With the second round of open enrollment now underway, the Affordable Care Act is expected to help narrow racial and ethnic disparities in insurance coverage, a new report finds. However, not all communities are predicted to benefit equally. Because nearly half of the country’s legislatures decided against expanding Medicaid eligibility, black Americans may continue to face difficulties finding quality, affordable health coverage.

This month, the Urban Institute’s Health Policy Center released a new report detailing racial and ethnic differences in insurance rates under the ACA. Using data from the American Community Survey, report authors used a simulation model to estimate rates of uninsurance in 2016 among five racial and ethnic groups: whites, Hispanics, Asians, blacks and American Indians/Alaska Natives. Estimates were then calculated for three different insurance scenarios: coverage without the ACA; coverage with the ACA and under current Medicaid expansions; and coverage under the ACA with all states expanding Medicaid eligibility. (At the time of the ACA’s passage, the law set a nationwide standard for Medicaid eligibility, expanding the program’s criteria to cover adults with family income up to 138 percent of the poverty level. Unfortunately, in 2012, the Supreme Court ruled that states could decide against expanding Medicaid. Today, 27 states and Washington, D.C., have either expanded Medicaid eligibility or plan to do so.)

The Urban Institute report predicts large reductions in uninsured rates for all racial and ethnic groups under the current Medicaid expansion map and predicted even larger reductions if every state expanded Medicaid. The gains narrow insurance coverage disparities between whites and each of the minority groups, except for blacks, as large numbers of black Americans live in states where policymakers oppose Medicaid expansion. However, under a scenario in which all states expand Medicaid, blacks are predicted to experience a “marked reduction” in uninsurance rates, and the coverage disparity between blacks and whites would significantly narrow. (Because some states haven’t expanded Medicaid, many Americans fall into a new coverage gap, in which they don’t qualify for Medicaid and they don’t quality for subsidies in the new health insurance marketplace.) Report authors Lisa Clemans-Cope, Matthew Buettgens and Hannah Recht write:

For uninsured individuals, where you live matters. The ACA, through Medicaid expansion, is likely to reduce longstanding racial/ethnic differences in health insurance coverage between whites and minorities. But for those living in nonexpansion states, health insurance coverage remains out of reach.

Specifically, under the ACA with current Medicaid expansions, American Indians and Alaska Natives are predicted to experience a decrease in uninsurance rates from 25.7 percent to 13 percent (a nearly 50 percent reduction with 600,000 people gaining insurance coverage). Hispanics are projected to experience a decrease in uninsurance rates from 31.2 percent to 19 percent (a more than 39 percent reduction with 6.6 million people gaining coverage). In addition, uninsurance among whites would decrease more than 51 percent, from just more than 13 percent without the ACA to 6.3 percent under the ACA and current Medicaid expansions — overall, 11.1 million whites would gain coverage. Not surprisingly, if legislatures in all states decided to expand Medicaid eligibility, gains in coverage as well as declines in insurance disparities between whites and blacks are predicted.

The report predicts that if all states were to expand Medicaid, uninsurance rates among blacks would decline from 11.3 percent (the rate under the current Medicaid map) to 7.2 percent (the rate under a fully expanded Medicaid map). Today, 1.4 million blacks fall into the ACA coverage gap, which translates into just more than 23 percent of the nation’s uninsured black adult population, the report stated. In addition, if all states expanded Medicaid under the ACA, nearly 14 million whites would gain coverage (a nearly 65 percent reduction in the uninsured rate); 7.8 million Hispanics would gain coverage (a nearly 47 percent reduction); 4.3 million blacks would gain coverage (a more than 63 percent reduction); 1.4 million Asians and Pacific Islanders would get insurance (a more than 53 percent reduction); and 787,000 Americans Indians and Alaska Natives would gain coverage (a more than 61 percent reduction).

But like the authors said above, place matters when it comes to insurance coverage. For example, the authors wrote in a blog article that in St. Louis, just more than 20 percent of black residents are predicted to go without insurance without the ACA — a rate that falls to 14.8 percent under the ACA with current Medicaid expansion and to 7.5 percent if Missouri lawmakers expanded Medicaid eligibility. In comparison, in the St. Louis area that falls within the Illinois state line, only 5.3 percent of black residents are predicted to remain without health insurance under ACA and the state’s decision to expand Medicaid.

To download a full copy of the Urban Institute report and access an interactive map that illustrates insurance coverage under the different scenarios, click here.

Kim Krisberg is a freelance public health writer living in Austin, Texas, and has been writing about public health for more than a decade.