Health Insurance Denial Rates by Insurer (2026 Data)
Which insurance companies deny the most claims? 2026 data on denial rates across major US insurers from CMS Transparency in Coverage, state insurance regulators, and federal reports.
Health insurance denial rates vary dramatically across insurers, plan types, and states. This page compiles the best available data from federal and state sources.
Important data note: The most comprehensive denial rate data comes from ACA marketplace plans required to report to CMS under the Transparency in Coverage rule. Self-funded employer plans (which cover approximately 65% of employer-sponsored insured workers) are exempt from state oversight and have limited public reporting requirements, meaning the true scope of denials across all commercial insurance is likely undercounted.
Denial Rates by Major Insurer
The following data is drawn from CMS Transparency in Coverage reporting, KFF analysis, and state insurance department reports. Rates reflect in-network claims denial rates and vary by state, plan type, and year.
| Insurer | Approx. denial rate | Primary states | Key notes |
|---|---|---|---|
| Cigna | 22–32% | National | Among highest in CMS data; noted by Senate subcommittee for prior auth denial patterns |
| UnitedHealthcare | 19–27% | National | Large volume; significant variation by subsidiary |
| Anthem/BCBS (various) | 17–23% | 14+ states | High variation by state; GA, CO, IN among highest |
| Aetna (CVS Health) | 16–22% | National | Prior auth denial rates noted in CMS data |
| Humana | 14–20% | National/Medicare Advantage | Higher MA denial rates noted by OIG |
| Kaiser Permanente | 7–13% | CA, CO, WA, GA, HI, VA, OR | Lower due to integrated model; less external claim disputing |
| Molina Healthcare | 18–25% | Medicaid/ACA | Medicaid managed care denial rates often higher |
| Oscar Health | 15–19% | Regional | Smaller national footprint; tech-forward model |
| Centene/WellCare | 20–28% | Medicaid/ACA | Medicaid managed care; noted in OIG reports |
Note: These are approximate ranges from publicly available data. Actual rates vary by plan type, state, and year. See sources below.
Denial Rates by Category
Denial rates vary significantly by claim type:
| Claim type | Approximate denial rate |
|---|---|
| In-network medical services | 10–20% |
| Prior authorization requests | 5–15% |
| Mental health/behavioral health | 15–25% |
| Substance use disorder treatment | 18–28% |
| Out-of-network emergency care | 25–40% |
| Experimental/investigational | 30–50%+ |
| Specialty drugs (PA required) | 15–25% |
Appeal Success Rates
Filing an appeal dramatically changes outcomes:
| Stage | Success rate |
|---|---|
| Internal appeal — enrollee initiated | 39–59% (KFF data) |
| External independent review | 25–45% |
| No appeal filed | 0% |
The critical data point: Only 0.1% of denied claims are appealed, despite the high success rate. Most people simply accept denials.
Medicare Advantage Denial Rates
Medicare Advantage (MA) plans have drawn particular scrutiny from the HHS Office of Inspector General:
- OIG Report (2022): MA plans denied 13% of requests that met Medicare coverage criteria — meaning they should have been approved under traditional Medicare rules
- Senate Finance Committee (2022): Found patterns of inappropriate denials and delayed care, particularly for post-acute care (skilled nursing, home health)
- Top MA deniers by OIG analysis: UnitedHealthcare, Humana, CVS/Aetna, Centene/WellCare cited in Congressional reports
The MA denial issue is significant because 50%+ of Medicare beneficiaries are now enrolled in MA plans, and MA has different (often higher) prior authorization requirements than traditional Medicare.
ClaimBack generates a professional appeal letter in 3 minutes — citing real insurance regulations for your country. Get your free analysis →
State-by-State Denial Variation
Denial rates vary significantly by state, influenced by state insurance regulations and market concentration:
Higher denial rate states (per CMS and state data):
- Georgia — significant Anthem/BCBS market share; consistent top-tier denial rates
- Texas — multiple insurers report high denial rates; limited state regulatory intervention
- Florida — high MA enrollment with elevated denial patterns
- Mississippi — high denial rates in both commercial and Medicaid managed care
Lower denial rate states (stronger regulations or different market mix):
- California — state has strong independent medical review; consumer protection laws
- New York — robust state insurance regulations; shorter appeal timelines
- Massachusetts — strong healthcare consumer protections; lower baseline denial rates
- Washington — Kaiser Permanente and Regence have lower denial rates; state oversight
Why Denial Rates Matter for Your Appeal
Understanding your insurer's denial rate in context helps you:
Know your baseline: If your insurer denies 22% of claims but you're in the 22% — you are exactly the norm, not a rare outlier. Appeals work.
Cite the data: Mentioning that your insurer has above-average denial rates in appeal letters (citing CMS sources) can signal to reviewers that you know the landscape.
External review context: External reviewers often know that certain insurers have aggressive denial patterns and may apply more scrutiny to internal denial decisions.
Sources
- CMS Transparency in Coverage data (annual marketplace reporting)
- KFF: Health Insurance Marketplace Plan Denial Rates — annual analysis
- HHS OIG: "Some Medicare Advantage Organization Denials of Prior Authorization Requests Raise Concerns About Beneficiary Access to Medically Necessary Care" (2022)
- Senate Finance Committee Report on Medicare Advantage (2022)
- State insurance department annual filings (California DOI, New York DFS, Texas TDI)
Fight Your Denial
Regardless of which insurer denied you — denials are overturned in 40–60% of properly filed appeals.
Start your appeal at ClaimBack →
Related Reading:
How much did your insurer deny?
Enter your denied claim amount to see what you could recover.
Your insurer is counting on you giving up.
Most people do. Less than 1% of denied claimants ever appeal — even though the majority who do win. ClaimBack was built by people who were denied, who fought back, and who refused to accept "no" from an insurer.
We give you the same appeal arguments that attorneys use — in 3 minutes, for free. Your denial deadline is ticking. Don't let it expire.
Free analysis · No credit card · Takes 3 minutes
Related ClaimBack Guides