Medicare Prior Authorization Denied: How to Appeal

Prior Authorization Denied: How to Appeal" class="auto-link">Prior authorization (PA) is one of the most contentious tools Medicare Advantage plans use to control costs — and one of the most abused. If your Medicare Advantage plan has denied a prior authorization request, you are not without options. Federal regulators have been cracking down on inappropriate PA denials, and your appeal rights are strong.

What Is Prior Authorization in Medicare Advantage?

Original Medicare (Parts A and B) does not require prior authorization for most services. Medicare Advantage plans, however, operate differently. As private insurers, MA plans are allowed to require PA for services they deem high-cost or high-risk, including surgeries, specialist visits, imaging (MRI, CT), infusion therapy, and hospital stays.

PA means the plan must approve the service before it is provided. When a plan denies that approval, it is called a prior authorization denial — and it can block access to medically necessary care.

CMS and OIG Have Found Major Problems

The Office of Inspector General (OIG) released reports documenting that Medicare Advantage plans frequently deny prior authorization requests for services that meet Medicare coverage rules. In one landmark 2022 OIG report, 13% of prior authorization denials were for services that should have been approved under Original Medicare criteria.

In response, CMS issued its 2024 Prior Authorization Rules for Medicare Advantage plans, effective January 2024. Key provisions include:

• Continuity of care: Plans cannot require new PA for ongoing treatment when a patient switches plans mid-year
• PA valid for the duration of treatment: Plans cannot require repeated PA for the same ongoing condition
• Automated PA systems must use Medicare coverage criteria, not more restrictive plan-specific criteria
• Denial notices must explain the specific clinical reason for denial, not just cite a general policy
• Timeframes: 72 hours for urgent PA requests; 7 calendar days for standard requests

If your plan is violating any of these requirements, your denial may be legally defective.

Peer-to-Peer Review: A Powerful First Step

Before filing a formal appeal, ask for a peer-to-peer (P2P) review. This is a direct phone call between your treating physician and the plan's medical reviewer. P2P reviews are not required by CMS but are offered by most MA plans.

During a P2P call, your doctor can:

• Explain the clinical rationale the plan's reviewer may have missed
• Cite medical literature supporting the requested service
• Clarify why alternatives the plan suggested are clinically inappropriate for you specifically

Many PA denials are overturned at the P2P stage. If the P2P fails, proceed to formal appeal immediately.

The Formal Appeal Process for PA Denials

Step 1 — Redetermination (Level 2) File your redetermination request within 60 days of the denial. For urgent requests, ask for an expedited redetermination — the plan must respond in 72 hours. Submit your physician's full clinical notes, relevant test results, and a letter explaining medical necessity.

Step 2 — Independent Review Entity (Level 3) If the plan upholds the denial, escalate to the IRE within 60 days. The IRE is a CMS-contracted independent organization that reviews the plan's decision without deference to the plan's judgment. IRE decisions are binding on the plan.

Step 3 — ALJ Hearing (Level 4) If the IRE upholds the denial and the amount in controversy is sufficient, request an ALJ hearing within 60 days. ALJ hearings allow you to present evidence and testimony.

Step 4 and 5 — MAC and Federal Court The Medicare Appeals Council and federal district court remain available for unresolved disputes.

What Documentation Strengthens a PA Appeal

• A detailed letter of medical necessity from your treating physician
• Peer-reviewed clinical guidelines supporting the requested service (e.g., NCCN guidelines for cancer care, ACC guidelines for cardiac procedures)
• Documentation that the plan's preferred alternative has already been tried and failed, or is clinically contraindicated
• Your complete relevant medical records
• The plan's specific denial language (to rebut it point by point)

Filing a CMS Complaint About PA Abuse

If you believe your plan is systematically denying PA requests improperly, file a complaint with CMS. CMS has authority to sanction MA plans and has done so repeatedly. File at medicare.gov/talk-to-someone or call 1-800-MEDICARE.

You can also contact your SHIP counselor (shiphelp.org) for free guidance on navigating PA disputes.

The Key Rule to Remember

Medicare Advantage plans are required by law to apply Medicare coverage criteria — not more restrictive plan-developed criteria — when making PA decisions. If your plan denied a PA for a service that Original Medicare covers, that denial may violate CMS rules. Make that argument explicitly in your appeal.

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Related Reading:

• How to Write an Insurance Appeal Letter
• What Is Medical Necessity?
• Internal vs External Insurance Appeal