Prior Authorization

Medicare Denied Prior Authorization Request

Name: Medicare Denied Prior Authorization Request
Creator: Barley Billing Team
Published: 2026-03-26

Written by Barley Billing Team, Medicare Billing Experts | Last reviewed March 26, 2026

Does your notice say something like this?

"Services denied at the time authorization/pre-certification was requested"

"The requested service has not been approved"

"Prior authorization request denied"

If so, you're in the right place. Here's what it means and what to do.

What This Means

Your health plan reviewed your provider’s request for prior authorization and decided not to approve the service. This means the plan won’t cover the cost of this service at this time.

This is different from a claim denial. A prior authorization denial happens before you receive the service. The good news is that you have the opportunity to appeal before any bills are involved.

Why This Happens

The plan didn’t find the service medically necessary. Based on the information submitted, the plan determined the service doesn’t meet their criteria for medical necessity for your condition.
The documentation was incomplete. Your provider may not have included enough clinical information to support the request. This is one of the most common and fixable causes.
The plan requires a different treatment first. Some plans use “step therapy,” which means they require you to try a less expensive treatment before approving the requested one.
The service isn’t covered under your plan. The service may be excluded from your specific plan’s benefits, separate from the prior authorization question.
Coding or administrative errors. The wrong diagnosis code, procedure code, or other administrative details on the request can trigger a denial.

Should You Appeal?

Appeal outlook: Mixed

Prior authorization denials are worth appealing, especially when your doctor believes the service is necessary. A 2022 OIG investigation found that 13% of Medicare Advantage prior authorization denials would have been approved under Original Medicare’s standard coverage rules. That means some services are being denied by MA plans even though Medicare would normally cover them.

When people do appeal, the results are encouraging. KFF (2024) found that approximately 81% of appealed prior authorization denials in Medicare Advantage were fully or partially overturned.

Your appeal is strongest when your doctor provides detailed clinical documentation explaining why this specific service is needed for your condition.

What To Do Next

Talk to your doctor right away. Ask them to review the denial reason and provide additional documentation supporting why the service is medically necessary. A detailed letter from your doctor can make a significant difference.
Ask about a peer-to-peer review. Your provider can often request to speak directly with a medical director at your plan to discuss the case. This is an informal but sometimes effective step before or during the formal appeal.
File an appeal promptly. Follow the instructions on your denial notice. For Medicare Advantage plans, standard appeals must be decided within 30 days. If waiting could harm your health, request an expedited appeal (decided within 72 hours).
Ask about alternative treatments. If the plan denied the specific service, ask your doctor whether there’s an alternative that the plan would cover. You can pursue the alternative while also appealing for the original service.
Request the plan’s clinical criteria. You have the right to ask your plan for the specific guidelines they used to make their decision. This helps you understand exactly what documentation is needed for a successful appeal.
Get help if you need it. Your State Health Insurance Assistance Program (SHIP) offers free counseling and can help you with the appeal process. Call 1-800-MEDICARE (1-800-633-4227) to find your local SHIP.

Sources

Want us to review your denial for free? Send us your notice and we'll tell you if it's worth appealing →

Appeal Deadlines — Check Your Notice for Exact Dates

Original Medicare

120 days from the date on your MSN

Medicare Advantage

At least 60 days (check your denial notice for exact deadline)

Not sure which you have? Check the top of your denial notice. If it names a private insurance company (like Humana, UnitedHealthcare, or Aetna), you have Medicare Advantage. If it says "Centers for Medicare & Medicaid Services," you have Original Medicare.

Frequently Asked Questions

What's the difference between a prior auth denial and a claim denial?

A prior authorization denial happens before the service is provided. Your plan is saying it won't approve the service in advance. A claim denial happens after the service is provided. The important distinction is that with a prior auth denial, you can appeal before receiving (and paying for) the service.

Can my doctor still provide the service if the prior auth was denied?

Yes, but you would likely have to pay the full cost out of pocket. It's usually better to appeal the prior authorization denial first. If the appeal succeeds, the service will be covered.

How quickly will my appeal be decided?

For Medicare Advantage plans, standard prior authorization appeals must be decided within 30 calendar days. If your health could be seriously harmed by waiting, you or your provider can request an expedited appeal, which must be decided within 72 hours.

What if my doctor says I need this service urgently?

Ask your provider to request an expedited appeal. Medicare Advantage plans must process these within 72 hours. Your doctor can also request a peer-to-peer review, which means they speak directly with a medical director at your plan to discuss why the service is needed.

Want Us to Check Your Denial?

Send us your denial notice and we'll review it for free. We'll tell you if it's worth appealing and exactly how to do it.

This information is for educational purposes only and is not legal or medical advice. Always verify with your doctor's office and insurance company.