Fight the letter

Appealing a Medicare denial: the system expects you to, and folds often

Short answer: appeal. Medicare denials are overturned at remarkable rates, especially the first level and especially in Medicare Advantage, where a large share of appealed prior-authorization denials get reversed. The process is standardized: five levels, each with deadlines, starting with a simple written redetermination request within 120 days. Most people never file, which is precisely why filing works. Here’s the machine, the fast-track version for hospital discharges, and the two paragraphs that make an appeal effective.

By the Medicare Decoder team · Updated August 10, 2026 · 4-minute read · Figures are official 2026 amounts

Key takeaways

Level 1 (redetermination) is a written request within 120 days of the Medicare Summary Notice; no forms, lawyers, or fees required.
A large share of appealed denials, especially Advantage prior-auth denials, are overturned; not appealing is the losing move.
Five escalating levels exist: redetermination, reconsideration, administrative law judge, appeals council, federal court.
Hospital discharge and service-ending disputes use fast appeals through your BFCC-QIO, decided in days, with coverage continuing meanwhile.
Winning appeals pair the denial’s stated reason with a doctor’s letter answering exactly that reason.

Jump to Read the denial correctly The 5 levels Fast appeals Writing one that wins Advantage differences FAQ

Step zero: read the denial correctly

On Original Medicare, "denials" arrive on your quarterly Medicare Summary Notice (or in your Medicare.gov account) as claims marked not covered, with a reason code. A striking share are clerical: wrong billing code, missing documentation, a provider typo. So the first call is to the provider’s billing office ("Medicare denied this; can you verify the coding and resubmit?"), which resolves many "denials" without any appeal at all. What survives that call is worth appealing, and the notice itself lists the appeal deadline and address.

The five levels, in one table

Level	Who decides	Your deadline	Typical timeline
1. Redetermination	The Medicare contractor that processed the claim	120 days from the notice	~60 days
2. Reconsideration	An independent reviewer (QIC)	180 days from the Level 1 decision	~60 days
3. Hearing	Administrative law judge (amount minimums apply)	60 days	Longer; backlogs are real
4. Appeals Council	Medicare Appeals Council review	60 days	Varies
5. Federal court	U.S. District Court (higher amount minimum)	60 days	Litigation timelines

Deadlines run from each decision notice. Most consumer disputes are won or lost at levels 1–2, which cost nothing and require no representation.

The realistic campaign is levels one and two: free, paper-based, and where the overturn rates live. Level 3 exists and works for high-dollar disputes (and advocacy organizations can help there), but the everyday message is simpler: the first appeal is a letter, and the letter often wins.

Fast appeals: when care is ending, not billed

Different track, tighter clock, more power: when a hospital wants to discharge you, or a skilled nursing facility, home health agency, or hospice says covered care is ending, you can demand an immediate review from your regional BFCC-QIO (the quality improvement organization named on the notice they must hand you). Call by the deadline on the notice, typically by midnight of the day before the planned end, and coverage continues while the QIO decides, usually within a day or two. This is the single most underused right in Medicare, and it pairs directly with the maintenance-standard arguments in the therapy article and the home health article: "you’ve plateaued" endings are exactly what fast appeals exist to test.

Writing the appeal that wins

Two paragraphs beat ten pages. Paragraph one: identify the claim (dates, service, claim number from the notice) and state that you’re requesting redetermination. Paragraph two: answer the denial’s stated reason, specifically. Denied as "not medically necessary"? Attach a physician letter saying why it was, in the denial’s own vocabulary. Denied for frequency? The letter explains the clinical need for the interval. Generic outrage loses; targeted rebuttal from the treating doctor wins. Keep copies, send trackable mail (or file online), and calendar the response deadline. If the denial letter cited a coverage rule, quote the rule back with your facts inside it.

On Medicare Advantage, two differences

First, prior authorization moves the fight upstream: request coverage before the service (an "organization determination"), and appeal denials the same way, with expedited 72-hour tracks when health is at risk. Second, the independence arrives at level two automatically: denials your plan upholds get shipped to an outside reviewer without you asking. Given how often appealed Advantage denials are reversed, the operating rule is blunt: a prior-auth "no" is an opening bid, not a verdict. Your doctor’s office files these routinely; ask them to, and ask for the expedited track when timing matters.

Questions people also ask

How do I appeal a Medicare claim denial?

Within 120 days of the Medicare Summary Notice, send a written redetermination request to the address on the notice (or file through your Medicare.gov account): identify the claim, state you’re appealing, and attach a doctor’s letter answering the denial’s stated reason. No fees or lawyers required.

What percentage of Medicare appeals are successful?

Success is common enough that not appealing is the mistake: a substantial share of first-level appeals succeed, and appealed Medicare Advantage prior-authorization denials are overturned at notably high rates. Clerical fixes by the provider resolve many denials before an appeal is even needed.

How do I fight a hospital discharge on Medicare?

Use the fast appeal: call the BFCC-QIO listed on the discharge notice by the deadline printed on it, and coverage continues while the QIO reviews, typically deciding within a day or two. The same immediate-review right applies when skilled nursing, home health, or hospice coverage is ending.

How long does a Medicare appeal take?

Standard redeterminations run about 60 days, as do second-level reconsiderations. Expedited appeals exist when waiting would jeopardize health: 72-hour tracks in Medicare Advantage and fast QIO reviews for facility and service endings.

Should I appeal a Medicare Advantage prior authorization denial?

Almost always. Ask your doctor’s office to file the appeal with supporting clinical notes, request the expedited track when timing matters, and remember an upheld denial automatically goes to an independent outside reviewer at the next level.

Sources for this article

Medicare.govMedicare.gov: the appeals process, notices, and QIO contacts.
Medicare.govCoverage rules: the standards appeals argue against.
CMS.gov2026 premiums and deductibles: the cost-sharing at stake in claim disputes.

Figures checked against these sources in August 2026. We update within weeks when CMS publishes new amounts.

Not sure which path fits you? Get a straight answer.

Start the decoder

Working through this on paper? Our Turning-65 Decision Workbook turns decisions like this one into fill-in pages: your dates, your numbers, the scripts to read from. $24, instant download, updated when the figures change.