What is IMR?
Independent Medical Review (IMR)is California's binding external review for many health plan denials based on medical necessity, emergency care disputes, or experimental/investigational treatment (HSC §§ 1374.30–1374.35).
An outside physician or clinician—not employed by your plan—reviews your records and decides whether the plan must cover the service. IMR is usually free to the member.
IMR is generally not the first step. Start with California internal appeals & grievances. General background: Appeals roadmap.
DMHC vs CDI
California has two IMR programs—use the one that regulates your plan:
- DMHC — most Knox-Keene health care service plans (Kaiser, most HMOs, most Covered California QHPs). Help Center: 1-888-466-2219
- CDI — many traditional health insurance policies (CDI IMR program). Consumer line: 1-800-927-4357
If you file with the wrong agency, they will usually forward your case. When unsure, call DMHC first—most Californians with commercial coverage are on DMHC-regulated plans.
When you can use it
IMR commonly applies when a plan:
- Denies, modifies, or delays a service based on medical necessity
- Denies payment for emergency care claiming it was not an emergency
- Refuses experimental or investigational treatment for a serious condition
IMR is usually not for pure billing disputes, wrong codes, or simple eligibility paperwork—see Denial decoder (those may still qualify for a DMHC/CDI consumer complaint).
You can generally request IMR when:
- You finished the plan's grievance/appeal process and got an unfavorable written decision, or
- The plan did not resolve your grievance within 30 days, or
- You qualify to skip or shorten internal review (urgent health threat, experimental denial, etc.)
File within 6 monthsof the plan's written resolution (28 CCR § 1300.74.30; Ins. Code § 10169(k)).
How to request it (step by step)
- Complete the plan's grievance/appeal process unless an exception applies (urgent or experimental cases).
- Gather documents: denial letters, NAR, medical records, clinician support letter.
- File IMR with DMHC or CDI:
- DMHC (recommended online): Online IMR/Complaint form · printable forms: IMR/Complaint forms (PDF)
- CDI: follow instructions at insurance.ca.gov — IMR (generally after insurer appeal is upheld or silent for 30 days)
- DMHC assigns an IMRO (independent review organization). The plan sends records; you may submit additional evidence.
- Receive the decision. If IMR overturns the denial, the plan must generally provide the service promptly (HSC § 1374.33).
Mail/fax to DMHC Help Center: 980 9th Street, Suite 500, Sacramento, CA 95814 · Fax 916-255-5241 (dmhc.ca.gov — File a Complaint).
How long it takes
Timelines vary by urgency and whether all records are received. DMHC public guidance includes:
- Acknowledgment: often within about 7 days if your case qualifies for IMR
- Standard IMR: often up to about 30–45 days (HSC § 1374.33(c); DMHC consumer materials)
- Expedited IMR: often about 7 days (urgent) or 3 days in some Medi-Cal IMR rules when health is at serious risk
- Consumer complaints (non-IMR issues): often decided within about 30 days
When it does not apply
- Self-funded ERISA employer plans — federal process
- Medicare / Medicare Advantage — CMS appeals
- Fee-for-service Medi-Cal — different DHCS rules (not Knox-Keene MCP IMR)
- After a Medi-Cal fair hearing on the same issue — you generally cannot also get IMR on that denial
- Services your contract never covers (plan exclusions)
For ongoing regulator issues, see Regulator complaints.
Urgent cases
If your doctor certifies that waiting would seriously jeopardize life, health, or ability to regain maximum function, you may only need about 3 days of internal plan review before DMHC will accept an expedited IMR—or DMHC may waive internal review entirely in some cases (HSC § 1368(b)).
For denials based on experimental/investigational treatment, you may be able to request IMR immediately without waiting 30 days (DMHC — File a Complaint).
For urgent prior authorization, see California prior authorization law and expedited appeals.