We examined the impact of the Affordable Care Act (ACA) on healthcare coverage, access, health status, and affordability, as well as disparities in these outcomes by race/ethnicity among low-income Californians. We used nationally representative survey data from the Behavioral Risk Factor Surveillance Survey 2011-2019 and a difference-in-differences approach that compared California with nonexpansion states. We examined the impact of Medicaid expansion on health insurance coverage, having a usual source of care, self-reported health status, frequent (≥14) unhealthy days in the past month (physical, mental, and both), and foregone care due to cost. The sample population included low-income Californians (<100% of the federal poverty guidelines) aged 19-64 and low-income childless adults. Low-income adults, childless adults, and white childless adults in California saw post-ACA gains in six of seven outcomes, including a 7.7 percentage point increase in having a usual source of care for all low-income adults (CI: 0.051 to 0.104). Childless adult people of color (POC) reported significant improvements in three measures, with a 6.6 percentage point increase in having a usual source of care (CI: 0.013 to 0.120). All of the groups we examined had coverage gains, ranging from 3.9 percentage points for all low-income adults (CI: 0.013 0.066) to 8.4 percentage points for white childless adults (CI: 0.025 to 0.143). Additionally, all groups reported improved mental health, including an 8.2 percentage point decrease in frequent mental distress for childless adults (CI: -0.120 to -0.044). These findings indicate that the ACA coverage expansion benefitted the targeted population of low-income Californians. Additionally, the disparity between white and non-white Californians decreased for the unadjusted mean rate of having a usual source of care. However, unadjusted means showed that white low-income adults remained more likely to have health insurance coverage and a usual source of care compared with POC in both California and nonexpansion states.