By Jack Hoadley, Kennah Watts, and Zachary Baron
The No Surprises Act (NSA) protects consumers from surprise out-of-network (OON) billing by banning providers and facilities from balance billing consumers for many facility-based OON medical services. Services subject to the law include most emergency services, non-emergency services from OON providers at in-network facilities, and services from OON air ambulance providers.
Under the law, the payer must make a timely payment (or a denial of coverage) to the OON provider. If the provider finds the payment amount inadequate and the parties do not privately reach an agreement, either party can request an independent dispute resolution (IDR), in which a third-party arbitrator (“IDR entity”) binds both parties to either the plan or provider offer.
In 2024, in compliance with NSA requirements, the relevant federal agencies released public use files (PUFs) with data on the resolved IDR cases for 2023. In March 2025, the agencies released PUFs for the first two quarters of 2024. These files include information on the provider and payer, as well as offer amounts from each party––expressed as a percentage of a qualifying payment amount (QPA), the inflation-adjusted median rate paid by a specific insurer in 2019 to its contracted in-network providers, based on insurance type and geographic location. The files also include information on the prevailing offer, as determined by the IDR entity.
In this article, we build on our findings from 2023 with analysis from the first two quarters of 2024. We illustrate trends in the IDR process across provider and payer types, offer amounts, geographic locations, IDR entities, and more. We also explore potential implications for the future use and cost of the IDR process. As relevant, we share findings from the agencies’ supplemental tables, from our own analysis of the PUFs, and from discussions with stakeholders.
Rapid Rates Of New Case Filings; More Decisions Emerging From IDR Entities
The volume of filed IDR cases remained high. The six-month total for filed cases (586,581) in Q1 and Q2 of 2024 is nearly as high as all of 2023 (657,040 filed cases), though this may be partly due to periods in 2023 when the IDR portal was suspended.
Exhibit 1. Number of Filed IDR Cases and Share Initiated by Provider Groups, Q1-Q4 2023 and Q1-Q2 2024
Source: Authors’ analysis of Federal IDR Supplemental Tables for 2023 and 2024
The rate of filed cases challenged as ineligible was higher in Q1 and Q2 of 2024 (45 percent) than in all of 2023 (37 percent), but the rate of closed cases later found ineligible was somewhat lower: about 18 percent in 2024 versus 22 percent in 2023. Cases may be ineligible based on the dates of service, whether a case is covered by the NSA, or the need to go through a state payment determination process in certain states.
In 2024, the pace of IDR entity decision-making accelerated substantially. About 335,000 payment determinations were made in Q1 and Q2 of 2024, compared to about 200,000 cases in all of 2023. The volume in the second quarter of 2024 was also well above that in the first quarter. Notably, about one in six determinations are made in cases where only one party submitted an offer—a rate that has remained generally steady from 2023 to 2024. Discussions with stakeholders suggested that this outcome may be the result of plans being overwhelmed by case volume and unable to respond before deadlines.
Cases Remain Concentrated In A Few States
IDR use remained highly concentrated by geography. States with high volumes of resolved cases were generally the same as in 2023: Texas, Florida, Arizona, Tennessee, Georgia, New Jersey, and New York. By contrast, several large-population states (Maryland, Massachusetts, and Washington) had fewer than 2,000 resolved cases in the first two quarters of 2024.
Providers were most successful in Texas, Florida, Arizona, and Virginia, with win rates between 89 percent and 91 percent of resolved cased in Q1 of 2024. This geographic concentration is likely somewhat attributable to high concentrations of the provider organizations that most frequently used IDR. For example, across most quarters, more than half of the cases in Texas involved Radiology Partners affiliated providers. Similarly, two-thirds of Tennessee and Florida cases involved Team Health.
Providers Continue To See More Success Than Plans
Providers continue to win far more often and at much higher offer amounts than plans. In 2023, the rate of providers prevailing rose from 70 percent of resolved cases in Q1 to 87 percent in Q4. Rates in 2024 matched the latter levels: providers won 88 percent and 83 percent of resolved cases in Q1 and Q2, respectively (Exhibit 2).
Exhibit 2. Percent of Resolved IDR Cases Won by Providers, Q1-Q4 2023 and Q1-Q2 2024
Source: Authors’ analysis of Federal IDR PUFs, Reporting Year 2023 and 2024.
Not only do providers win far more often, but their prevailing offers are much higher than plans. In Q1 of 2024, the median prevailing provider offer was 383 percent of QPA. This rose nearly 70 percentage points in Q2, with a median prevailing provider offer of 447 percent of QPA. By contrast, the comparable rates in 2023 were between 320 percent and 350 percent. In cases where plans prevailed, their median offer amount was much lower: 105 percent of QPA in both Q1 and Q2 of 2024.
Large Provider Groups Continue To Prevail At High Rates; Third-Party Entities Emerge
As in 2023, resolved IDR cases were predominantly from a few large provider organizations – mostly backed by private equity. Radiology Partners was the most frequent user of IDR in Q1 and Q2 of 2024, followed by Team Health, SCP Health, AGS Health, and HaloMD. Combined, these five organizations account for nearly two-thirds (63 percent) of resolved cases (Exhibit 3).
Exhibit 3. Share of Resolved IDR Cases by Top Provider Organizations, Q1-Q2 2024
Source: Authors’ analysis of Federal IDR PUFs, Reporting Year 2024.
In addition to a high volume of cases, these top five provider organizations won the vast majority of their disputes, with offer amounts at least two times greater than QPA. Radiology Partners significantly outmatched other provider groups, with a median prevailing offer at 631 percent of QPA and 610 percent of QPA in the first half of 2024.
While the activity level of Radiology Partners, Team Health, SCP Health, and AGS Health remained relatively stable from 2023 to 2024, HaloMD has emerged as a frequent participant in IDR cases. In 2023, HaloMD appeared in only 1 percent of resolved disputes, whereas in Q2 of 2024, HaloMD initiated 10 percent of disputes. HaloMD’s prevailing offers increased substantially as well: in Q1 of 2023, the organization prevailed in 17 percent of resolved cases, but their win rate steadily increased to 84 percent in Q4 of 2023. This success rate appears stable, reaching 89 percent and 81 percent in Q1 and Q2 of 2024.
HaloMD was specifically created “to be the leading provider of IDR services.” HaloMD illustrates the rise of profit enhancing middlemen focused on the IDR process. Whereas large provider organizations like Radiology Partners and Team Health have the internal resources to manage disputes on behalf of their providers, HaloMD and other third-party organizations can take on the administrative burden for smaller providers and offer them a greater opportunity to engage in IDR. As a provider group familiar with the IDR process wrote in a previous Forefront piece, “smaller practices have less ability to access IDR than do larger, well-capitalized organizations.” This trend might be changing with the rise of IDR-specific middlemen.
Emergency And Radiology Services Account For Two-Thirds Of Resolved IDR Cases
The median prevailing offers relative to QPA in Q1 and Q2 of 2024, by provider specialty, generally match or exceed those in 2023 (Exhibit 4). For most specialties, the median percentage of QPA grew across the four quarters of 2023.
Exhibit 4. Median Prevailing Offer among Resolved IDR Cases as Percent of QPA by Specialty, Q1-Q4 2023 and Q1-Q2 2024
Source: Authors’ analysis of Federal IDR PUFs, Reporting Year 2023 and 2024.
Radiology and emergency services are the two specialties with the highest volume of resolved cases, accounting for about two-thirds of all determinations (not shown). In the first half of 2024, the median prevailing offer for emergency services was 257 percent of QPA, a more than 30 percentage point increase from 224 percent in Q4 of 2023. Radiology services experienced a similar increase in win amounts: in the first half of 2024, the median prevailing offer in radiology cases was 40 percentage points more than the end of 2023 (600 percent QPA and 559 percent QPA, respectively). These specialties are closely correlated to certain provider groups. For example, Radiology Partners accounts for nearly all of radiology cases, while Team Health, SCP Health, and Envision represent well over half of all emergency cases.
Neurology and surgery, though a smaller volume (about 9 percent of resolved cases in 2024), won much higher awards than radiology or emergency services. In Q1 of 2024, the median prevailing party offer for neurology was 1222 percent of QPA, followed by 1178 percent in Q2. The median prevailing party offer for surgery was 1818 percent of QPA in Q1 and 1716 percent of QPA in Q2.
Plan Offers Minimally Increase; Win Rates Remain Low
Plan success in IDR is generally similar across 2023 and 2024. In 2023, the rate of plans prevailed declined from 28 percent of resolved cases in Q1 to 15 percent in Q4. Results from 2024 are similar: plans won 14 percent of resolved cases in Q1 and 18 percent in Q2. As previously stated, in cases where plans prevailed, the median prevailing offer amount was 105 percent in both quarters of 2024—a small, but not insignificant, increase of 5 percent from 2023. This shift could indicate some effort by plans to respond to their history of losing IDR cases.
In Q1 and Q2 of 2024, the bulk of resolved IDR cases involved a few large plans as recipients of cases filed by providers. United Healthcare, Aetna, HCSC, and Anthem accounted for two thirds of cases. By one national measure, these four companies account for nearly half of the national insurer market.
Third party claims management companies account for at least a fifth of resolved cases. MultiPlan (now Claritev) and Clear Health Strategies are the two largest entities (13 percent and 7 percent, respectively). The increased volume of cases attributable to management companies could be evidence that plans, like providers, also leverage intermediaries to manage their disputes and maximize their OON claims revenue.
Significant Variation Among IDR Entity Volume and Decisions
The pace of IDR entity decision-making has substantially accelerated in 2024, yielding hope that case backlogs will be reduced. But our conversations with stakeholders have indicated another potential concern: that some IDR entities may decide in favor of providers significantly more than others. This concern is supported by our analysis of PUF data. We find that four IDR entities made decisions favoring providers in over 90 percent of their cases in 2024, while one entity favored providers in only one-third of its cases. Ideally, the overall decision-making pattern should be similar across all IDREs, so it will be important to understand why variations exist.
Litigation And The IDR Process
Litigation also continues to shape the implementation of the NSA. Several ongoing cases and appeals could have a significant impact on the success of the arbitration process and its role in affecting health care costs more broadly.
Providers, led by the Texas Medical Association, successfully leveraged litigation to block past efforts by the Biden Administration to put modest guardrails in place concerning how arbitration entities should consider and weigh the relevant statutory factors when deciding between two offers. But providers have not been successful in cases across the board. The Biden Administration won an appeal before a Fifth Circuit panel last fall in a further challenge brought by the Texas Medical Association and air ambulance providers (sometimes referred to as “TMA III”) concerning certain regulatory provisions outlining the calculation of the QPA. That decision overturned much (though not all) of the lower court’s decision siding with the providers. But legal fights over the QPA methodology have still not concluded. The providers asked the full Fifth Circuit to reverse the panel—and on May 30, 2025, the 5th Circuit issued an order vacating the previous opinion and directing that the case be reheard en banc (by all active judges on the court). Briefing will run through early September 2025 (with oral argument to be scheduled subsequently). While certain enforcement discretion related to the QPA remains in effect until August 1, 2025, future agency guidance may be needed to clarify the immediate impact of this development on patients and the arbitration process.
In another case on pause in federal district court in Kentucky, providers challenged several NSA regulatory provisions under the Administrative Procedure Act and the Takings Clause of the Fifth Amendment. Various other ongoing cases relate to efforts to overturn certain arbitration awards or compel payment by a party to arbitration. Some involve cases brought by providers against insurers and arbitration entities directly. The results in such cases have been mixed thus far, with appeals filed in the Fifth and Eleventh Circuits. The Department of Justice (DOJ), through amicus briefs, has urged courts to find that arbitration entities themselves are not proper parties to such cases—arguing that such litigation ultimately could result in “thwarting Congress’s desire to create a low-cost, efficient” arbitration process. As to alleged nonpayment by parties to the arbitration process once IDR payment determinations have been made, DOJ has also told courts that if parties cannot obtain relief in courts for such nonpayment, “one of the [NSA]’s core features would be frustrated, upending Congress’s scheme.”
Insurers have also filed multiple lawsuits alleging provider abuse of the IDR process through filing ineligible cases in order to obtain improper payment rates. Such cases remain in the early stages, but if they proceed, discovery could shed additional light on how certain providers are strategically leveraging the IDR process.
What Does It All Mean?
The analysis of resolved IDR cases shows that providers are often turning to IDR rather than accepting initial plan payments. Although the majority of cases are deemed eligible for the IDR process, plans are challenging the eligibility of nearly half the cases that providers file.
These high numbers highlight the disconnect between the two sides as they debate what constitutes a reasonable payment for OON services. Providers believe the high volume of IDR disputes reflects inadequate payment by plans, exacerbated by possible manipulation of the QPA. Plans respond that their QPAs are accurate and that providers should be willing to accept payments that align closely with in-network rates. Amidst this debate, the federal government has released the results of one QPA audit, and more audits could shed some light on the contrasting claims around QPAs.
Findings from the IDR data raise two important concerns. First, IDR cases are significantly concentrated among just a few provider organizations. Second, middlemen organizations are increasingly frequent users of the system. On one hand, middleman organizations could extend access to the IDR process to providers who are not part of large organizations and thus face administrative burdens in using the system. On the other hand, such organizations may contribute to higher overall case volume, increasing costs for the whole health system.
Additionally, providers continue to have a high share of cases decided in their favor, resulting in large payment awards. Providers make the case that their offers are simply more reasonable and that arbitrators agree. There are also some anecdotal reports that plans have been less aggressive than providers in putting their arguments in front of the IDR entities. As the federal agencies noted in background materials: “While health plans and issuers often benchmarked their offers to the QPA, providers, facilities, and air ambulance service providers often benchmarked their offers to past OON payment amounts with the disputing plan or issuers and past in-network rates with either the disputing plan or issuer, or with a different plan or issuer in the same state.” Plans have raised concerns that historical benchmarks may reflect circumstances before passage of the NSA when some plans paid full billed charges to ensure that costs were not passed along to consumers. Without public reporting of the rationale for IDR entity decisions, observers can only speculate how much historical payments influence the decisions.
The high volume of IDR cases, including the prevalence of ineligible cases, could be tempered if proposed rules for process improvements were finalized and if ongoing litigation over the QPA methodology was resolved. Better education, training, and oversight of IDR entity decision-making might also help reduce some of the uncertainties in the process.
The longer-term impact of IDR decisions on health costs is still mostly unknown. On the surface, it seems that the high provider winning rate and the size of the payments awarded would raise health costs and plan premiums. But the magnitude of any such increase is limited by the share of all health care claims represented by the IDR cases. Furthermore, stakeholder claims diverge wildly on whether we have seen an impact of the NSA on the size of provider networks or on negotiations over the fees paid to providers.
Notably, nothing in these findings from the IDR process raises questions about the effectiveness of the NSA in preventing consumers from experiencing surprise bills in the scenarios where the NSA created protections. The issue remains whether the law’s mechanism for establishing a reasonable payment from plans to providers is working. To the extent it is not, a key question is whether there are cost implications for the health care system as a whole and for consumers in particular.
To learn more about variation in the IDR process and potential cost implications, read the recently published companion piece: No Surprises Act Arbitrators Vary Significantly In Their Decision Making Patterns.
Jack Hoadley, Kennah Watts, and Zachary Baron “Independent Dispute Resolution Process 2024 Data: High Volume, More Provider Wins” June 11, 2025, https://www.healthaffairs.org/content/forefront/independent-dispute-resolution-process-2024-data-high-volume-more-provider-wins. Copyright © 2025 Health Affairs by Project HOPE – The People-to-People Health Foundation, Inc.
