California external review

Independent Medical Review (IMR)File within 180 daysFee: None — the plan pays the cost of the reviewExpedited: about 7 days (3 days for CDI-regulated policies)

California's Independent Medical Review is one of the strongest external review systems in the country. It's free, you don't need a lawyer, decisions bind your health plan — and by DMHC's own 2024 annual report, about 73% of IMR cases end with the enrollee getting the requested service, either because the reviewer overturns the denial or the plan reverses itself first.

Who to contact
CA Department of Managed Health Care (DMHC)
www.dmhc.ca.gov/FileaComplaint/IndependentMedicalReviewComplaintProcess.aspx
1-888-466-2219
Authority: Health & Safety Code § 1374.30 (DMHC); Insurance Code §§ 10169–10169.5 (CDI)

Deadlines and decision timelines

How to file, step by step

  1. File a grievance with your plan first. Then wait 30 days for its response. Skip the wait entirely if your health is under serious, imminent threat or the denial was experimental/investigational.
  2. Submit the IMR/Complaint form. One form doubles as the IMR application and a consumer complaint — DMHC routes it correctly. File online at dmhc.ca.gov, or by mail or fax. An Authorized Assistant Form lets someone help you.
  3. Attach your doctor's support. Medical records and a physician letter matter — the IMR physicians decide on the clinical record. For expedited review, include written documentation of urgency.
  4. Decision, then coverage within 5 business days. Most IMRs are decided within 30 days of complete documentation. If the denial is overturned, your plan must authorize the service within 5 business days.

Who can use it

What to know

What California’s published IMR record shows

California publishes every Independent Medical Review decision. Across 42,749 published decisions (2001–2026), 52.5% ended with the denial overturned or the plan reversing itself. Outcomes for your specific situation: by treatment · by condition.

Source: California DMHC Independent Medical Review outcomes (CHHS Open Data)

Denial data from plans operating in California

Prior-authorization metrics these insurers disclosed for California contracts under the federal CMS-0057-F transparency rule (CY2025, insurer-published). A high denial rate paired with a high appeal-overturn rate is the profile worth appealing. Full methodology: insurer denial rates.
InsurerContract / planLineRequestsDeniedAppeals overturned
CenteneCA-SHP
Health Net
Medicaid3,096,1682.45%39.72%
CenteneCA-CalViva
Health Net
Medicaid310,3196.34%48.28%
CenteneH3561
Health Net
Medicare Advantage290,2571.98%77.5%
CenteneH0562
Health Net
Medicare Advantage184,5411.94%77.17%
CenteneH5087
Wellcare
Medicare Advantage120,4252.8%62.79%
CenteneCA-ImperialValley
Health Net
Medicaid57,4067.57%48.05%
Elevance HealthH4704
Anthem
Medicare Advantage9.2%56%
Elevance HealthH8552
Anthem
Medicare Advantage5%84%
Elevance HealthCA-Medicaid
Anthem
Medicaid2.6%34.1%
Elevance HealthH4161
Anthem
Medicare Advantage2.2%85.7%
Molina HealthcareH5810Medicare Advantage2%81%
Molina HealthcareH3038Medicare Advantage2%52%
Molina HealthcareCA-MEDICAIDMedicaid2%43%
Elevance HealthH0544
Anthem
Medicare Advantage1.6%66.7%
Molina HealthcareH5649Medicare Advantage1%50%
Elevance HealthH4471
Anthem
Medicare Advantage0.9%94.1%

California external review FAQ

How often do California IMRs succeed?

Per DMHC's 2024 annual report, about 73% of IMR cases end with the enrollee getting the requested service — either the independent reviewer overturns the denial or the plan reverses itself once the IMR is filed. Our published-decision data across 42,000+ IMRs shows similar patterns by treatment and condition.

DMHC or CDI — where do I file?

Most Californians — HMO members and most Covered California enrollees — file with the Department of Managed Health Care. A smaller set of policies regulated by the California Department of Insurance file with CDI (1-800-927-4357). If you file with the wrong agency, they forward your application; don't let the split stop you.

How long do I have to file?

Six months from your plan upholding its denial. You must generally file a grievance with the plan first and give it 30 days — waived when your health is under imminent, serious threat or the denial was experimental/investigational.

What happens if the IMR overturns my denial?

The decision binds your plan: it must authorize the service within 5 business days. IMR decisions are adopted by the state — the plan cannot appeal.

Can I see how similar cases were decided?

Yes. California publishes every IMR decision since 2001, de-identified, on the CHHS Open Data Portal — our treatment and condition pages aggregate all 42,000+ of them so you can see overturn rates for your exact situation.

Primary sources

Not legal or medical advice. Coverage Rights is a self-help tool that helps you prepare your own appeal. For advice about your specific situation, talk to a licensed attorney or your doctor.

Internal appeal first, external review second. We’ll map your path.

Explain my denial