Insurance denials

Insurance denied for 'not medically necessary' — your appeal rights

When an insurer denies a claim as 'not medically necessary,' that's a determination — not a final answer. Federal law gives every covered patient the right to two levels of internal appeal and one independent external review. Most denials reversed on appeal involve documentation the insurer didn't have at the time of the initial decision.

Federal basis

ERISA + ACA appeals rights

ERISA §503 (29 USC §1133) / ACA §2719 (42 USC §300gg-19)

Read the source →

What this looks like in practice

ERISA §503 (for employer plans) and ACA §2719 (for non-grandfathered individual / small group plans) require insurers to provide: (1) written denial with the specific reason and the claim file the insurer relied on, (2) at least one level of internal appeal (most plans offer two), (3) for non-grandfathered plans, an independent external review by a state-certified IRO or HHS-certified federal IRO. The plan must follow specific timelines: 30 days for pre-service decisions, 60 days for post-service. Appeals require the plan to consider any new evidence the patient submits.

The most successful appeal strategy: get the medical record, the claim file, and the relevant clinical guideline (LCD, NCD, or specialty society guideline), then write an appeal that maps the documented care to the criteria the insurer applied. Plans reverse a meaningful share of medical-necessity denials when presented with this kind of structured appeal.

How to spot it on a bill

  • 01.Claim denied with a code like 'not medically necessary,' 'experimental/investigational,' or 'inappropriate setting.'
  • 02.Initial denial letter cites a specific medical-necessity criterion.
  • 03.Service was actually rendered and documented in the medical record.

What to write — ready-to-paste language

Replace the bracketed fields with your specific details. Send by certified mail with return receipt, or via the hospital’s patient portal if it offers documented messaging. Keep a copy.

I am appealing the denial of claim [number] for service on [date]. The denial cites [reason]. I have attached: (1) the relevant entries from my medical record showing the documented clinical indication, (2) the [LCD/NCD/specialty guideline] that establishes medical necessity for this indication, and (3) my treating provider's note explaining why the service was appropriate. Per ERISA §503 / ACA §2719, please review this appeal and respond within the regulatory timeline. If the appeal is denied at the internal level, please confirm my right to external review and the process for requesting it.

This is a starting point, not legal advice. Your specific situation may warrant additional details. Our scan tool drafts this letter automatically with your bill’s specifics filled in.

Skip the manual review

Our scan checks every line of your bill against this and 20+ other patterns — in 60 seconds.

Upload a photo or PDF of the bill. Every charge cross-referenced against four federal data sources, every flagged pattern paired with the right dispute letter pre-drafted with the citations and the math already inside. You sign, you mail.

  • ✓Up to 5 dispute letters drafted, including this one if it applies.
  • ✓Charity-care application drafted if your hospital is non-profit.
  • ✓Federal-statute citations & line-item math automated.
  • ✓We Found Something or You Don’t Pay.
Analyze my bill — $19.9730-day money-back. No account needed to start.

Common questions

How long do I have to appeal?
Most plans give 180 days from the denial letter to submit an internal appeal. Self-funded ERISA plans may set their own deadlines but cannot be shorter than the regulatory minimum. The plan document or summary plan description has the specific deadline.
Do I need a lawyer to appeal?
For most denials, no — patients can self-appeal effectively. The plan must consider any evidence you submit. State insurance departments often have free Consumer Assistance Programs that help with appeals at no cost. For high-value denials (e.g., large surgery, cancer care), a healthcare attorney can substantially improve outcomes.
What happens if external review is denied?
External review by a federally-certified IRO is binding on the insurer. If external review still denies, the next step depends on the plan type — ERISA plans go to federal court (ERISA §502); fully-insured plans go to state court or the state insurance commissioner.

P.S. The dispute language above is a starting point. Bills with this pattern often have additional issues alongside it — coding errors stacked with markup, surprise bills stacked with charity- care eligibility. The scan finds all of them in one pass. Start the audit →

P.P.S.Federal law gives you these rights regardless of how the bill arrived. Insured, uninsured, in-network, out-of-network — the underlying patient-protection statutes apply.

P.P.P.S. Bills are time-sensitive. Most insurance appeals must be filed within 180 days. Charity-care discounts at non-profit hospitals are most easily applied within 240 days of the original bill. Acting earlier costs less.