When your health insurance claim is denied, you have the legal right to request an internal review of that decision. This process — called an internal appeal — is governed by federal law and gives you the opportunity to present new information and arguments before an independent reviewer within the insurance company. Understanding the process is the first step to using it effectively.

Your Legal Right to Appeal

Under the Affordable Care Act §2719 (45 CFR §147.136) and ERISA §503 (29 CFR §2560.503-1), all non-grandfathered health plans must have a meaningful internal appeals process. This right cannot be waived or limited by your plan. Key guaranteed rights include:

Step-by-Step: Filing Your Internal Appeal

Step 1: Check Your Denial Date and Deadline

Your appeal clock starts when you receive the denial notice. Most plans allow 180 days to file. Use our Deadline Calculator for your exact deadline. Don't wait — the sooner you file, the sooner you'll receive an answer.

Step 2: Request Your Claim File

Within 5-7 days of the denial, request a copy of your complete claim file from the insurer. Under 29 CFR §2560.503-1(h)(2)(iii), you're entitled to this for free. The file contains the criteria used, the reviewer's notes, and the clinical guidelines applied — all of which you'll use in your appeal.

Step 3: Identify the Specific Reason

Read your denial letter carefully and identify the exact reason(s) for denial. Use our EOB Decoder for denial codes and our Denial Checklist to check if the denial is procedurally defective.

Step 4: Gather Your Evidence

Build your evidence package: Letter of Medical Necessity from your treating physician, relevant medical records, clinical guidelines supporting your treatment, peer-reviewed studies, and documentation of prior treatments tried. The more comprehensive your package, the better your chances.

Step 5: Write Your Appeal Letter

Your appeal letter should: identify the specific denial and the reason you're challenging it; present your clinical evidence; cite applicable federal regulations; request specific relief (reversal and approval); and note your right to external review. Use our Letter Generator for a complete, regulatory-compliant template.

Step 6: Submit Your Appeal

Submit via certified mail with return receipt requested (keeps a timestamped record) OR through the insurer's online portal (get a confirmation number). Keep copies of everything. Note the submission date and the expected response deadline.

Step 7: Track and Follow Up

Your insurer must respond within required timeframes. If they don't respond on time, that constitutes a "deemed denial" you can escalate. Keep a log of all contacts with the insurer.

Response Deadlines for Insurers

Under 45 CFR §147.136 and 29 CFR §2560.503-1(f)(3), insurers must respond to internal appeals within:

What the Insurer Must Consider

The ACA requires that internal appeals be conducted as a "full and fair review." This means the reviewer:

If Your Internal Appeal Is Denied

An internal appeal denial is not the end of the road. You have the right to:

  1. File for external review — an independent review by an organization completely outside your insurer. Use our External Review Checker.
  2. File a complaint with your State Insurance Commissioner (for state-regulated plans) or the U.S. Department of Labor (for ERISA employer plans)
  3. Pursue legal action — ERISA provides a private right of action; state law provides additional remedies for state-regulated plans

Pro Tip: Don't Submit a Bare-Minimum Appeal

In ERISA litigation, courts generally limit you to the evidence that was in the administrative record during the appeal. This means your internal appeal is your best opportunity to get everything into the record. Submit all clinical evidence, studies, and arguments you have — don't save anything for "later." A thorough appeal also makes external review and litigation more effective.