The controversial process set up to resolve disputes between payers and providers over out-of-network bills continues to snowball, according to new federal data.
Between July and December last year, providers and payers initiated almost 1.4 million disputes through a federal portal meant to handle billing challenges under the No Surprises Act, 16% more than the first half of 2025, according to federal data released Wednesday.
The NSA was passed in 2020 to protect patients from unexpected medical bills. To do so, the law created the independent dispute resolution process, where providers and payers submit what they think is a fair price for out-of-network care, and an independent arbiter certified by the government chooses between the two offers.
The law has been successful in shielding consumers from surprise bills. But IDR has been dogged by an unexpectedly high number of disputes and complaints from both insurers and providers, who say the process unfairly favors the other side.
Insurers have been particularly vocal, arguing the dispute resolution process is being exploited by providers to gin up significantly higher payments. Data released by the CMS to date appears to back up that position, and the latest release was no different, as providers continued to dominate the surprise billing dispute resolution process in the second half of 2025 and win the majority of challenges.
Providers or their representatives initiated 76% of disputes during the period, and were the prevailing party in about 85% of cases, according to the CMS.
Most disputes were launched by a small group of providers: The top 10 initiating parties made up about 66% of all disputes in the last six months of last year, down slightly from 69% in the first half of the year.
The top three initiating companies — billing intermediary HaloMD and provider groups Team Health and SCP Health — accounted for about 38% of all disputes in the second half of 2025.
HaloMD has been sued by several insurers for allegedly gaming the arbitration process, though federal judges have thrown out a number of the cases, arguing the courts don’t have authority to intervene.
Providers continue to rake in more money under No Surprises than they would have received for providing in-network care, according to the CMS.
The winning offer was higher than the qualifying payment amount — the median contracted rate for a service in a given area — in about 87% of payment decisions in the last six months of 2025.
Overall, total payouts under No Surprises reached almost $15 billion in 2025, more than triple the year prior, according to a Wall Street Journal analysis of the CMS data.
The quick growth is concerning. Health economists say the inflated payouts could lead to higher premiums for Americans and their employers, and drive up the nation’s overall healthcare spending.
The $15 billion sum is more than six times the amount providers would have been paid if the disputed care had been delivered in-network, according to the WSJ’s analysis. A CMS spokesperson acknowledged problems with the situation.
“While patients are now protected from surprise bills, the system is being gamed to get higher prices, and CMS is actively working to clean it up,” they told the WSJ.
The spokesperson did not provide details. However, this spring, the Trump administration finalized a rule patching shortcomings in the IDR process, including cutting down on ineligible disputes and standardizing communication between payers and providers.
Insurers say the rule did not go far enough, and have continued to lobby Congress to reform No Surprises.
“Extreme IDR award after extreme IDR award is now the norm. Congress and the Trump administration cannot delay in overhauling the IDR system that is in desperate need of reform,” the Coalition Against Surprise Medical Billing, an advocacy group backed by insurers and employers, said in a statement on the new CMS data.
Still, arbiters are getting better at handling their caseloads and tackling the backlog of disputes, regulators said. By the end of the year, nearly all disputes submitted since the program began in 2022 had been resolved or were less than 30 days old.
Certified IDR entities closed 7% more challenges in the second half of the year compared with the first half, thanks in part to increased capacity after regulators onboarded two new arbiters that began receiving cases in September.
Arbiters are also making decisions more quickly. About 62% of payment determinations were rendered within 30 business days during the last six months of 2025, compared with 37% in the first half of the year.
“Certified IDR entities have achieved remarkable improvements in throughput and processing speed over time and have closed the vast majority of the dispute backlog while keeping pace with rising dispute volume,” regulators wrote. “The resolution of aged disputes marks significant improvement in the efficiency of the IDR process.”
Still, there are plenty of challenges, particularly the complexity of determining whether disputes are actually eligible for IDR, the CMS said. Parties that didn’t initiate the dispute challenged the eligibility of 42% of claims in the second half of the year, up from 40% in the first six months of 2025.
Process improvements and increased familiarity among disputing parties about eligibility have likely helped decrease the number of ineligible challenges, regulators said. About 69% of disputes were found eligible in the first six months of 2022, falling to 19% in the last six months of last year.
Rebecca Pifer Parduhn contributed to this story.
