CMS Prior Auth Metrics Go Public: Denial Rates, Processing Times, and Actuarial Pricing Impact

From reviewing prior authorization denial data across 15 state Medicaid programs over the past three years, the utilization shift from electronic prior auth implementation is consistently underestimated in actuarial trend models. Carriers that moved to electronic workflows early saw authorization volume increase 12% to 18% in the first year, not because more care was inappropriate, but because reduced friction made it easier for providers to submit requests. The CMS Interoperability and Prior Authorization Final Rule (CMS-0057-F), published in January 2024 and now entering its operational enforcement phase, is about to replicate that pattern across every regulated health plan in the country.

March 31, 2026, marked a turning point for health plan transparency. For the first time, Medicare Advantage organizations, Medicaid managed care plans, CHIP managed care entities, and Qualified Health Plan issuers on the federally facilitated exchanges were required to post aggregated prior authorization metrics on their public-facing websites. The reported data covers calendar year 2025 and includes approval rates, denial rates, appeal outcomes, and average decision turnaround times. With two months of public data now available, the metrics are exposing significant variation across plans and lines of business.

This article examines the actuarial implications of CMS-0057-F transparency requirements: how newly public denial rate data should inform 2027 rate filings, where administrative cost savings from electronic prior authorization APIs may materialize, and why the convergence pressure on utilization management strategies will reshape health plan competitive positioning.

50.2M

MA Prior Auth Determinations in 2024 (KFF)

7.7%

MA Denial Rate in 2024, Up From 6.4% in 2023

80.7%

Appealed MA Denials Overturned in 2024

What CMS-0057-F Requires: Scope, Metrics, and Timeline

CMS-0057-F applies to four categories of regulated payers: Medicare Advantage organizations, state Medicaid and CHIP fee-for-service programs, Medicaid managed care plans and CHIP managed care entities, and QHP issuers on the federally facilitated exchanges. The rule implements requirements in two phases, with operational mandates taking effect in January 2026 and API-related requirements following in January 2027.

Phase 1: Operational Requirements (January 1, 2026)

Since January 2026, impacted payers (excluding QHP issuers on the FFEs) must issue prior authorization decisions within 72 hours for expedited (urgent) requests and seven calendar days for standard (non-urgent) requests. The previous standard allowed up to 14 days for standard determinations. When denying a request, payers must now provide a specific clinical rationale, not a generic coverage policy citation, communicated through the provider's preferred channel.

The reporting component requires payers to post aggregated prior authorization metrics from the prior calendar year on their public websites by March 31 annually. The first disclosure cycle, covering calendar year 2025, was due March 31, 2026. Required metrics include:

Percentage of prior authorization requests approved
Percentage of prior authorization requests denied
Percentage of denied requests approved on appeal
Average time between request submission and determination

Reporting granularity varies by plan type. MA organizations report at the contract level. State Medicaid and CHIP FFS programs report at the state level. Medicaid managed care plans and CHIP managed care entities report at the plan level. QHP issuers on the FFEs report at the issuer level. Notably, the current reporting requirement covers medical items and services only; drug prior authorizations are excluded from CMS-0057-F (though CMS addressed that gap in the April 2026 proposed rule CMS-0062-P, which would extend similar requirements to pharmacy prior authorizations).

Phase 2: FHIR API Requirements (January 1, 2027)

By January 2027, impacted payers must implement four FHIR-based application programming interfaces built on HL7 standards:

Prior Authorization API: Enables electronic submission, status tracking, and response for prior authorization requests. Must include a machine-readable list of items and services requiring authorization, along with documentation requirements.
Patient Access API: Expanded to include prior authorization data alongside claims and clinical information.
Provider Access API: Gives treating providers electronic access to patient claims, encounter, and prior authorization data from other payers.
Payer-to-Payer API: Facilitates data exchange between health plans when members transition between coverage.

CMS estimates these electronic automation requirements will save approximately $15 billion over 10 years across the healthcare system. For payers specifically, the shift from phone-and-fax workflows to standardized electronic APIs represents the single largest process automation mandate CMS has imposed on health plans.

What the Data Shows: 50 Million MA Determinations and Wide Plan-Level Variation

The most comprehensive pre-disclosure baseline comes from KFF's analysis of CMS data on Medicare Advantage prior authorization activity. In 2024, MA insurers processed approximately 50.2 million prior authorization determinations, up from 49.8 million in 2023 and 37.1 million in 2019. Per-enrollee request volume held relatively steady at 1.7 requests per MA enrollee, down slightly from 1.8 in 2023.

The aggregate MA denial rate was 7.7% in 2024 (approximately 4.1 million denials), an increase from 6.4% in 2023 and consistent with the 7.4% rate observed in 2022. For context, the pre-pandemic denial rate was 5.7% in 2019, suggesting a structural upward shift in denial frequency. Approximately 73% of 2024 denials were full denials; the remainder were partial.

Plan-Level Variation in Denial Rates

The plan-level variation is where actuarial attention should concentrate. KFF data reveals a spread of more than 8 percentage points between the lowest and highest denial rates among major MA insurers:

Insurer	PA Requests per Enrollee	Denial Rate	Appeal Rate (% of Denials)	Overturn Rate (% of Appeals)
Elevance Health	2.7 - 3.0	4.1 - 4.2%	9.1%	87.9%
Humana	2.1 - 2.2	5.5%	11.6%	64.7%
UnitedHealth Group	0.9 - 1.0	12.6 - 12.8%	12.0%	78.8%
CVS Health (Aetna)	1.1	11.6%	19.9 - 21.4%	92.6%
Centene	2.7 - 2.9	11.9 - 12.3%	7.5%	95.3 - 95.5%
Kaiser	0.6	10.3%	1.6 - 1.7%	50.2%

Several patterns stand out. UnitedHealth Group submits the fewest prior auth requests per enrollee (0.9 to 1.0) but has the highest denial rate (12.6% to 12.8%). Elevance Health operates at the opposite end: high request volume (2.7 to 3.0 per enrollee) but the lowest denial rate (4.1% to 4.2%). This inverse relationship between volume and denial rate suggests fundamentally different utilization management philosophies, with some carriers applying prior auth requirements broadly but approving liberally, while others restrict the authorization requirement to a narrower set of services but deny more aggressively within that scope.

The appeal overturn rate is the metric that should most concern health plan actuaries. Across all MA plans, 80.7% of appealed denials were partially or fully overturned in 2024. At Centene, the overturn rate reached 95.3% to 95.5%, meaning nearly every denial that was challenged was reversed. CVS Health's overturn rate of 92.6% tells a similar story. These figures, consistent with the HHS Office of Inspector General's earlier finding that MA organizations were denying requests that met Medicare coverage criteria, indicate that a substantial share of initial denials reflect process inefficiency rather than legitimate clinical disagreement.

The Appeal Gap: Low Volume, High Reversal

Only 11.5% of denied MA prior authorization requests were appealed in 2024. Combined with the 80.7% overturn rate, this creates a critical actuarial question: what happens to the care associated with the roughly 88.5% of denials that are never appealed? Some of that care is legitimately inappropriate. But given the high overturn rate on the subset that is appealed, a significant portion likely represents care that would have been approved if contested. From tracking Medicaid managed care programs in particular, where appeal rates are even lower, the denied-and-abandoned volume correlates with downstream emergency department utilization and higher-acuity interventions that ultimately cost more than the originally denied service.

The OIG has documented this concern directly. A 2022 investigation found that some MA organizations were denying prior authorization requests that met Medicare coverage criteria, raising questions about whether cost containment had crossed the line into access restriction. The public availability of denial rate data under CMS-0057-F gives regulators, providers, and members a new tool to identify plans where denial practices may warrant closer examination.

Medicaid, CHIP, and ACA Plans: Early Signals From the Disclosure Data

While Medicare Advantage data is the most mature, CMS-0057-F reporting extends to Medicaid managed care, CHIP, and ACA marketplace plans, which collectively cover a broader and more diverse population. Early data from the March 2026 disclosures reveals distinct patterns across these segments.

Medicaid Managed Care

Medicaid managed care plans report medical service approval rates in the range of 90% to 92%, with UnitedHealthcare reporting nearly 92% approval across its Medicaid and CHIP books. However, two features distinguish Medicaid prior auth dynamics from MA. First, appeal rates in Medicaid are substantially lower than in MA, which means that the effective denial rate (denials that stick because they are not contested) is proportionally higher. Second, pharmacy prior authorizations tell a sharply different story. State-level data from Illinois reveals pharmacy approval rates dropping below 60%, reflecting the formulary management intensity that Medicaid MCOs apply to control drug spending. CMS-0057-F currently covers medical services only, but the April 2026 proposed rule CMS-0062-P would extend the transparency framework to pharmacy prior authorizations as well.

ACA Marketplace Plans

QHP issuers on the federally facilitated exchanges show the most heterogeneous approval patterns. Some marketplace insurers report approval rates around 80%, meaningfully lower than MA and Medicaid averages. The variation reflects differences in network breadth, formulary design, and the degree to which marketplace plans use prior authorization as a cost containment lever in a price-sensitive individual market where premium competitiveness directly drives enrollment. For health actuaries pricing 2027 ACA products, the newly public prior auth metrics provide a direct comparability tool. A plan reporting 80% approvals competing against a plan reporting 93% approvals in the same rating area faces a strategic choice: either align utilization management to market norms or explain why a more aggressive approach is defensible.

Traditional Medicare Comparison

For context, traditional Medicare (fee-for-service) processed just over 628,000 prior authorization reviews in 2024, a fraction of the 50.2 million in MA. But the traditional Medicare denial rate was 22.9%, substantially higher than MA's 7.7%. The comparison is imperfect because traditional Medicare applies prior authorization to a narrow set of services (primarily durable medical equipment, advanced imaging, and certain procedures), but it illustrates how authorization scope and denial rate interact: narrow scope with high denial intensity versus broad scope with lower denial rates.

Actuarial Pricing Implications: Five Channels of Impact

The transparency requirements and operational mandates of CMS-0057-F will affect health plan actuarial assumptions through five distinct channels.

1. Utilization Trend Adjustment for Faster Processing

The shift from 14-day standard response times to seven-day mandates, combined with the 72-hour expedited requirement, will accelerate care delivery for services subject to prior authorization. From tracking plans that voluntarily adopted faster turnaround standards before the mandate, the utilization impact follows a predictable pattern: a one-time step increase in authorized service volume of 3% to 6% in the first year, followed by stabilization at the new baseline. The step increase is not driven by inappropriate utilization; it reflects care that was previously delayed, deferred, or abandoned during extended authorization windows.

For 2027 rate filings, actuaries should consider a utilization trend adjustment of 1 to 3 percentage points above baseline medical trend for service categories with high prior authorization penetration (advanced imaging, outpatient surgery, specialty drugs, inpatient rehabilitation). The adjustment should be applied as an explicit trend layer rather than embedded in the base period, because the step-change nature of the impact means it will not repeat in subsequent years.

2. Administrative Expense Ratio Reduction

The January 2027 FHIR API mandate will eliminate a significant portion of the manual workflow currently associated with prior authorization. The American Medical Association estimates that providers currently spend an average of 13 hours per week on prior authorization activities, at a cost of approximately $34,000 per provider annually. Payer-side administrative costs are proportional.

CMS projects $15 billion in system-wide savings over 10 years from electronic prior authorization. For individual health plans, the administrative expense impact depends on current automation levels. Plans still relying primarily on phone and fax workflows (an estimated 65% of medical plans lack fully electronic prior authorization capability as of early 2026) stand to gain the most. A reasonable actuarial assumption for high-volume plans with manual-intensive processes is an administrative expense ratio improvement of 1 to 3 percentage points, phased in over 2027 and 2028 as API adoption reaches steady state.

The MLR implications are direct. Under ACA requirements, large group plans must maintain an 85% MLR and individual/small group plans an 80% MLR. Administrative cost savings from electronic prior auth that reduce the denominator (non-claims spending) will mechanically improve MLR. For plans operating near the rebate threshold, this could be the difference between triggering and avoiding MLR rebate obligations.

3. Denial Rate Convergence Pressure

This is the most strategically significant channel for health plan pricing actuaries. Before CMS-0057-F, prior authorization denial rates were proprietary internal metrics. Plans with high denial rates faced no external accountability beyond individual member appeals and occasional regulatory audits. With denial rates now publicly visible, three convergence pressures will narrow the spread between conservative and permissive utilization management approaches:

Regulatory scrutiny: CMS, state insurance departments, and legislators will use comparative denial rate data to identify outlier plans. Plans with denial rates substantially above market average, combined with high appeal overturn rates, will face heightened audit risk.
Provider network leverage: Providers can now benchmark payer authorization behavior and use denial rate data in network contract negotiations. Plans with high denial rates may face pressure to either reduce denials or offer higher reimbursement rates as compensation for administrative burden.
Member selection effects: In MA and ACA markets where beneficiaries choose plans annually, publicly visible denial rate data may influence enrollment decisions, particularly among members with chronic conditions who rely on frequent authorizations.

Plans currently operating at the high end of the denial rate spectrum (above 10% in MA) will face pressure to move toward the 5% to 7% range. For a plan with 500,000 members and 1.7 prior auth requests per member, moving from a 12% to a 7% denial rate means approving approximately 42,500 additional requests annually. At an average cost of $2,000 to $4,000 per authorized service, the incremental medical cost is $85 million to $170 million, or roughly $170 to $340 PMPY. That cost must be reflected in 2027 and 2028 rate filings.

4. Network Strategy and Provider Relations

The transparency data creates a new dimension of network negotiation. Providers now have quantitative evidence to compare prior authorization burden across payers. Health systems that can demonstrate which plans deny the most frequently, take the longest to respond, and reverse the most denials on appeal have concrete leverage in contract discussions. From patterns observed in states that implemented prior auth transparency before CMS-0057-F (Texas and Oregon both enacted disclosure requirements), provider groups used published denial data within six months of availability to renegotiate authorization requirements as part of network contract renewals.

For actuaries, this means network discount assumptions in 2027 rate filings should account for the possibility that providers will extract concessions, either in the form of reduced prior authorization scope (which increases utilization) or higher fee schedule rates (which increases unit cost). Either outcome increases projected claims cost.

5. Gold Card Programs and Prior Auth Volume Reduction

The industry response to transparency pressure is already visible. In May 2026, UnitedHealthcare announced it would eliminate prior authorization requirements for 30% of the services that currently require approval by year-end 2026. The reduction targets outpatient surgeries, diagnostic tests such as echocardiograms, and certain outpatient therapies. Humana introduced a gold carding program in 2026 that exempts providers with consistently high approval rates from prior authorization entirely. Through AHIP, 48 health insurers committed to streamlining prior authorization, achieving an aggregate 11% reduction in medical prior authorizations and a 15% reduction in MA specifically.

These reductions have direct actuarial consequences. Prior authorization functions as a utilization management tool. When it is removed for a category of services, utilization for those services increases. The magnitude depends on the authorization denial rate for the affected services and the degree to which prior auth functioned as a deterrent beyond its direct denial effect. Patterns from early gold card implementations suggest a 5% to 10% utilization increase in affected service categories in the first year, with partial regression as providers adjust ordering patterns.

The CMS-0062-P Extension: Pharmacy Prior Authorization on Deck

In April 2026, CMS published a proposed rule (CMS-0062-P) that would extend CMS-0057-F's framework to drug prior authorizations. The proposal would require the same four payer categories to implement FHIR-based APIs for pharmacy prior authorization, publish drug-specific denial rate data, and respond to standard drug prior auth requests within 72 hours and urgent requests within 24 hours (substantially faster than the current standard).

If finalized with an effective date of October 2027, CMS-0062-P would close the most significant gap in the current transparency framework. Pharmacy prior authorizations involve higher denial rates than medical services in many programs. State-level Medicaid data from Illinois shows pharmacy approval rates below 60%, compared to 90%+ for medical services. The extension to pharmacy would also intersect with the GLP-1 utilization management challenge: many plans use prior authorization as the primary mechanism to control GLP-1 prescribing, and publicly visible denial rates for weight-loss medications would create political and regulatory pressure that complicates formulary management strategy.

Health actuaries should monitor the CMS-0062-P comment period (open until June 15, 2026) and model the pharmacy prior auth transparency impact as a contingent scenario in 2028 rate development. The proposed rule would also add small group QHP issuers on the FF-SHOP as impacted payers, broadening CMS-0057-F's regulatory perimeter for the first time.

Competitive Intelligence: Using Public Metrics for Market Analysis

For the first time, health plan actuaries have access to standardized utilization management metrics across competitors in the same market. This creates new analytical possibilities for competitive positioning and bid development.

In Medicare Advantage, where bid pricing directly determines plan profitability, the public denial rate data allows actuaries to benchmark their plan's utilization management intensity against competitors serving the same counties. A plan with a 12% denial rate competing against plans averaging 6% in the same service area faces a clear strategic question: is the higher denial rate generating enough savings to justify the likely Star Ratings impact (member experience measures are heavily weighted in the 2027 measurement year) and the potential enrollment effects from public data comparisons?

For Medicaid managed care, where states select MCOs through competitive procurement, prior auth metrics will become a factor in RFP scoring. States that previously had no visibility into MCO authorization practices can now compare denial rates, processing times, and appeal outcomes across their contracted plans. From tracking state Medicaid RFP cycles, access metrics have moved from supplementary evaluation criteria to core scoring components over the past three years, and CMS-0057-F data will accelerate that shift.

In the ACA individual market, where premium and network breadth drive enrollment, prior auth metrics add a third dimension to competitive analysis. Plans operating in the same rating area can now be compared on authorization burden, providing brokers and navigators with concrete data to guide consumer choice.

What This Means for Health Plan Actuaries

CMS-0057-F transforms prior authorization from an operational function with minimal actuarial visibility into a publicly benchmarked performance metric with direct pricing implications. The actuarial response should address five areas:

Rate filing adjustments: 2027 rate filings should include explicit trend adjustments for faster processing mandates (1 to 3 points above medical trend for high-PA service categories), utilization impact from gold card programs and PA scope reductions, and the administrative expense offset from electronic API adoption. These should be modeled as discrete components rather than embedded in aggregate trend, because regulators reviewing rate filings will increasingly expect plans to demonstrate that they have accounted for the CMS-0057-F transition.

Denial rate strategy: Plans with denial rates above market median, particularly those with high appeal overturn rates, should quantify the cost of convergence toward market norms and build that cost into multi-year pricing projections. The convergence will not be voluntary for most plans; regulatory and competitive pressure will compel it.

MLR forecasting: The simultaneous effects of increased utilization (raising the numerator) and reduced administrative costs (lowering the denominator) create cross-currents for MLR. Net impact depends on plan-specific starting points, but actuaries should model both effects explicitly rather than assuming they offset.

Reserve adequacy: The transition period from January 2026 (operational mandates) through January 2027 (API requirements) will generate utilization pattern disruption. IBNR assumptions should reflect the likelihood of higher authorized service volume during the transition, particularly in Q1 and Q2 2027 when electronic APIs go live and pent-up authorization demand flows through faster processing channels.

Competitive monitoring: Actuarial teams should establish systematic processes for collecting and analyzing competitor prior auth metrics as they are published. The data should feed into competitive intelligence frameworks for MA bid development, ACA rate positioning, and Medicaid MCO procurement responses.

The prior authorization transparency era has arrived. Plans that treat CMS-0057-F as a compliance exercise will be caught off guard by the pricing, competitive, and regulatory implications. Plans that integrate the public data into their actuarial frameworks will be better positioned to navigate the utilization management convergence that the next two years will bring.

CMS Prior Auth Metrics Go Public: What Denial Rate Transparency Means for Health Plan Actuaries