Purpose: Despite well-documented associations of socioeconomic status with incident heart failure (HF) hospitalization, little information exists on the relationship of socioeconomic status with HF diagnosed in the outpatient (OP) setting. Methods: We used Poisson models to examine the association of area-level indicators of educational attainment, poverty, living situation, and density of primary care physicians with incident HF diagnosed in the inpatient (IP) and OP settings among a cohort of Medicare beneficiaries (n = 109,756; 2001–2013). Results: The age-standardized rate of HF incidence was 35.8 (95% confidence interval [CI], 35.1–36.5) and 13.9 (95% CI, 13.5–14.4) cases per 1000 person-years in IP and OP settings, respectively. The incidence rate differences (IRDs) per 1000 person-years in both settings suggested greater incidence of HF in high- compared to low-poverty areas (IP IRD = 4.47 [95% CI, 3.29–5.65], OP IRD = 1.41 [95% CI, 0.61–2.22]) and in low- compared to high-education areas (IP IRD = 3.73 [95% CI, 2.63–4.82], OP IRD = 1.72 [95% CI, 0.97–2.47]). Conclusions: Our results highlight the role of area-level social determinants of health in the incidence of HF in both the IP and OP settings. These findings may have implications for HF prevention policies.