Those discounts are mandated by law.
Yet the administration has stoked more uncertainty than it has allayed, leaving the health system in peril. Some 7 million people qualified for the subsidies in 2017, or about 58% of all Obamacare enrollees.
Democrats pounced on the report as a reason to keep the subsidies in place.
Overall, the number of uninsured people would be slightly higher in 2018 but slightly lower starting in 2020 under the scenario the CBO examined, per the report.
"Ending the payments to insurers would introduce more chaos into an unsettled market, and perversely end up costing the federal government more in the end", said Larry Levitt of the Kaiser Family Foundation, a nonpartisan group that found similar results.
The federal government is projected to spend about $10 billion in subsidies to insurers in 2018.
The payments became the subject of a lawsuit between the Obama administration and the Republican-controlled House in 2015.
A federal judge in 2016 upheld the House's challenge to the legality of the payments. The immediate aftermath of Trump's decision to halt payments could devastate a million or more who receive subsidies. The ruling was stayed pending appeal, and has been on hold since Trump won the presidency.
Most people buying insurance sold on the health care exchanges created by the Affordable Care Act would pay a similar monthly cost to what they pay now despite an initial increase in premiums of about 20%.
The decision will allow insurers to breathe easier in the coming weeks, although companies say they'd like to see President Trump commit to the "cost-sharing reductions" for a longer period, at least through next year. "T$3 he nongroup insurance market would also continue to be stable in most areas of the country", CBO concludes, in part because state insurance commissioners would have significant incentive to approve premium increases. However, it also helps low-income consumers purchase insurance by capping the amount they have to pay in premiums at a specific percentage of their income, and providing tax credits that make up the difference.
But reports this year suggest insurance profits are up and markets are stabilizing.
His committee is scheduled to hold bipartisan hearings on stabilizing the health insurance market the week of September 4.
Without the payments, insurers have said they may drop out of the Affordable Care Act's exchanges or substantially raise premiums. "However, this cat-and-mouse game every month has to stop".
No one knows how the Trump administration will manage ObamaCare, which makes it exceedingly hard for insurers to price their plans.
In July, Trump threatened to end the ACA's cost-sharing reductions that compensate insurance companies for providing low-cost plans to low-income Americans.
House Republicans sued the Obama administration, arguing that under the Constitution, only Congress has the power of the purse, and that Congress was injured as an institution when the Obama administration made the payments without a clear appropriation.