How to Appeal a Health Insurance Denial
A denial is a decision, not the end of the process. Most plans must offer an internal appeal and, if that fails, an independent external review. Deadlines are strict, so the first step is reading the denial letter carefully.
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Educational information only — not medical advice. In an emergency, call 911.
Quick answer: when to seek care
Find the denial reason code and the appeal deadline in your denial letter, then file an internal appeal in writing. If it is denied again, request an independent external review.
Red flags and urgency levels
- UrgentSeek care today
A denial for care you need urgently — ask for an expedited appeal, which has a much shorter timeline.
- SoonMake an appointment within days to a couple of weeks
An appeal deadline approaching (often 180 days from the denial notice).
- SoonMake an appointment within days to a couple of weeks
A denial reason that appears to be a coding or paperwork error rather than a coverage decision.
- MonitorKeep track and mention it at your next visit
A denial you accept, where an in-network alternative is available.
Common context
- Common denial reasons: missing prior authorization, out-of-network provider, coding errors, or a 'not medically necessary' determination.
- Most plans provide an internal appeal, then an external review by an independent third party whose decision is binding on the plan.
- Your clinician's office can often supply a letter of medical necessity and supporting records.
What you can do next
- 1
Request the full denial rationale and the plan's clinical criteria in writing.
- 2
Write a short appeal letter: what was denied, why it is needed, and which plan criteria it meets.
- 3
Attach supporting records, clinical notes, and a letter of medical necessity.
- 4
Send it with proof of delivery and track every deadline in one place.
- 5
Contact your state insurance department or consumer assistance program if the plan is unresponsive.
Questions to ask a clinician
- “Can your office write a letter of medical necessity for this?”
- “Which clinical records support the appeal, and can they be sent directly?”
- “Was prior authorization required, and was it submitted?”
- “Is there an equivalent covered alternative if the appeal fails?”
- “Can you request a peer-to-peer review with the plan's medical director?”
Reliable sources
- Appealing a Health Plan DecisionHealthCare.gov
- External ReviewCenters for Medicare & Medicaid Services
- Internal Claims and AppealsU.S. Department of Labor
Medical disclaimer
HealthcareConcern provides general health information for educational purposes only. It is not medical advice, diagnosis, or treatment, and it is not a substitute for care from a qualified clinician. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition. If you think you may have a medical emergency, call 911 or your local emergency number immediately.
Reviewed and updated . We review each guide regularly against primary sources.