That was an estimated $7.4 billion, or 21 percent less, than the $34.7 billion in uncompensated costs that hospitals would have incurred if health coverage levels had remained at the levels seen in 2013, before Obamacare took full effect, the department said.
But most of those reduced costs—$5 billion—came in the 28 states and the District of Columbia that expanded their Medicaid programs to cover nearly all poor people. Hospitals in those states had a 26 percent reduction in uncompensated care spending, and realized 68 percent of the total savings, HHS said.
The remaining $2.4 billion in reduced uncompensated costs came in states that have tighter restrictions on who qualifies for Medicaid, which is jointly run by the federal government and states. Hospitals in nonexpansion states had a 16 percent reduction in uncompensated care costs, and realized 32 percent of the total savings.
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HHS said, "If nonexpansion states had proportionately as large increases in Medicaid coverage as did expansion states, their uncompensated care costs would have declined by an additional $1.4 billion."
The reduction in uncompensated care costs came in the first year to see the full effect of Obamacare's two major programs: the sale of often-subsidized private health insurance on government-run health exchanges, and the expansion of Medicaid to cover people who earn less than 138 percent of the federal poverty line. Last year was also the first that nearly all Americans were required to have some form of health coverage or be subject to a tax penalty.
Medicaid expansion was originally supposed to happen across the U.S., but a Supreme Court ruling in 2012 left the decision on whether to expand up to individual states.
About 6.7 million people were enrolled in Obamacare plans by the end of 2014. And last week, the government said that as of January, about 11.2 million additional people were enrolled in Medicaid compared to the average monthly enrollment in Medicaid seen in the month before the October 2013 launch of the Obamacare exchanges.