Quick summary: A Medicare Advantage denial is the plan’s first answer, not its last: you have 65 days to appeal, and most people who appeal win. Don’t pay the bill until you know who actually owes it. Free counsellors in every state can help you file. The numbers favour pushing back. KFF’s analysis of 2024 federal data found just 11.5% of denied prior authorisation requests were appealed, though 80.7% of appeals were partially or fully overturned. KFF describes those as requests for care a provider ordered and that was ultimately deemed necessary, but potentially delayed by the extra step of appealing. Timing matters too. Medicare Open Enrolment runs from 15th October 15 to 7th December, so many members are reading plan letters and denial notices at the same time. In my view, the denial notice deserves more attention than any plan brochure, because it shows how a plan behaves when you actually need care.

Most denials come from prior authorisation, the rule that your doctor must get the plan’s approval before certain care. Nearly every Medicare Advantage member is subject to it.

According to Applied Policy’s review of Medicare Advantage prior authorisation, 99% of Medicare Advantage enrolees are in plans requiring prior authorisation for at least some services. The volume is enormous: Healthcare Dive reported nearly 53 million requests in 2024, and nearly 8% were fully or partially denied.

A common misconception is that a denial means the care wasn’t needed. The reality is that some denials are simply wrong. A 2022 audit by the HHS Office of Inspector General found 13% of prior authorisation denials were for services that met Medicare coverage rules, care that Original Medicare would have covered.

Plans also differ widely. In 2024, UnitedHealth denied 12.8% of prior authorisation submissions, while Humana denied 5.8%.

In practice, a denial is a decision you can challenge. The takeaway: treat the letter as the start of a process, not the end of one.

Is a denied claim automatically your bill?

No. A denial means the plan has refused to pay for now. It does not settle who owes the money, and paying early can cost you leverage.

This is where the three-document check earns its place. The denial notice tells you why the plan said no. The Explanation of Benefits shows what the plan paid and what it denied. The provider’s bill shows what someone is asking you to pay. If the three don’t line up, don’t pay yet.

Start with the denial reason. Under the CMS Interoperability and Prior Authorization Final Rule, plans must now give a specific reason for a denied prior authorisation, regardless of how the request was sent. That reason tells you whether the problem is medical necessity, missing paperwork or a network issue. A missing-documentation denial is often fixed by your doctor sending the right records. A medical-necessity denial calls for a formal appeal.

Who caused the denial also matters. If the service was handled by an in-network provider or denied over paperwork you never controlled, you may not owe the full charge. Before writing a check, learn whether a denied claim is actually your financial responsibility. Then ask the provider’s billing office to put the bill on hold while you appeal.

What this means: the bill is the last document to act on, not the first.

How do you appeal a Medicare Advantage denial?

File a written reconsideration with your plan within 65 days of the date on the denial notice, with your doctor’s support. If the plan says no again, the case moves to an independent reviewer automatically.

According to Medicare.gov’s guide to appeals in Medicare health plans, you, your representative or your doctor can file within 65 days. If you miss the deadline, you must give a reason for filing late. Here’s the order I’d follow:

• Mark the date: Count 65 days from the date printed on the notice, not the day it arrived.
• Get your doctor’s letter: A clear explanation of why the care is medically necessary is the strongest evidence you can send.
• Put it in writing: The CMS rules for Medicare Advantage reconsiderations require written standard requests unless your plan accepts verbal ones. Keep copies of everything.
• Ask for speed if your health is at risk: When a physician asks for an expedited reconsideration, the plan must expedite it.
• Know the clock: According to the HHS Office of Medicare Hearings and Appeals, plans usually decide within 30 days for a service and 60 days for a payment.

A common misconception is that a second “no” ends the road. The reality is that a plan that misses its deadline or rules against you must send the appeal to an independent outside reviewer for a Level 2 review.

In practice, the deadline is the only part you can lose by waiting. The takeaway: file first, then gather anything missing.

What will change for Medicare Advantage denials over the next 12 to 24 months?

Denials will get faster, more specific and more public. I expect the biggest shift to be that members can finally compare how plans handle prior authorisation before they enrol.

What most people miss: faster decisions don’t mean fewer denials. Since 2026, plans must decide standard requests within 7 calendar days and urgent ones within 72 hours. A quick “no” still needs an appeal to become a “yes.”

What should you do before you pay the bill?

Run the three-document check, file your appeal before the 65-day deadline and get free help if the case is complicated.

You do not have to do this alone. Every state runs a State Health Insurance Assistance Program (SHIP), and SHIP counsellors are free in all 50 states. For national help, the Medicare Rights Center takes calls at 1-800-333-4114. For repeated denials, hospital stays or bills from several providers, it helps to know what a Medicare patient advocate actually does before you hire one.

Be careful with anyone who promises too much. The Centers for Medicare & Medicaid Services warns against paying anyone who promises to keep medical bills off your credit report or charges an upfront fee to resolve a debt.

In my view, the most expensive mistake is paying a denied bill in the first week. Start today: find the date on your denial notice and write the 65-day deadline on your calendar.

FAQs

• What if my plan misses its appeal deadline? It can’t simply stall. If your plan fails to decide on time, it must send your appeal to an independent reviewer for a Level 2 review. Missing a deadline never counts as a final “no.”
• What happens at Level 2? An Independent Review Entity, which is not part of your plan, reviews the case again. If you still disagree after that, higher levels of appeal are available, including a hearing before a judge.
• What if the hospital wants to discharge me too soon? You have a separate, faster right. If you disagree with a decision to discharge you or stop services, you can request an immediate review by a Quality Improvement Organization. Ask hospital staff for the notice that explains how.
• Is an Explanation of Benefits a bill? No. It shows what your plan paid and denied. Only pay amounts on an actual bill from your provider, and only after checking them against the Explanation of Benefits and any denial notice.
• Can I switch plans if mine keeps denying care? Yes. During Open Enrolment, from 15th October to 7th December, you can move to a different Medicare Advantage plan or return to Original Medicare. Compare each plan’s prior authorisation rules and your doctors’ networks before you switch.

Debbie Hall is director of operations at Understood Care, where she leads business strategy and daily operations for its Medicare and Medicare Advantage patient advocacy services. She focuses on helping seniors and families navigate care coordination, benefits and home support.