For decades, the practice of "prior authorization"—the requirement that healthcare providers obtain approval from an insurer before performing a procedure, prescribing a medication, or ordering a test—has been a source of significant friction in the American healthcare system. While insurers maintain that the process is a vital tool for cost containment and the prevention of low-value care, patient advocates and clinicians have long argued that it serves as a bureaucratic barrier that delays essential treatment and increases administrative burnout.
According to KFF polling, nearly 7 in 10 insured adults view prior authorization as a significant burden. Recognizing this systemic tension, the Centers for Medicare and Medicaid Services (CMS) introduced a landmark regulation in 2024 aimed at shedding light on these opaque practices. For the first time, major insurers were required to publicly disclose standardized metrics regarding their authorization decisions. This analysis explores the landscape of these new data, the variations among industry giants, and what these numbers reveal about the state of American healthcare.
The 2024 Regulatory Shift: A New Mandate for Accountability
The 2024 CMS regulation represents a pivotal change in the oversight of Medicare Advantage, Medicaid managed care, and the Affordable Care Act (ACA) Marketplace. The core objective is twofold: to foster institutional accountability and to empower consumers with data as they shop for insurance coverage.
Under the new rules, insurers are required to publicly post aggregated prior authorization metrics—including approval rates, denial rates, and average response times—for all non-prescription medical items and services. These reports cover the previous calendar year, with the first major disclosure deadline falling on March 31, 2026, for the 2025 performance year.
Defining the Process
The regulation distinguishes between two primary types of requests:
- Standard Requests: Non-urgent, routine medical requests. For 2025, insurers were mandated to provide determinations within 14 days for Medicare Advantage and Medicaid, and 15 days for the ACA Marketplace.
- Expedited Requests: Urgent matters where a delay could jeopardize the patient’s life, health, or ability to regain function. All covered insurers were required to process these requests within 72 hours.
Chronology: From Policy to Performance
The journey toward this level of transparency began with mounting public pressure and a series of investigations by the HHS Office of Inspector General (OIG), which frequently highlighted how automated and often flawed denial processes were negatively impacting beneficiaries.
- February 2024: CMS publishes the final rule, setting the stage for nationwide standardized reporting.
- January–December 2025: The first performance year for which insurers were required to track and aggregate the new metrics.
- March 31, 2026: The inaugural deadline for insurers to publish their 2025 data on their public-facing websites.
- June 2025 – Present: Concurrent with the reporting, major industry players have launched voluntary initiatives, such as "gold carding" programs, to preempt stricter federal regulations by exempting high-performing providers from authorization requirements.
Supporting Data: What the 2025 Metrics Reveal
KFF’s analysis of 14 of the nation’s largest insurers—covering 25 million Medicare Advantage enrollees, 35 million Medicaid managed care enrollees, and 11 million ACA Marketplace participants—paints a complex picture of a fragmented system.
Approval and Denial Rates
The data indicate that while the majority of requests are approved, denial rates are not insignificant. Across the board, insurers denied between 12% and 18% of standard requests.
- Medicare Advantage: 12% of standard requests were denied.
- Medicaid Managed Care: 14% of standard requests were denied.
- ACA Marketplace: 18% of standard requests were denied.
Perhaps more striking than the averages is the wide variance between individual insurers. For instance, in the Medicare Advantage market, denial rates for standard requests spanned from as low as 5% at Elevance to as high as 17% at UnitedHealth Group. This discrepancy suggests that a patient’s experience with prior authorization is highly dependent on which insurer they choose, rather than the clinical necessity of the requested care.
The Appeals Process: A "Second Chance" for Patients
Perhaps the most telling metric is the "overturn rate" upon appeal. When patients or providers fight a denial, a significant portion are reversed, suggesting that the initial automated denial processes may be overly aggressive or lack sufficient clinical context.
- In Medicare Advantage, 67% of appealed denials were overturned.
- In Medicaid, 47% were overturned.
- In the ACA Marketplace, 43% were overturned.
The high overturn rate in Medicare Advantage—often exceeding 90% for certain insurers like Centene—raises urgent questions about the accuracy of initial utilization reviews and the administrative burden placed on providers who must navigate a lengthy, redundant appeals process to secure care that should have been authorized initially.
Median Response Times
On the surface, the data suggest efficiency. Median response times for standard requests hovered around one day across all markets. However, critics argue that "median" figures mask the outliers. While the average request might be processed quickly, a significant minority of patients—often those with the most complex, high-cost needs—experience delays that stretch far beyond the median, sometimes leading to severe clinical consequences.
Official Responses and Policy Implications
The insurance industry, through trade groups like AHIP, has generally framed these reporting requirements as a positive step toward modernization, emphasizing their commitment to real-time, automated electronic prior authorization. However, industry leaders are also cautious, arguing that publicly reported "denial rates" can be misleading if not contextualized by the "service mix"—the types of procedures that are subject to review.
The Transparency Gap
The current reporting framework faces several hurdles:
- Lack of Denominator Context: Insurers are not currently required to disclose the total number of requests, only percentages. This makes it impossible to tell if a low denial rate is a result of a lenient policy or a very small volume of requests.
- Inconsistent Reporting Standards: While CMS provided a template, it was not mandatory. Consequently, some insurers reported in hours, others in days, and some aggregated data nationally while others broke it down by state, making direct comparison a data-science challenge rather than a consumer-friendly process.
- The "Gold Card" Complication: Programs that exempt providers with high approval rates from future authorizations distort the data. If an insurer exempts their "best" providers, the remaining data only reflects the performance of providers who may struggle with administrative requirements, potentially skewing denial statistics.
Looking Forward: The Path to Meaningful Reform
The 2024 regulation is clearly just the beginning. In response to the identified gaps, CMS has already released updated guidance for 2027 that mandates clearer reporting of numerators and denominators.
Furthermore, the "2026 Proposed Rule" suggests a significant tightening of these requirements. If adopted, it would:
- Require numeric counts, not just percentages, for all metrics.
- Standardize the "denominators" to ensure apples-to-apples comparisons.
- Extend reporting requirements to include prescription drugs, a massive area of the healthcare economy previously excluded from these metrics.
Legislative Efforts
Beyond administrative rules, Congress is eyeing the Improving Seniors’ Timely Access to Care Act of 2025. This bill aims to go further by requiring the public disclosure of how often artificial intelligence and algorithmic tools are used to facilitate denials. As state-level experiments—such as those in Massachusetts and Iowa—begin to restrict prior authorization for routine services, the federal government is under increasing pressure to synchronize these efforts into a cohesive national strategy.
Ultimately, the data from 2025 has confirmed what many patients and doctors already knew: the prior authorization system is vast, highly variable, and prone to error. While the current transparency mandates are an essential first step, the next phase of policy must focus on moving beyond simply counting denials and toward ensuring that the process does not impede the fundamental delivery of necessary medical care. For the American healthcare system, the era of "black box" denials is slowly coming to an end, replaced by a new, albeit messy, reality of data-driven accountability.
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