Denial and Appeal Benchmark 2026
How often U.S. health insurers deny claims, how often appeals succeed, and how rarely anyone appeals, from the three public records that exist: what issuers report to CMS, what independent reviewers decided in California, and what state regulators publish. Every number carries its N and its source. Nothing here is estimated.
Key findings
1. Denials and internal appeals reported to CMS, by year
HealthCare.gov medical issuers, issuer level. Medians are across issuers with at least 1,000 in-network claims. The file for a plan year reports claims from two years earlier.
| File | Issuer filings | In-network claims | Denied | Pooled denial rate | Median issuer rate | Internal appeals | Overturned | Median ext. review overturn |
|---|---|---|---|---|---|---|---|---|
| PY2024 file (2022 claims) | 210 | 358,926,163 | 57,593,247 | 16.0% | 15.5% | 110,274 | 43.0% | 64.1% |
| PY2025 file (2023 claims) | 207 | 436,012,342 | 85,897,790 | 19.7% | 18.3% | 376,704 | 43.8% | 0.0% |
| PY2026 file (2024 claims) | 186 | 451,278,469 | 84,505,304 | 18.7% | 19.0% | 263,181 | 32.6% | 0.0% |
Source: CMS Transparency in Coverage Public Use File (Health Insurance Exchange PUFs), plan years 2024, 2025, 2026; Apellica tabulation, methodology. Download: CSV.
2. States, by median issuer denial rate (2024 claims)
Only the 32 states that use HealthCare.gov are in the CMS file. State-based marketplaces (California, New York and others) do not report here.
| State | Issuers | Median issuer denial rate | Pooled denial rate | In-network claims | Internal appeals overturned |
|---|---|---|---|---|---|
| Delaware | 3 | 28.0% | 19.7% | 2,232,506 | 32.4% |
| Oklahoma | 7 | 22.9% | 18.3% | 11,625,740 | 28.0% |
| Alaska | 2 | 22.2% | 25.3% | 946,098 | 47.7% |
| West Virginia | 2 | 21.8% | 21.0% | 3,184,929 | 9.4% |
| Texas | 18 | 21.6% | 18.5% | 120,606,438 | 36.9% |
| North Carolina | 7 | 21.5% | 19.9% | 23,717,695 | 27.2% |
| Nebraska | 5 | 21.3% | 19.6% | 1,959,261 | 39.0% |
| Iowa | 6 | 21.3% | 18.8% | 4,833,668 | 30.5% |
| Arizona | 7 | 21.2% | 20.1% | 7,874,919 | 30.4% |
| Mississippi | 5 | 21.1% | 18.3% | 14,872,712 | 14.2% |
| Tennessee | 6 | 20.7% | 20.1% | 22,656,628 | 31.9% |
| Florida | 16 | 20.2% | 22.2% | 82,397,280 | 36.7% |
| South Carolina | 6 | 20.1% | 17.0% | 21,454,469 | 31.6% |
| Ohio | 11 | 20.0% | 17.9% | 16,409,625 | 28.4% |
| Michigan | 8 | 19.9% | 17.4% | 13,652,457 | 24.7% |
| Missouri | 8 | 19.9% | 15.6% | 12,197,986 | 32.8% |
| Kansas | 6 | 19.7% | 18.2% | 6,298,697 | 29.4% |
| Alabama | 4 | 19.0% | 18.9% | 18,358,599 | 44.0% |
| Utah | 6 | 18.7% | 18.6% | 9,574,696 | 26.9% |
| Louisiana | 6 | 18.1% | 18.6% | 9,356,149 | 33.9% |
| Indiana | 5 | 18.1% | 15.2% | 6,461,283 | 19.3% |
| Wyoming | 2 | 17.6% | 17.6% | 1,305,051 | 39.9% |
| Hawaii | 2 | 16.2% | 27.0% | 735,147 | 49.6% |
| Arkansas | 6 | 15.8% | 15.9% | 17,922,408 | 24.7% |
| North Dakota | 3 | 13.5% | 9.8% | 1,432,238 | 52.2% |
| New Hampshire | 5 | 13.3% | 10.4% | 3,105,818 | 42.2% |
| Montana | 3 | 11.5% | 11.6% | 2,012,780 | 24.9% |
| Wisconsin | 12 | 10.8% | 12.1% | 9,824,576 | 49.9% |
| Oregon | 6 | 10.2% | 10.9% | 2,552,164 | 31.7% |
| South Dakota | 3 | 4.1% | 6.5% | 1,716,452 | 49.2% |
3. Issuers at the ends of the range (2024 claims)
Sorted by reported in-network denial rate among the 158 issuer filings with at least 1,000 claims. Issuer names as CMS prints them. A high rate is not evidence of intent; the file counts every denial reason, including duplicates.
| Highest reported rates | Rate | Claims |
|---|---|---|
| Imperial Insurance Companies, Inc. (TX) | 35.6% | 2,530 |
| Imperial Insurance Companies, Inc. (AZ) | 33.1% | 2,393 |
| Select Health of South Carolina (SC) | 32.6% | 121,039 |
| Community First Insurance Plans (TX) | 30.6% | 112,382 |
| Harvard Pilgrim Health Care of NE (NH) | 28.8% | 117,211 |
| CareSource North Carolina Co. (NC) | 28.3% | 158,212 |
| Celtic Insurance Company (DE) | 28.2% | 24,728 |
| AmeriHealth Caritas North Carolina, Inc. (NC) | 28.2% | 387,771 |
| Oscar Health Plan, Inc. (AZ) | 28.1% | 292,877 |
| AmeriHealth Caritas VIP Next, Inc. (DE) | 28.0% | 165,638 |
| Lowest reported rates | Rate | Claims |
|---|---|---|
| Avera Health Plans, Inc. (SD) | 2.7% | 436,009 |
| Providence Health Plan (OR) | 4.0% | 410,010 |
| Sanford Health Plan (SD) | 4.1% | 855,229 |
| Sanford Health Plan (ND) | 4.4% | 642,746 |
| Kaiser Foundation Health Plan, Inc. (HI) | 5.1% | 11,489 |
| HealthPartners Insurance Company (WI) | 6.5% | 466,789 |
| Capital Health Plan (FL) | 6.5% | 540,104 |
| Matthew Thornton Hlth Plan(Anthem BCBS) (NH) | 7.0% | 2,199,992 |
| Kaiser Foundation Healthplan of the NW (OR) | 7.3% | 9,923 |
| Healthy Alliance Life Co(Anthem BCBS) (MO) | 7.5% | 3,941,746 |
4. What independent reviewers decided: California IMR, by treatment
Every Independent Medical Review decision published by the California Department of Managed Health Care, 2001 to 2026. A decision counts as overturned when the reviewer reversed the plan in whole or in part.
| Treatment category | Decisions | Overturned | Rate |
|---|---|---|---|
| Weight Control | 1,581 | 1,365 | 86.3% |
| RTC | 1,390 | 1,119 | 80.5% |
| Anti-virals | 1,351 | 1,100 | 81.4% |
| MRI | 1,068 | 457 | 42.8% |
| RTC/ Admit | 1,061 | 440 | 41.5% |
| Lab Work | 1,015 | 321 | 31.6% |
| Speech Therapy | 972 | 718 | 73.9% |
| Hormones | 971 | 418 | 43.0% |
| Viscosupp Injection | 844 | 792 | 93.8% |
| Mammography | 784 | 731 | 93.2% |
| Genetic/Genomic Test | 582 | 301 | 51.7% |
| Biologics | 527 | 412 | 78.2% |
Source: California Department of Managed Health Care, Independent Medical Review (IMR) Determinations, Trend (CHHS Open Data); Apellica tabulation, methodology. Download: CSV.
5. The appeal gap
KFF's analysis of the 2024 HealthCare.gov filings counted about 451 million in-network claims, about 85 million denied (19%), and at least 262,982 appeals: an appeal rate below 1%. Insurers upheld 66% of those appeals and reversed 34%. Apellica's tabulation of the same file, above, gives 18.7% denied and 32.6% of appeals overturned; the small differences come from which issuer rows are pooled. Independent review, where the decision leaves the insurer's hands, reverses the plan far more often: 52.5% of California IMR decisions and 47.9% of the external reviews state regulators report.
Read together, the three records say the same thing: a denial is a first answer that is rarely tested, and when it is tested by an independent reviewer it fails about half the time. The person who gives up is the insurer's most reliable outcome.
Methods and limits
- CMS figures are self-reported by issuers at the issuer-and-state level and cover HealthCare.gov plans only. "Denied" includes duplicate, administrative and eligibility denials. Stand-alone dental issuers are excluded. Pooled rates weight large issuers more; medians treat each issuer filing equally.
- California IMR decisions are the population of cases that reached independent review, not a sample of all denials. Overturn rates by treatment and diagnosis are reported with N; combinations with fewer than 5 decisions are not published.
- State external-review totals come from each regulator's annual report where one is published; states without published totals are shown as data gaps in the index, not estimated.
- Nothing on this page predicts an individual claim. It describes populations.
Cite or reuse
Free to cite and reuse with attribution, CC BY 4.0. Suggested citation:
Apellica (2026). Denial and Appeal Benchmark 2026. Tabulated from CMS Transparency in Coverage PUFs (PY2024 to PY2026), California DMHC IMR determinations, and state external-review reports. https://apellica.com/research/denial-appeal-benchmark-2026
Corrections and data questions: editorial@apellica.com. Press: press@apellica.com.
Sources
- CMS Transparency in Coverage Public Use File (Health Insurance Exchange PUFs) and data dictionary.
- California Department of Managed Health Care, Independent Medical Review (IMR) Determinations, Trend (CHHS Open Data).
- Apellica External Review Index, compiled from state regulators' annual reports.
- KFF, Claims Denials and Appeals in ACA Marketplace Plans in 2024 (24 March 2026).
General information, not legal or medical advice. Apellica is an appeal-preparation service, not a law firm.