What Is Your Right to External Review of Insurance Denials?

When your insurer denies your appeal and upholds its decision, most people assume the process is over. It is not. Federal law and most state laws give you the right to an independent External Independent Review: Complete Guide" class="auto-link">external review of your denial—a process where an independent organization, completely separate from your insurer, evaluates whether the denial was correct. If they say it was not, the decision is binding on your insurer.

External review is one of the most powerful—and underused—rights in health insurance. The reversal rate is significant: studies have found that patients win their external reviews at rates ranging from 30% to 60%, depending on the denial type and state.

What Is External Review?

External review is an appeals process conducted by an IROs) Explained" class="auto-link">Independent Review Organization (IRO)—a certified, accredited third-party entity that has no financial relationship with your insurer. The IRO reviews your case de novo (from scratch), applying clinical evidence and applicable standards—not just your insurer's coverage policy.

The external reviewer's decision is binding on your insurer. If the IRO says your treatment should be covered, your insurer must cover it—regardless of their own internal policy or prior decision.

Federal vs. State External Review Programs

There are two external review systems in the United States:

State-based external review. Most states have their own external review programs, administered by the state insurance department. These programs apply to fully-insured plans (including marketplace and individual plans). State programs vary in scope, timelines, and eligible denial types.

Federal external review. The ACA established a federal external review process for plans that are not covered by state programs—primarily ERISA self-funded employer plans. The federal program uses IROs accredited by URAC or NCQA. CMS oversees the program.

In most cases, your insurer's denial letter will specify which program applies to you.

What Denials Are Eligible for External Review?

Under federal ACA standards, external review is available for:

• Medical necessity denials. The most common category—treatment not deemed medically necessary under the insurer's criteria.
• Experimental and investigational denials. Treatments the insurer labels as experimental or not proven.
• Rescission decisions. Retroactive cancellation of coverage (except for nonpayment of premiums).
• Denials involving an adverse benefit determination based on medical judgment

Pure coverage exclusions—cases where the plan simply does not cover a category of service and no medical judgment is involved—may not be eligible for external review under all state programs. Check your denial letter and your state's specific rules.

How to Request External Review

Step 1: Exhaust your internal appeals. External review is generally only available after you have completed the insurer's internal appeal process—or after a certain number of internal levels have been completed. (For urgent situations, some programs allow concurrent external review.)

Step 2: Check your deadline. You typically have 4 months from the date of your final internal denial to request external review under federal rules. State programs may have different—sometimes shorter—deadlines. Do not miss this window.

Step 3: Submit the request. You can usually request external review in writing, by phone, or online. Your denial letter should explain how to request external review. If it does not, call your state insurance department or the federal appeals center listed in your denial.

Step 4: Provide your documentation. Submit all supporting materials: your physician's letters, medical records, clinical studies, prior appeal submissions and insurer responses. The IRO reviews the whole record.

Step 5: Wait for the decision. Standard external review decisions are issued within 45 days under federal rules. Expedited external review—for urgent, life-threatening situations—must be decided within 72 hours.

The IRO Review Process

The IRO assigns your case to one or more clinical reviewers with relevant medical expertise. They are required to:

• Review all submitted documentation
• Apply generally accepted clinical, scientific, and medical standards
• Be independent of your insurer and plan
• Consider clinical practice guidelines from major professional societies

The IRO does not defer to the insurer's internal coverage policy. Their standard is clinical appropriateness, not the insurer's administrative determination.

What Happens If You Win

If the IRO reverses the denial, your insurer must cover the service immediately. They cannot re-deny it based on the same reasoning or appeal the IRO's decision. If claims were already paid out of pocket, the insurer must reimburse you.

What Happens If You Lose

If the IRO upholds the denial, you have limited further options through the insurance system. For ERISA plans, you may pursue a federal court lawsuit. For fully-insured plans, state court action or an insurance commissioner complaint may be available. Given the cost of litigation, consulting an insurance attorney makes sense for large-dollar disputes.

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Related Reading:

• How to Write an Insurance Appeal Letter
• What Is Medical Necessity?
• Internal vs External Insurance Appeal