Introduction: Racial and economic segregation is associated with poor health outcomes, including out-of-hospital cardiac arrest (OHCA) survival. Prior work identified disparities in OHCA survival for Medicare beneficiaries associated with residential segregation. We sought to use registry data to evaluate this association of racial and economic segregation with OHCA survival to discharge. Methods: We conducted a retrospective analysis of the 2013-2021 Cardiac Arrest Registry toEnhance Survival OHCA dataset. Arrests with missing data, pediatric patients, or EMS-witnessed were excluded. Our primary predictor, the index of concentration at the extremes(ICE), is a validated measure of racial and economic segregation. We examined three ICE measures (race, income, and race + income) calculated from US Census data and binned into tract-level quintiles. The primary outcome was survival to discharge. We performed multi-levelPoisson regression, with hospital random effect, and adjusted for age, gender, race and ethnicity, witness status, location, and bystander CPR to predict relative risk of survival to discharge and good neurological outcome. Results: We identified 624,626 adult OHCA patients with median age 64 years (SD 17), 38%female, 22% Black/African American, 50% White, 6.8% Hispanic/Latino. Overall, 156,712 (25%)survived to hospital admission, 10% survived to hospital discharge and 6.3% had good neurological outcome. Patients residing in the most segregated White and higher income tracts(Q5) had a 7-10% higher likelihood of survival to discharge compared to the most segregatedBlack and lower income communities (Q1) across all three measures (race RR: 1.09, CI 1.05-1.12; income RR: 1.07, CI 1.04-1.10; race + income RR: 1.10, CI 1.06-1.13). Similarly, neurological recovery was higher in Q5 (race RR: 1.20, CI 1.15-1.25; income RR: 1.12, CI 1.08-1.16; race + income RR: 1.19, CI 1.15-1.23) compared to Q1. Conclusion: We identified outcome disparities across three ICE measures for residents of the most segregated and lowest income Black census tracts compared to those in most segregated higher income White census tracts. Future work should focus on interventions for these disparities to improve survival and address health inequities.