In the South, people living with HIV experience worse health outcomes than in other geographic regions, likely due to regional political, structural, and socioeconomic factors. We describe the neighborhoods of women (n = 1,800) living with and without HIV in the Women's Interagency HIV Study (WIHS), a cohort with Southern sites in Chapel Hill, NC; Atlanta, GA; Birmingham, AL; Jackson, MS; and Miami, FL; and non-Southern sites in Brooklyn, NY; Bronx, NY; Washington, DC; San Francisco, CA; and Chicago, IL. In 2014, participants' addresses were geocoded and matched to several administrative data sources. There were a number of differences between the neighborhood contexts of Southern and non-Southern WIHS participants. Southern states had the lowest income eligibility thresholds for family Medicaid, and consequently higher proportions of uninsured individuals. Modeled proportions of income devoted to transportation were much higher in Southern neighborhoods (Location Affordability Index of 28-39% compared to 16-23% in non-Southern sites), and fewer participants lived in counties where hospitals reported providing HIV care (55% of GA, 63% of NC, and 76% of AL participants lived in a county with a hospital that provided HIV care, compared to >90% at all other sites). Finally, the states with the highest adult incarceration rates were all in the South (per 100,000 residents: AL 820, MS 788, GA 686, FL 644). Many Southern states opted not to expand Medicaid, invest little in transportation infrastructure, and have staggering rates of incarceration. Resolution of racial and geographic disparities in HIV health outcomes will require addressing these structural barriers.