Headline numbers
Overturn rate by state
| Jurisdiction | Cases / year | Overturn rate | Median days to decision | Source |
|---|---|---|---|---|
| Federal-HHS aggregate | 1,200 | 44% | 45 days | CMS CCIIO Federal External Review Fact Sheet (2022) |
| California | 2,827 | 68% | 30 days | California DMHC Annual Report / IMR Summary (2023) |
| New York | 12,042 | 46% | 30 days | NY DFS Annual Report / Consumer Guide (2023) |
| Illinois | 842 | 51% | 21 days | Illinois DOI OCHI Annual Report (2023) |
| New Jersey | 510 | 45% | 45 days | NJ DOBI IHCAP Reports (2023) |
| Pennsylvania | 980 | 50% | — | Pennsylvania Insurance Department Annual Report (2023) |
| Massachusetts | 228 | 45% | 14 days | HPC Office of Patient Protection Annual Report (2022) |
| Maryland | 812 | 44% | 30 days | Maryland Office of the Attorney General HEAU Annual Report (2023) |
| Connecticut | 145 | 80% | 30 days | Connecticut Insurance Department Consumer Report Card (2023) |
Verified 2026-06-16. States not listed either defer to the federal-HHS process or do not publish granular annual outcome statistics; those cases roll up into the federal aggregate.
States that use the federal-HHS process
Roughly half of US states use the federal Department of Health & Human Services external review process, administered by MAXIMUS Federal Services. When you file, your case is assigned to an Independent Review Organization (IRO) that reports back to HHS. The federal aggregate overturn rate has averaged around 44% over recent years, though this is skewed by carrier and denial reason.
For a state-by-state list of who administers external review and how to file, see External review by state.
How external review works
- You must first exhaust your insurer's internal appeal (usually one or two levels).
- You have at least 4 months from the final internal denial to file (45 CFR 147.136(d)(2)(ii)).
- An IRO physician in the relevant specialty reviews the full clinical record.
- The IRO decision is binding on the insurer.
- Median decision time runs 14–45 days depending on the state.
Methodology
Per-state figures are sourced from each state's Department of Insurance / Department of Managed Health Care annual report, or the Office of Consumer Health Insurance where applicable. The federal-HHS aggregate is drawn from the CMS CCIIO Federal External Review Fact Sheet. Numbers are re-verified quarterly and cross-checked against the linked primary source.
Upload your final internal denial. We'll prepare the IRO request under 45 CFR 147.136(d) with the clinical evidence attached.