How to Appeal a Health Insurance Claim Denial

You Have the Right to Appeal

If your health insurer denies a claim or prior authorization request, you have a legal right to appeal that decision. Studies show that a significant percentage of internal appeals result in the denial being overturned — especially with proper documentation.

💡 Don't just accept a denial. Between 30–50% of appealed denials are overturned. The process takes time but is often worth pursuing, especially for large claims.

Step 1 — Understand Why the Claim Was Denied

Your denial letter must explain the reason. Common reasons include:

Not medically necessary
Service not covered by your plan
Prior authorization not obtained
Out-of-network provider
Coding error (often fixable quickly)

Step 2 — Internal Appeal

File an internal appeal with your insurer within the deadline (typically 180 days from the denial). Include:

A written appeal letter referencing the claim number
Supporting documentation from your doctor stating medical necessity
Relevant medical records
Any clinical guidelines supporting the treatment

Step 3 — External Review

If your internal appeal is denied, you can request an external review by an independent organization. Your insurer must abide by the external reviewer's decision. This is often the most powerful step.

Step 4 — State Insurance Commissioner

If external review fails, file a complaint with your state's Department of Insurance. They have authority to investigate and act against insurers who improperly deny claims.

Key Deadlines

Internal appeal: Usually within 180 days of denial notice
Expedited appeal (urgent situations): Insurer must respond within 72 hours
External review request: Usually within 4 months of internal appeal denial

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Frequently Asked Questions

How long does an insurance appeal take?

Internal appeals typically take 30–60 days for standard cases and 72 hours for urgent/expedited appeals. External review decisions are typically issued within 45 days, or 72 hours for urgent cases.

Should I hire someone to help with my appeal?

Patient advocates and healthcare billing advocates can be very effective but charge fees. For large claims (surgery, hospital stays), it may be worth the cost. For smaller claims, a well-documented self-filed appeal is usually sufficient.

What is a peer-to-peer review?

A peer-to-peer review is when your doctor calls the insurer's medical director to discuss the clinical basis for the denied treatment. This is often the most effective first step when a prior authorization is denied for medical necessity reasons.