Your healthcare provider may need to submit a prior authorization form to Medicare before providing medical services. Sometimes prior authorization is necessary for a prescription drug to be filled. In some cases, Medicare coverage is only applied if there is pre-approval for the procedure.

Keep reading to learn more about Medicare prior authorization requirements. We’ll review instances when prior approval is necessary, which plans require approvals, and how to file an appeal if you disagree with a decision. Then, we’ll answer some frequently asked questions.

What is Prior Authorization in Medicare?

Prior authorization is sometimes necessary to prove medical necessity for a specific healthcare service, supply, or medication. Regarding Medicare Part C or Medicare Part D plans, health coverage is plan specific. You’ll want to talk to your health insurance company about your coverage.

Medicare Part A, which includes inpatient care, rarely requests prior approval. Suppose there is a request under Part A. In that case, it’s for Durable Medical Equipment in the hospital or prosthetics. You can get these forms from your doctor or hospital, then send them to Medicare.

Medicare Part B, which includes outpatient care, sometimes requests prior approval. A doctor may submit a Part B drug prior authorization request form for medications in an outpatient setting. Once approved, coverage begins. The goal of prior authorization is to prioritize medical necessity.

What is the prior authorization process?

Prior authorization is pre-approval from an insurance company for health care, medications, or medical supplies. Prior approval helps health plans control costs by reviewing expensive or dangerous treatments to ensure medical necessity.

Generally, you won’t submit the prior authorization forms. Instead, the doctor’s office where you receive care will submit the documents to the insurance company. Enrollees will get a call from the doctor’s office to notify them of the decision made by the insurance plan.

Do Medicare Advantage plans require prior authorization?

Medicare beneficiaries with a Part C Medicare Advantage Plan may need prior authorization for certain medical services. Instances you may require prior approval include needing to see a specialist, getting out-of-network care, Durable Medical Equipment, Part B meds, and more.

Most Part C plans requires prior approval for at least some services. Each policy is different, but for the most part, if Medicare wouldn’t approve the request, the Part C plan won’t approve it either. Contact your insurance company to verify your specific plan details or download the forms online.

Do I need prior authorization with a Medicare Part D Prescription Drug Plan?

Part D beneficiaries may need prior approval for certain medications. Each policy is slightly different, and the plans have different rules. You’ll need to confirm coverage with your health plan.

You may be able to download the Part D plan forms off the internet. If possible, you can print and take the forms with you to the doctor’s office for your healthcare provider to assist you in completing the forms.

You can also call your healthcare plan and request the forms be mailed. Generally, your member services phone number is on the back of your insurance plan card.

Your formulary, or list of covered drugs, will have information on step therapy, prior authorization, and quantity limits. To submit authorization, you can print out and complete a Medicare Part D prior authorization form, also known as a Coverage Determination Request Form. Once completed, send it to the office of your plan. You may need your doctor’s assistance filling out the form, and they may need to sign the document.

Do I need prior approval with a Medigap plan?

Medicare Supplemental insurance is different because it’s secondary to Medicare. Since Medicare is primary, the Medigap insurance company must also approve the claim if Medicare approves the claim.

No referrals are necessary with Medigap insurance, and you can see any doctor in the United States who accepts Medicare.

What is the appeal process for wrongful prior authorization denials?

Medicare beneficiaries have the right to appeal plan decisions. You may also submit new documentation. It’s a legal requirement for the insurance company to disclose why they denied your request.

If the reason for denial was “no pre-authorization,” contact the plan and ask them to back-date prior authorization. You can resubmit the claim with a note that includes the new authorization if the plan agrees to back-date. If the plan doesn’t agree to back-date, file an appeal.


Is there an electronic prior authorization form?

Yes. Doctors often communicate information between themselves and the insurance company via an Electronic Prior Authorization (EPA).

Do I need prior authorization for an MRI?

Part B will cover your MRI if you have Original Medicare, which doesn’t require prior approval. However, Medicare Advantage plans may request prior authorization for this type of testing.

What are the benefits of prior authorization?

While getting prior approval may seem like a hassle, it does help protect insurance companies from overspending on unnecessary medical services.

Prescription prior authorization can help you by preventing potentially dangerous medication combinations. Also, it enables you to avoid treatments or medications that may be addictive or unnecessary.

Does Medicare Part B require prior authorization?

The answer is sometimes. Medicare wants to prioritize the essential services first, so your doctor may want to ensure that Medicare will cover your services or medication before dispensing either.

How long does a prior authorization last?

As of the CMS 2024 Final Rule, CMS requires that the PA remains as long as it is medically necessary and according to the following:

  • To ensure continuity of care
  • Considering the patient’s medical history
  • The applicable coverage criteria
  • The treating provider’s recommendations

How to Receive Help with Prior Authorization Requests

Our insurance agents can help you with many things, which include prior authorization requests, appeals, enrollment, and more. We strive to make Medicare easier for our clients.

Call us today to start working with an agent licensed in your state. Or fill out an online rate form to receive plan quotes in your area now.

Written By:
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Lindsay Malzone, Lindsay Malzone is the Medicare editor for She's been contributing to many well-known publications since 2017. Her passion is educating Medicare beneficiaries on all their supplemental Medicare options so they can make an informed decision on their healthcare coverage.
Reviewed By:
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Rodolfo Marrero, Rodolfo Marrero is one of the co-founders at He has been helping consumers find the right coverage since the site was founded in 2013. Rodolfo is a licensed insurance agent that works hand-in-hand with the team to ensure the accuracy of the content.