By Max Quan and Kennah Watts
In the five years since its implementation, the No Surprises Act (NSA) has successfully protected patients from certain unpredictable, surprise bills. The bipartisan law guarantees that patients will pay no more than standard in-network cost-sharing for covered out-of-network services, and establishes a federal arbitration system to determine reimbursement for these out-of-network providers.
Since 2023, the Centers for Medicare & Medicaid Services (CMS)––one of the agencies responsible for NSA enforcement and oversight––has released regular reports on NSA compliance and enforcement. In June, CMS published an updated report with complaint and enforcement data from the law’s implementation to late last year (January 1, 2022 to December 31, 2025). This report summarizes NSA complaints from consumers, providers, payers, and others—along with some complaints related to the Affordable Care Act and the Mental Health Parity and Addiction Equality Act.
The updated complaints report shows that the NSA continues to shield patients from surprise bills. Emerging empirical evidence reaffirms this finding and indicates that consumers’ out-of-pocket costs may be decreasing as well.
Background on the NSA
Prior to the NSA, if a patient unknowingly or unavoidably received care from an out-of-network provider or facility, their insurer could refuse to cover the full costs and the provider could instead charge the patient for the balance. This charge––known as a surprise bill or balance bill––intended to cover the difference between the provider’s billed amount and the amount a patient’s health plan paid. These balance bills commonly resulted in thousands of dollars in unexpected charges, tens of thousands of dollars for air ambulance services, and, in rare cases, could reach nearly hundreds of thousands of dollars.
To protect consumers from surprise bills, the NSA banned balance bills in three scenarios: (1) out-of-network emergency care at hospitals or independent freestanding emergency departments, (2) care provided by an out-of-network provider at certain in-network facilities, and (3) out-of-network air ambulance services. With patients removed from the payment equation, policymakers needed to devise a mechanism to determine fair payment for providers and payers without contracted rates. Congress ultimately enacted the federal independent dispute resolution (IDR) process, an arbitration system for providers and plans to enter when private negotiations failed. This process was intended to be anchored around a median in-network rate––the qualifying payment amount (QPA)––and was expected to contain spending and, eventually, premiums, as providers would be incentivized to move in-network. However, unanticipated trends in volume and awards, in addition to constant legal challenges, suggest that the IDR process may not have these anticipated outcomes.
Complaints data demonstrate the NSA is protecting consumers from surprise bills
CMS’ recent report shows that in the first four years of implementation, relatively few NSA complaints have been made1. From 2022 to the end of 2025, nearly 40,000 NSA-related complaints were submitted to CMS. Compared to insurer estimates that nearly one million NSA-covered claims are submitted each month––which would equate to approximately 36 million claims across the entire implementation period––this volume is proportionally quite low (less than 1 percent). This low complaint level, in addition to payers’ anecdotal reports of few complaints, suggests that the NSA has protected patients from many surprise balance bills.
Of the roughly 15,000 complaints closed, 77 percent were filed against providers, facilities, and air ambulances. Nearly two-thirds of the closed complaints against providers were for balance billing, primarily for non-emergency services at an in-network facility (42 percent) and for emergency services (20 percent). Importantly, the report notes that these violations led to more than $30 million in “monetary relief,” which suggests that when providers incorrectly balance billed patients, the patients were refunded.
Less than a quarter (22 percent) of all closed complaints (approximately 1,700 complaints) were directed toward insurers and non-federal government plans. The three primary reasons for these complaints were QPA non-compliance, late IDR payments, and failure to provide an initial payment or notice of denial of payment within 30 days of a service. Given these reasons, it is likely these complaints were primarily, if not exclusively, submitted by providers.
The smaller count of complaints against insurers may be skewed by the delegation of regulatory authority: CMS’ jurisdiction includes non-federal governmental plans, while the Department of Labor has jurisdiction over self-funded plans, and fully insured plans often fall under state jurisdiction. Importantly, these other regulatory bodies also receive NSA-related complaints, but this report does not include complaints referred to these agencies.
Emerging evidence indicates the NSA may be lowering out-of-pocket costs
The complaint data underscores the success of the NSA’s consumer protections, and qualitative research supports this claim. A report by Georgetown and the Urban Institute finds that after NSA implementation, providers “turned off” their balance billing systems and that patients were taken “out of the middle” of payment disputes.
Emerging evidence also indicates that these protections may be translating into lower out-of-pocket costs. A recent study found a 16.5 percent reduction in out-of-pocket spending for patients in states without prior balance billing protections. States with prior protections did not see as dramatic a reduction. In creating a federal floor, the NSA appears to have helped protect patients and lower out-of-pocket costs.
Recent litigation underscores the importance of the complaints system and the Department’s enforcement authority
Since the NSA’s enactment, numerous aspects of the law and the IDR process have been heavily litigated. In hundreds of lawsuits, various stakeholders have repeatedly sued each other: providers have sued the Departments, payers, and IDR entities, while payers have sued providers and IDR middlemen. Many of the lawsuits hinge on whether or not the NSA authorizes a private right of action. While providers argue a private right of action is needed to enforce IDR awards and require payment from payers, the courts have almost unanimously held that the NSA does not include a private right of action. Only one district court has held that a limited right exists, but the litigation remains ongoing. In the absence of a private right of action, the courts direct providers to complain to the Departments, as the agencies hold authority to enforce plan noncompliance with the law. Relative to the number of IDR disputes and estimates of preventable balance bills, providers have filed a low level of complaints to CMS against payers. This low volume raises questions about whether and how often providers experience issues of non-payment or whether they find this complaints system a helpful means of resolving their concerns.
Looking forward
The NSA is landmark legislation that has protected millions of patients from many egregious, unavoidable balance bills. Early evidence also suggests that patients’ out-of-pocket costs have declined. The primary objective of the law appears to have been accomplished: patients have largely been taken out of the middle of balance billing. Less clear is whether the NSA’s payment dispute structure will ultimately lead to lower costs, and for consumers, more affordable health care. Going forward, it will be important to monitor complaints to ensure the NSA works as intended, particularly for protected patients.
