The uninsured rate for working-age adults has declined in every single state since 2013, according to the Commonwealth Fund. The largest declines were in states that expanded Medicaid to cover low-income adults. Some of those states, including Kentucky and West Virginia, cut their uninsured rate in half in two years.
Republican leaders in the Carolinas chose not to expand Medicaid. But Commonwealth Fund Vice President Sara Collins says those states benefited from the other big change that kicked in in 2014 - the first year of the online exchanges or marketplaces.
"Because people were able to get coverage through the marketplaces and get a subsidy to help them pay for that coverage, those states that didn't expand eligibility also saw pretty significant declines," says Collins. "We've also seen in North Carolina a decline in the percentage of people who report they didn't get care because of the cost of the care."
South Carolina had a similar improvement in that category.
The uninsured rate is down to 16 percent in both North and South Carolina, compared to 13 percent nationally. The biggest insurance gains in the Carolinas were among African-Americans and Hispanics.
This picture could change dramatically if Republicans in Washington fulfill their promise of repealing Obamacare. Without a replacement, Collins says uninsured rates will shoot back up.