The 10 Most Common Prior Authorization Denial Reasons (And How to Overturn Them)

Understanding Your Denial

When a prior authorization is denied, the denial letter contains a reason code and explanation. Most denials fall into a small number of categories, and each one requires a different approach to overturn.

The 10 Most Common Denial Reasons

1. Medical Necessity Not Demonstrated

What it means: The reviewer determined that the clinical documentation didn't establish why this specific service is needed for this specific patient.

How to overturn it: Focus on the individual patient's clinical picture. Document failed alternatives, progression of symptoms, and how the requested service addresses the specific clinical need. Reference the payer's own medical policy if available.

2. Incomplete Documentation

What it means: The submitted records were missing information the reviewer needed to make a determination.

How to overturn it: This is often the easiest to overturn. Identify what's missing, gather it, and resubmit. Common gaps: operative reports, imaging reports, specialist notes, or documentation of conservative treatment.

3. Service Not Covered Under Plan

What it means: The patient's specific plan doesn't include coverage for the requested service, regardless of medical necessity.

How to overturn it: Verify the patient's benefits first. If the service truly isn't covered, a P2P won't help. If there's a coverage exception process, pursue that instead.

4. Out-of-Network Provider

What it means: The service was requested from a provider not in the patient's network.

How to overturn it: Document why an in-network provider cannot perform the service (specialization, geography, wait times). Many payers have network adequacy requirements.

5. Alternative Treatment Available

What it means: The reviewer believes a less costly or less invasive alternative should be tried first (step therapy).

How to overturn it: Document why alternatives are inappropriate for this patient. Prior failures, contraindications, or clinical urgency can all support bypassing step therapy.

6. Criteria Not Met (InterQual/MCG)

What it means: The case doesn't meet the specific clinical criteria in the payer's screening tool.

How to overturn it: Know which criteria set they're using and which specific criterion wasn't met. In the P2P, present additional clinical context that may not have been captured in the initial review.

7. Frequency/Duration Exceeded

What it means: The patient has exceeded the payer's limit on the number of sessions or duration of a service.

How to overturn it: Document ongoing medical necessity, measurable progress, and why additional sessions are needed to achieve clinical goals.

8. Experimental/Investigational

What it means: The payer considers the requested service to be experimental.

How to overturn it: Provide published peer-reviewed literature, professional society guidelines, and FDA approvals that support the service as standard of care.

9. Coding Error

What it means: The diagnosis or procedure codes submitted don't support the request.

How to overturn it: Review the codes with your billing team. Often a simple correction and resubmission resolves the issue without needing a P2P.

10. Timely Filing

What it means: The prior auth request was submitted outside the payer's required timeframe.

How to overturn it: Document the reason for the delay and file a timely filing appeal. Some payers have exceptions for urgent or emergent situations.

When to Request a P2P

Not every denial requires a P2P call. P2P reviews are most effective for denials based on medical necessity (#1), criteria not met (#6), and alternative treatment available (#5). For coding errors or timely filing issues, administrative appeals are usually more appropriate.

*Denied and need to prep for a P2P? Use our free tool to generate a structured script in 60 seconds. Or look up your denial code for specific guidance.*