Your Right to Appeal a Medicare Denial

If Medicare denies payment for a service, test, or item you believe should be covered, you have the legal right to appeal that decision and ask for a fresh review.

The first appeal level for Original Medicare is called a redetermination, which is a new review of your claim by a Medicare Administrative Contractor that was not involved in the initial denial decision.

You generally have 120 days from the date you receive your Medicare Summary Notice, often called an MSN, to file this first-level redetermination request.

The MSN arrives every three months and lists every service Medicare processed during that period, including whether each was approved or denied and the specific deadline by which your appeal must be received.

Understanding the 120-Day Timeline

Medicare assumes you receive your Medicare Summary Notice about five days after the date printed on the notice, and the 120-day appeal clock starts from that presumed receipt date.

If you miss the 120-day window, you can still submit an appeal but you will need to show good cause for the late filing — such as serious illness or a mailing problem — and Medicare decides whether to accept it.

Once you file your redetermination request, Medicare's contractor generally has about 60 days to review the claim and send you a written decision by mail.

If you are unhappy with that outcome, there are additional appeal levels: reconsideration by a Qualified Independent Contractor, a hearing before an administrative law judge, Appeals Council review, and federal court for larger claims.

Key insight: Filing your redetermination request within the 120-day window on your Medicare Summary Notice is the single most important step — missing that deadline makes overturning a denial far more difficult.

How to Use Your Medicare Summary Notice to Appeal

Your Medicare Summary Notice lists each denied service on its own line, and the shaded appeal section on the last page tells you exactly where to send your request and the specific dollar threshold your claim must meet at each appeal level.

To start the appeal, circle the denied service lines on the MSN, write a brief explanation of why you believe Medicare should have paid, sign the form, and mail it to the address shown in the appeal section.

Make copies of everything before you send it — the MSN, your written explanation, and any supporting medical records — so you have a complete file if you need to escalate to higher appeal levels later.

Send your appeal by certified mail or a carrier that provides tracking so you have proof that it arrived within the 120-day window, which can matter if there is ever a dispute about timing.

Strengthening Your Appeal

A strong appeal clearly explains why the service was medically necessary or why Medicare's denial was based on incorrect or incomplete information.

Ask your doctor, therapist, or supplier to provide a letter of medical necessity that connects the denied service to your diagnosis and explains how it meets Medicare's coverage criteria for that type of care.

Include your Medicare number on every page you send, keep a dated log of all phone calls and correspondence, and request a written response so there is a clear paper trail throughout the process.

If your health or ongoing care is at risk because of the denial, ask whether you qualify for an expedited appeal — especially if a hospital, skilled nursing facility, or home health agency is ending services you believe you still need.

Getting Help with the Process

Every state has a State Health Insurance Assistance Program that provides free, one-on-one counseling to Medicare beneficiaries and can help you read your MSN, understand denials, and prepare appeal letters at no charge.

You can also appoint a representative — such as a family member, friend, or advocate — to handle the appeal on your behalf using Medicare's standard representative appointment form, available at Medicare.gov.

By understanding the 120-day timeline, using your Medicare Summary Notice as a guide, and reaching out for help when needed, you significantly improve your chances of overturning an incorrect denial and protecting your coverage.

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