Health insurance claim appeal

When a health insurance company denies a claim, you have the legal right to challenge that decision through a formal appeals process. Under the Affordable Care Act (ACA), all marketplace and most employer-sponsored plans must provide both internal appeal and external review options.

62 steps across 12 sections

1. Administrative/Billing Denials

  • Coding errors — incorrect CPT or diagnosis codes submitted by provider
  • Missing information — incomplete claim forms or missing documentation
  • Filing deadline missed — claim submitted after the plan's timely filing limit
  • Duplicate claim — insurer believes the same service was already billed
  • Coordination of benefits — insurer believes another plan is primary

2. Clinical/Coverage Denials

  • Prior authorization not obtained — treatment required pre-approval that was not secured before the service
  • Medical necessity — insurer determines the treatment was not medically necessary for your condition
  • Out-of-network provider — service performed by a provider not in your plan's network
  • Experimental/investigational — insurer classifies the treatment as unproven or experimental
  • Not a covered benefit — the specific service is excluded under your plan terms
  • Frequency limits exceeded — plan allows a set number of visits or treatments per year

3. Timeline

  • Deadline to file: 180 days (6 months) from the date you receive the denial notice
  • Insurer response time (pre-service/prospective): 30 days
  • Insurer response time (post-service/retrospective): 60 days
  • Urgent care appeals: 72 hours (expedited review)

4. Step-by-Step Internal Appeal Process

  • Identify the specific reason for denial (denial reason code)
  • Note the claim number, date of service, and amount
  • Record the appeal deadline
  • Check which section of your policy the insurer is citing
  • Original denial letter
  • Your insurance policy (Evidence of Coverage / Summary of Benefits and Coverage)
  • All medical records related to the claim
  • Bills and itemized statements
  • Notes from any phone calls with insurer or provider (dates, names, reference numbers)
  • Request a letter of medical necessity from your treating physician explaining why the treatment was appropriate and necessary

5. Eligibility

  • Medical necessity
  • Experimental/investigational treatment classification
  • Rescission of coverage (insurer retroactively cancels your policy)
  • Any denial that involves medical judgment
  • Purely administrative issues (coding errors, missed filing deadlines)
  • Services explicitly excluded from your plan with no medical judgment involved

6. Timeline

  • Deadline to request: 4 months from the date you receive the final internal appeal denial
  • Standard review decision: Within 45 days of the request
  • Expedited review (urgent medical situations): Within 72 hours

7. How It Works

  • File external review request with your insurer or state insurance department (your denial letter will specify the process)
  • An Independent Review Organization (IRO) is assigned to your case
  • The IRO assigns medical experts in the relevant specialty to review your case
  • The IRO reviews all medical records, policy language, and clinical evidence
  • The IRO issues a binding decision
  • If the IRO overturns the denial, the insurer must pay the claim

8. Cost

  • Federal external review process (HHS-administered): No charge
  • State external review process: May charge up to $25 per review
  • IRO contracted by insurer: May charge up to $25

9. Required Information

  • Full legal name (exactly as it appears on insurance card)
  • Member ID and group number
  • Claim number being appealed
  • Date of denial letter
  • Denial reason code

10. Provider Information

  • Full legal practice name
  • Provider credentials and specialty
  • National Provider Identifier (NPI)
  • Complete address, phone, and fax

11. Supporting Documentation

  • Letter of medical necessity from treating physician
  • Relevant medical records and clinical notes
  • Lab results, imaging, and test reports
  • Published clinical studies or practice guidelines supporting the treatment
  • Prior treatment history showing alternatives that were tried and failed
  • Peer-reviewed journal articles (if denial cites "experimental")
  • Your plan's Summary of Benefits showing the service should be covered

12. When You Qualify

  • Waiting for a standard appeal timeline could seriously jeopardize your life, health, or ability to regain maximum function
  • You are currently receiving treatment that is about to be discontinued
  • You have not yet received a service that your doctor says is urgently needed

Common Mistakes

  • Not appealing at all
  • Missing the deadline
  • Submitting a vague or emotional appeal
  • Not including a physician letter
  • Sending original documents

Pro Tips

  • Act immediately
  • Call your insurer first
  • Request your complete claims file
  • Use the insurer's own criteria against them
  • Reference clinical practice guidelines

Sources

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