Key Takeaways

  • If you were denied coverage by Medicare for a health service or item, you have the right to appeal the decision.

  • There is more than one level of appeal, and you can continue appealing if you are not successful at the first level.

  • A letter of support and documentation from your doctor can help you create a strong appeal that increases your odds of success.

Were you denied coverage for an important health service or item by original Medicare, Medicare Advantage (Part C), or Medicare Part D (prescription drug coverage)? First of all, don’t panic—you have the right to appeal the decision. In 2021, more than 2 million prior authorization requests were fully or partially denied by Medicare Advantage insurers. Only 11% of denials were appealed by enrollees.

What is the success rate of Medicare appeals? Most (82%) appeals resulted in Medicare fully or partially overturning the initial prior authorization denial.1

Considering the process is often successful, appealing a Medicare coverage denial is worth the time and effort. In this guide, we explore common reasons for denial, how to start the appeal process, and tips for a successful appeal.

What is a Medicare denial?

Medicare denials happen when Medicare does not agree to pay for a health care service or item you've received. Medicare may also:

  • Deny a request for a certain health care service, item, supply, or medication you think should be covered by your Medicare plan (but have not received)
  • Deny a request to change the amount you must pay for a health care service, item, supply, or medication

What are the reasons for Medicare denial?

There are many reasons Medicare might deny you coverage. Some common ones include:

  • Medicare feels the service was not medically necessary.
  • You've exceeded the maximum allowed days in a hospital or care facility.
  • You used a provider outside of your provider network (only with Medicare Advantage plans).
  • Your Part D plan's formulary does not include your medication.
  • A certain health care service, supply, or item is no longer covered by your Medicare plan.

What happens if you are denied Medicare coverage?

When Medicare denies coverage, they will issue you a Medicare denial letter.

  • If you have original Medicare, you should receive Medicare Summary Notices (MSNs). MSNs are usually mailed quarterly after you receive health care services. If you receive no health care services in a certain quarter, you will not receive an MSN. Note: If you lose an MSN and need a duplicate, log into your Medicare account at
  • If you have a Medicare Advantage plan, you should receive Explanation of Benefits notices (EOBs). EOBs are typically mailed out once per month, or per service. Note: If you lose an EOB and need a duplicate, call your plan directly. The number should be located on the back of your health insurance card.

MSNs and EOBs are not bills—they are summaries of the care you received during a timeframe, how much the provider billed, the amount your insurance will pay, and how much you may owe the provider. If you are denied a medical service or item, it should be listed on your MSN or EOB, along with a reason for the denial. 

TIP: Understanding the reason for denial is important to your appeal. If you are confused about the reason for denial, you should call 1-800-MEDICARE (if you have original Medicare) or your Medicare Advantage plan to learn more about the denial. You can also contact your State Health Insurance Assistance Program (SHIP) for help at no cost. Find your local SHIP by visiting the website or calling 877-839-2675.

What is a Medicare appeal?

An appeal is a formal request for a review of a decision made by original Medicare or a private Medicare Advantage or Part D plan. There is more than one level of Medicare appeal, and you can continue appealing if you are not successful at first. Be aware that each level of appeals has its own timeframe for when you must file the appeal.

How do I start an appeal for a denial from original Medicare?

Start your appeal by following the appeal instructions listed on your MSN. This includes circling the denied service listed and filling out the shaded section at the end of the MSN. Then, send your appeal to the Medicare Administrative Contractor (MAC) within 120 days of the date on your MSN. (The MAC’s name and address are listed in the shaded section of your MSN.) This will start your appeal. The MAC should make a decision within 60 days. If the appeal is successful, the service or item will be covered.

You can file a Medicare coverage denial appeal yourself, or you can contact your local SHIP for help.

How do I start an appeal for a denial from my Medicare Advantage plan?

First, begin by ensuring you have a written denial notice in hand. If you do not yet have one, you can contact your plan. Otherwise:

  • If you have already received the care that is being denied, you should have the denial on your EOB. An appeal of this decision is called a “post-service appeal.”
  • If the denial is for a service or item that you have not yet received, you should get a Notice of Denial of Medical Coverage from your plan. An appeal of this decision is called a “pre-service appeal.”

Start the appeal by following the instructions on the notice. The appeal should be filed within 60 days of the date on the notice. It will most likely require you to send a letter to the plan, explaining why the care is/was needed. You should ask your doctor for help drafting this letter. 

Once you file an appeal, you must wait the standard timeframe for a response:

  • For a post-service appeal, your plan should make its decision within 60 days. 
  • For a pre-service appeal, the plan should decide within 30 days.

TIP: If you are filing a pre-service appeal (meaning you were denied coverage for an item or service you have not yet received), you can request an expedited appeal if the matter is urgent. An appeal can be expedited if you or your doctor feels your health could be seriously harmed by waiting the standard timeline for appeal decisions. If your plan approves your request to expedite, it should issue a decision within 72 hours.

How can I start an appeal for a denial from my Part D plan?

When you get your prescription drugs from a pharmacy, you may be told your Medicare Part D drug plan has denied you coverage. You have the right to appeal this decision. See our complete guide to Part D appeals here.

What can I do if my first Medicare appeal is denied?

If your appeal is denied at the first level, you have the right to continue appealing. People whose appeals are initially denied may find success at later stages of the process. Instructions for how to file your next appeal will be on the notice of denial you receive. Remember that each level has its own timeframe for when you must file an appeal and when you should receive a decision, so make sure you are filing in a timely manner. 

TIP: In later levels of appeal (such as if your appeal is with the Office of Medicare Hearings and Appeals [OMHA], the Council, or the Federal District Court), you may wish to talk a lawyer for help. While you’re not required to have representation, these later levels of appeal can be more complex, and expert assistance can be useful.

See the infographic below for an illustration of the appeals process.

Can I still file a Medicare coverage denial appeal if I miss a deadline?

Maybe. If you can show good cause for not filing on time, your late appeal may still be considered. You can request a "good-cause extension" at any level of appeal and whether you have original Medicare or Medicare Advantage. This can be done simply by sending in your appeal as you normally would and including a clear explanation of why the appeal is late.

Extensions are considered on a case-by-case basis, so there is no complete list of acceptable reasons for filing a late appeal. But some examples may include:

  • The notice being appealed was mailed to the wrong address.
  • Illness (either yours or a close family member’s) prevented you from handling business matters.
  • A Medicare representative gave you incorrect information about the claim being appealed.

TIP: If the reason has to do with illness or other medical conditions, including a letter or supporting documentation from your doctor can be helpful.

Can someone file a Medicare coverage denial appeal on my behalf?

Yes. If you're unable to do it on your own, you can appoint a representative to appeal a denial on your behalf. To appoint a representative, complete the Appointment of Representative form and mail it to either your MAC (if you have original Medicare) or your Medicare Advantage plan.

Or, rather than complete this form, you can submit a written request alongside your appeal. The written request should include:

  • Your name, address, phone number, and Medicare number
  • A statement appointing someone as your representative
  • The name, address, and phone number of the representative
  • Your relationship to the representative
  • A statement authorizing the release of your personal and health information to the representative
  • A statement explaining why you are being represented and to what extent

TIP: Your representative can be anyone you trust to act on your behalf, such as a friend, family member, social worker, doctor, or lawyer.

How can I make a strong appeal? Tips for success

You can take steps to ensure your appeal is as strong as possible. Here are some tips to increase your chances of successfully overturning the denial:

  • Read all notices you receive from Medicare carefully and compare them to your Medicare Summary Notice (original Medicare) or Explanation of Benefits (Medicare Advantage) to see what services were or were not covered.
  • Call 1-800-MEDICARE or your plan to see why the service is not being covered. Write down the names of any representatives you speak with, the date and time of your conversation, and what you discussed.
  • Include a letter of support from your health care provider, explaining the medical necessity of your care.
  • Keep a copy of all documents you send and receive.
    • If possible, send the appeal with certified mail or delivery confirmation.
    • Never send the original copies of important documents.

Most importantly, be sure to meet your appeal deadlines—or request a good-cause extension if you cannot.

What if my plan is not responding to my appeal?

If your Medicare plan is being unresponsive to your request for an appeal, you can file a grievance.

To file, send a letter to the plan’s Grievance and Appeals department (you can find the address on the plan’s website or by calling them). Grievances can be filed by phone, in writing, or online. Be sure to file within 60 days of the event that led to the grievance. Once your grievance is filed, the plan must get back to you within 30 days (24 hours for urgent requests). If you have not heard back within this timeframe, call the plan directly or call 1-800-MEDICARE to check the status.

Be persistent with Medicare appeals

If your Medicare appeal is successful, your care will be covered. If it is denied, all hope is not lost—just keep going! Follow the instructions on your appeal denial notice to continue to the next level of appeals.

“Appealing Medicare coverage denials requires lots of patience and persistence,” explains Darren Hotton, NCOA Associate Director of Community Health and Benefits.

But since the majority of coverage denials are overturned at some point during the appeals process, it’s a smart idea to just keep moving forward,” he said.


1. KFF. Over 35 Million Prior Authorization Requests Were Submitted to Medicare Advantage Plans in 2021. February 2, 2023. Found on the internet at,the%20initial%20prior%20authorization%20denial.