By state / California

California

Regulator

California Department of Managed Health Care (DMHC)

External review

State-run. Request it through the regulator after the plan's final internal denial; the federal floor is 4 months (45 CFR 147.136).

Published reversal rate

0.727% of reviews reversed the plan (2024) · source

Notes

Headline: ~73% of IMR cases end with enrollee receiving requested service (full+partial overturn by IMRO + plan reversals during review). Of cases reaching final IMRO determination, overturn rate of treatment-denial decisions was 12.7% in 2024 (up from 10.2% in 2023). Full open-data trend file: https://data.chhs.ca.gov/dataset/independent-medical-review-imr-determinations-trend

Before external review

File the plan's internal appeal first (at least 180 days for ACA-compliant plans; the letter states the date). Ask for the claim file and the criteria the plan applied; both are free on request. Self-funded employer plans use the federal external review and the U.S. Department of Labor, not the state.

More on California: state appeal rights · External Review Index entry · insurer denial rates (HealthCare.gov states).

Verified 2026-09-15. The regulator's site and your denial notice control.