) counties, the highest expenditure rates occurred in counties with a high proportion of Black and Hispanic/Latino residents, regardless of income. Among the highest density (urban) counties, the highest spending levels were observed in low-income counties. Together, these results suggest that restaurant advertising dollars in high- and low-density counties are consistently targeted toward populations who are also at greater risk for obesity in the United States.</p>