Health insurance · CMS Transparency in Coverage
Health insurers ranked by claim denial rate
Which health insurers deny the most marketplace claims, measured directly from CMS Transparency-in-Coverage filings, not estimates.
- 122
- Insurers ranked
- 20%
- Avg claims denied
- 37%
- Highest denial
According to the U.S. Centers for Medicare & Medicaid Services Transparency in Coverage Public Use File (plan year 2026), PlainInsurer analyzed more than 10,000 marketplace claims per insurer across the United States to rank health carriers by claim-denial rate. See our methodology for the full computation.
The headline
Among 122 individual-market health insurers with reportable CMS filing volume, CareSource North Carolina Co. reports the highest claim-denial rate (37.0%), while Avera Health Plans, Inc. reports the lowest (3.5%) - a gap of 34 points.
- 37%
- highest (CareSource North Carolina Co.)
- 20%
- volume-weighted average
- 3%
- lowest (Avera Health Plans)
- 122
- insurers ranked
CMS Transparency in Coverage covers individual-market filings, not employer plans or every insurance product. A reported denial rate reflects plan design and risk pool; it is not by itself proof of unfair practice.
Highest claim-denial rates
Top 12 health insurers by share of marketplace claims denied (≥10,000 claims on file)
- CareSource North Carolina
CareSource North Carolina Co.: 37.0% denied (76,854 of 207,708 claims, 1 states)
37 % of claims denied
- Select Health of South Car
Select Health of South Carolina: 36.5% denied (51,650 of 141,484 claims, 1 states)
37 % of claims denied
- Oscar Buckeye State Insura
Oscar Buckeye State Insurance Corp.: 36.4% denied (694,493 of 1,910,531 claims, 1 states)
36 % of claims denied
- UnitedHealthcare Community
UnitedHealthcare Community Plan, Inc.: 35.6% denied (395,425 of 1,110,639 claims, 1 states)
36 % of claims denied
- Oscar Health Plan
Oscar Health Plan, Inc.: 34.6% denied (119,454 of 344,800 claims, 1 states)
35 % of claims denied
- UnitedHealthcare of Oklaho
UnitedHealthcare of Oklahoma, Inc.: 33.7% denied (127,738 of 378,926 claims, 1 states)
34 % of claims denied
- UnitedHealthcare of Ohio
UnitedHealthcare of Ohio, Inc.: 33.2% denied (409,921 of 1,235,593 claims, 1 states)
33 % of claims denied
- Community First Insurance
Community First Insurance Plans: 32.5% denied (38,695 of 119,190 claims, 1 states)
33 % of claims denied
- Oscar Health Plan of North
Oscar Health Plan of North Carolina, Inc: 31.2% denied (33,542 of 107,392 claims, 1 states)
31 % of claims denied
- AmeriHealth Caritas North
AmeriHealth Caritas North Carolina, Inc.: 30.6% denied (139,608 of 456,084 claims, 1 states)
31 % of claims denied
- AmeriHealth Caritas Florid
AmeriHealth Caritas Florida, Inc.: 30.5% denied (28,025 of 92,022 claims, 1 states)
31 % of claims denied
- CareSource West Virginia C
CareSource West Virginia Co.: 30.5% denied (292,979 of 962,053 claims, 1 states)
31 % of claims denied
What this shows These carriers deny the largest share of marketplace claims in the CMS data. Many are Medicaid managed-care organizations, whose product design routes more claims through prior authorization.
Volume vs. denial rate
Each bubble is an insurer, placed by how many marketplace claims it handles and what share it denies. The largest carriers in the top band deny the most claims at scale.
122 health insurers ranked by claim-denial rate (showing top 50)
Reuse the data behind this ranking
Download the state-level marketplace claim-denial extract used for these comparisons. It includes only states with at least 50,000 reported claims and does not represent employer plans or every insurance product.
CMS Transparency in Coverage marketplace-claim-denial extract, PY2026 is published under CC0 1.0. Preserve the source, vintage, and scope when you cite it.
What to do with this
A high denial rate is a reason to check a plan's appeal record before you enrol.
- Look up your prospective carrier's full profile and per-state denial rate. Browse insurers
- Denied a claim? Follow the internal and external appeal process. Appeal a denial
- Understand why denial rates vary so much between plans. Read the guide
Verify a plan's current standing with your state insurance department and review its Summary of Benefits and Coverage before any decision. Informational only, not insurance advice.
Source: CMS Transparency in Coverage PUF PY2026. Grades are peer-relative composites of complaint index, denial rate, and prior-authorization data, they do not reflect financial strength. Not affiliated with NAIC or CMS.