Prior authorization denials: how to overturn them
Prior authorization denials are among the most reversible decisions in health insurance, because they are usually made against a checklist rather than against your chart. A well-structured appeal supplies the missing checklist item — and a large share of appealed denials get overturned.
Why the denial happened
Most prior authorization denials fall into a few narrow buckets, and each has a specific fix. Get the exact reason in writing before you write anything: call the insurer and ask for the denial letter and the clinical criteria they applied.
- Not medically necessary under the plan's clinical criteria
- Step therapy — a cheaper treatment must be tried first
- Missing documentation from the ordering clinician
- Coding or site-of-service mismatch (e.g., inpatient vs. outpatient)
- Out-of-network provider or facility
- Authorization requested after the service was performed
Start with a peer-to-peer review
Before a formal appeal, your clinician can request a peer-to-peer: a direct call with the insurer's medical reviewer. It is fast, it often resolves the denial on the call, and it puts a clinician's reasoning against the checklist. Ask your doctor's office to request it and to note the reviewer's name and the outcome.
Write the appeal around their own criteria
The winning appeal quotes the insurer's clinical policy back to them and shows, point by point, how your record meets it. Attach chart notes, prior treatment history, imaging or lab results, and a letter of medical necessity from the ordering clinician.
If the denial was step therapy, document what you already tried, when, and why it failed or was contraindicated. If it was documentation, supply exactly the missing item and say so in the first sentence.
- Reference the member ID, authorization/reference number, and denial date
- Quote the plan's own criteria and map your evidence to each element
- Include a letter of medical necessity signed by the ordering clinician
- State the outcome you want and a response deadline
Expedited appeals and external review
If waiting would seriously jeopardize your health, request an expedited appeal — decisions come in as little as 72 hours. If the internal appeal is denied, request an independent external review; the reviewer is not employed by the insurer and their decision binds the plan.
Keep a dated log of every call, name, and reference number. Regulators and external reviewers weigh a documented timeline heavily.
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Start freeFrequently asked questions
- How often are prior authorization denials overturned?
- A large share of appealed denials are reversed — which also means most denials are never appealed at all. Filing a structured appeal with clinical documentation is the single highest-value action.
- What is a peer-to-peer review?
- A direct conversation between your treating clinician and the insurer's medical reviewer. It's faster than a written appeal and frequently resolves the denial without one.
- Can I appeal if the service already happened?
- Yes. A retrospective review or post-service appeal is possible, though you'll need documentation of why authorization wasn't obtained in advance — urgency and emergency are common valid reasons.
- What's an expedited appeal?
- An accelerated review when a delay would seriously jeopardize your health or ability to regain function. Decisions typically come within 72 hours; ask for it explicitly and have your clinician support the request.
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Informational tool — not legal, medical, or financial advice.