Jayne O'Donnell

USA TODAY

Repealing the Affordable Care Act's insurance subsidies and mandate to buy insurance would increase the number of uninsured people by 18 million in the following open enrollment year and by 32 million by 2026, the non-partisan Congressional Budget Office said in a report out Tuesday.

The report, done at the request of Senate leaders of both parties, follows Congress' approval last week of a path to repeal portions of the law without Democratic support. CBO analyzed what would happen if reforms to the insurance market remained but the subsidies and mandate were removed, as called for in the budget reconciliation measure that was vetoed by President Obama last January.

The new analysis found that after the ACA's expansion of Medicaid and the subsidies were eliminated, the number of uninsured people would increase to 27 million before it jumped to 32 million.

The predictions were as dire for insurance costs. Premiums for plans purchased on the federal and state insurance exchanges would increase by 20% to 25% above projections for the current law during the first open enrollment year after the new law was enacted. The increase would reach about 50% in the year after Medicaid expansion and subsidies were eliminated, CBO said. By 2026, premiums would double.

Some of the CBO's previous reports on the ACA have been controversial for how far off they were in their projections of ACA enrollment. But it isn't because of any liberal bias.

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The office is now headed by Keith Hall, a conservative former economist in the George W. Bush administration who also worked at the free market Mercatus Center at George Mason University.

Chris Jacobs, a former Republican congressional policy aide, said in a blog post Tuesday, that CBO's earlier miscalculations undercut its new message.

CBO estimated in 2010 that the individual mandate would cause millions more people to sign up for coverage than did. So Jacobs doesn't believe a partial repeal will cause a huge exodus of healthy adults from the marketplace. Even if it did, he favors a broader repeal than that studied by CBO.

"Given their recent track record on this specific issue, should one really take CBO’s word as gospel," wrote Jacobs, who now heads Juniper Research Group

Supporters of the law trumpeted the release, however.

"Today’s non-partisan CBO report details the disastrous impact of the GOP’s efforts to repeal the Affordable Care Act: tens of millions of Americans would lose their healthcare and insurance premiums would skyrocket," said Josh Dorner, a spokesman for the Alliance of Healthcare Security, which includes health care workers and patients who support the ACA. "It’s time for Republicans to show us a plan before they rip apart the healthcare system and rip away the care that millions depend on."

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