Payers ranked by prior authorization denial rates

Health insurers denied between 12% and 18% of standard prior authorization requests across Medicare Advantage, Medicaid managed care and ACA marketplace plans in 2025, with wide variation among the largest payers, according to a KFF analysis published Aug. 13.

CMS previously finalized a rule requiring certain insurers to publicly report prior auth metrics, including denial rates, processing times and appeal overturn rates. The first reports, covering 2025, were due March 31. The data is aggregated across all items and services, with no breakdown by service type, so there’s limited insight into what services are being approved or denied. Payers are also not required to report reasons for denials.

The rankings below only cover standard prior auth requests and they don’t include data for prescription drugs (though CMS has proposed a rule to require that information to be public as well). Denial rates for urgent requests, which are included in KFF’s analysis, were slightly lower across all markets.

Prior auth denials are rarely appealed, but when they are, a considerable share are overturned, including 67% for Medicare Advantage plans, 47% in Medicaid managed care and 43% in the ACA marketplace.

Medicare Advantage prior authorization denial rates

1. UnitedHealth Group: 17%
2. Centene: 15%
3. Kaiser Permanente: 13%
4. CVS: 8%
5. Humana: 7%
6. Elevance: 5%

Medicaid prior authorization denial rates

1. Independence Health Group: 23%
2. CareSource: 20%
3. Centene: 18%
4. CVS: 17%
5. Molina: 11%
6. UnitedHealth Group: 11%
7. Elevance: 9%
8. L.A. Care Health Plan: 2%

ACA marketplace prior authorization denial rates

1. Centene: 25%
2. UnitedHealth Group: 21%
3. BCBS North Carolina: 18%
4. Oscar: 18%
5. Molina: 13%
6. Elevance: 10%
7. Health Care Service Corp.: 6%
8. GuideWell: 3%

Medicare Advantage prior authorization denials overturned on appeal

1. Centene: 93%
2. CVS: 89%
3. Elevance: 75%
4. Humana: 64%
5. UnitedHealth Group: 60%
6. Kaiser Permanente: 40%

Medicaid prior authorization denials overturned on appeal

1. UnitedHealth Group: 81%
2. Molina: 48%
3. Centene: 47%
4. Elevance: 36%
5. Independence Health Group: 36%
6. CareSource: 29%
7. CVS: 22%

ACA marketplace prior authorization denials overturned on appeal

1. Centene: 54%
2. Molina: 50%
3. BCBS North Carolina: 47%
4. Oscar: 43%
5. UnitedHealth Group: 38%
6. Elevance: 36%
7. GuideWell: 30%
8. Health Care Service Corp.: 16%

At the Becker's 11th Annual IT + Revenue Cycle Conference: The Future of AI & Digital Health, taking place September 14–17 in Chicago, healthcare executives and digital leaders from across the country will come together to explore how AI, interoperability, cybersecurity, and revenue cycle innovation are transforming care delivery, strengthening financial performance, and driving the next era of digital health. Apply for complimentary registration now.