What Happens When Your Health Insurance Claim Gets Denied

A health insurance denial is not the final word, and understanding the internal appeal process is the first concrete step a policyholder can take. When an insurer rejects a claim, it must provide a written explanation that references the specific policy language or medical necessity criteria used to reach that decision. The denial letter will typically include a deadline for filing an internal appeal, often ranging from 30 to 180 days depending on the plan type and state regulations. Missing this window can forfeit the right to appeal internally, pushing the matter into external review or litigation. The internal appeal is a structured process where the insurer re-examines its own decision, often with a different reviewer who was not involved in the initial determination. For employer-sponsored plans governed by ERISA, the appeal process is governed by federal law and requires the insurer to consider any new evidence submitted by the claimant. Understanding the denial reason, whether it is a coding error, a question of medical necessity, or a coverage exclusion, shapes the strategy for the entire appeal.

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The Two-Tier Internal Appeal Structure

Most health insurance plans, including those sold on the Affordable Care Act exchanges and many employer-sponsored policies, follow a two-tier internal appeal structure. The first tier is typically called the "first-level appeal" or "reconsideration," where the policyholder or their provider submits a written request for the insurer to reverse its decision. This submission should include any additional clinical documentation, a letter of medical necessity from the treating physician, and relevant peer-reviewed literature supporting the requested treatment. The second tier is an external review by an independent review organization, but before reaching that stage, many plans require a second internal review by a senior medical director or a panel. The timeline for the first-level internal appeal is often 30 to 60 days for a decision, though some plans extend this to 180 days for non-urgent claims. For urgent claims involving hospitalization or ongoing treatment, the insurer is generally required to make a decision within 72 hours to 7 days. The second internal review, if available, may take an additional 30 days. Policyholders should keep copies of every submission, including certified mail receipts, because the paper trail becomes critical if the dispute escalates to an external review or lawsuit.

How to Prepare and Submit an Internal Appeal

Preparing an internal appeal requires assembling a comprehensive packet that addresses the specific reason for denial stated in the insurer's letter. If the denial cites "not medically necessary," the appeal should include the treating physician's detailed letter explaining the diagnosis, the failed conservative treatments, and why the requested service or medication is the standard of care. For denials based on coding errors, the appeal should include corrected billing codes and a copy of the Explanation of Benefits showing the discrepancy. The policyholder should also request a copy of the full claims file from the insurer, a right granted under ERISA and many state insurance codes, to identify any missing or misrepresented documentation. Submitting the appeal through the method specified in the denial letter, whether by mail, fax, or an online portal, and using a trackable delivery method protects the claimant's rights. The internal appeal letter should be dated and reference the claim number, the denial date, and the specific policy provisions that support coverage. Including a copy of the relevant insurance policy section, highlighted for the reviewer's convenience, can reduce processing delays. Insurers are required to acknowledge receipt of the appeal and provide a status update, though the frequency and detail of these updates vary widely.

Comparison: Internal Appeal vs. External Review vs. Litigation

FeatureInternal Appeal (Level 1 & 2)External Independent ReviewLitigation / Lawsuit
Who decidesInsurer's medical director or panelIndependent review organization (IRO)State or federal court judge
Typical timeline30–180 days per tier30–45 days after IRO selection6 months to 3+ years
Cost to claimantFreeFree (mandated by ACA for IRO)Attorney fees, court costs
New evidence allowedYes, at both levelsYes, limited to new materialYes, through discovery
Binding outcomeInsurer's final internal decisionUsually binding on the insurerCourt judgment enforceable by law
Best forCoding errors, documentation gaps, initial medical necessity disputesInsurer refuses to reverse despite strong evidenceBad faith, pattern of denials, large financial exposure
The choice between these paths depends on the complexity of the medical issue, the dollar amount at stake, and whether the insurer has acted in bad faith. Internal appeals are the mandatory first step for most plans, and skipping this step can forfeit the right to external review. External review is a free, federally protected right under the Affordable Care Act for plans issued or renewed after September 23, 2010, and many state laws extend this right to older plans as well. Litigation should be considered when the internal and external processes fail and the claim involves a significant financial or health consequence.

Common Mistakes That Derail an Internal Appeal

The most common mistake policyholders make is missing the internal appeal deadline, which is strictly enforced and rarely extended except in cases of documented incapacity. Another frequent error is submitting an appeal that merely repeats the original claim without adding new clinical evidence or a physician's detailed letter of medical necessity. Insurers often deny claims initially based on administrative or coding issues, and a resubmission without correcting those specific errors will likely result in a second denial. Failing to request the full claims file means the policyholder cannot identify if the insurer misrepresented the medical record or omitted a treating physician's note. Some policyholders rely solely on their provider's billing office to handle the appeal, but the provider's staff may lack the time or expertise to craft a legally persuasive appeal packet. Using vague language like "this treatment is important" instead of citing specific policy provisions and medical guidelines weakens the appeal. Finally, not keeping copies of every document submitted, including the envelope and postmark, leaves the claimant without proof of timely filing if the insurer claims the appeal was never received.

When to Escalate Beyond Internal Appeals

If the internal appeal is denied, the policyholder has the right to request an external review by an Independent Review Organization, a process mandated by the Affordable Care Act and reinforced by the No Surprises Act effective January 1, 2022. External review is available when the internal appeal is exhausted, and the insurer's final denial letter must inform the claimant of this right and the procedure for requesting it. The external review is conducted by a physician reviewer who is a specialist in the relevant field and who has no financial or contractual relationship with the insurer. For claims involving emergency services, the external review process is expedited, and the IRO must issue a decision within 72 hours. If the external review also denies the claim, or if the claim involves a pattern of denials suggesting bad faith, the policyholder may consider filing a complaint with the state insurance commissioner or pursuing litigation. State insurance departments have the authority to fine insurers for improper denials and can compel them to pay the claim plus penalties. Consulting with a health insurance attorney is advisable when the claim exceeds $10,000 or when the treatment is medically urgent and the delay itself poses a health risk.

The Role of AI in Navigating Health Insurance Appeals

AI-powered tools are increasingly being used to help policyholders identify the strongest grounds for an internal appeal and to generate the necessary documentation. An AI Insurance Checker can analyze a denial letter against the specific policy language, flag procedural errors in the insurer's process, and suggest the clinical evidence most likely to reverse the decision. These tools can also compare the denial reason against published medical guidelines and peer-reviewed literature to strengthen the letter of medical necessity. While AI cannot replace the judgment of a treating physician or a health insurance attorney, it can significantly reduce the time and effort required to compile a persuasive appeal packet. The use of AI in insurance appeals is still evolving, and policyholders should verify any AI-generated recommendations against their specific plan documents and state regulations. As of mid-2026, several startups and established legal tech companies offer AI-assisted appeal services, ranging from automated denial analysis to full-service appeal preparation. The key is to use these tools as a supplement to, not a substitute for, professional legal and medical advice.