If your Medicare Advantage plan denied coverage for an inpatient hospital stay, you can appeal. Federal rules say plans must follow Original Medicare's coverage rules, including the rules for when an inpatient admission is appropriate. You generally have 65 days from the date on the denial notice to ask your plan for a reconsideration.
What happened, exactly?
A plan denial after admission can show up in a few ways:
- A denial letter saying the inpatient stay wasn't medically necessary.
- An Explanation of Benefits (EOB) showing the stay was paid as observation or outpatient care.
- A hospital bill larger than your plan's inpatient copay.
Start by finding the plan's written notice. It should say what was denied, why, and how to appeal. See how to read a Medicare Advantage Explanation of Benefits.
What rules must Medicare Advantage plans follow?
A 2024 federal rule spelled this out. Under 42 CFR 422.101, Medicare Advantage plans must follow the coverage criteria used in Original Medicare. The rule names the payment criteria for inpatient admissions (found at 42 CFR 412.3) as one example. CMS says the rule is meant to make sure people with Medicare Advantage get the same medically necessary care they'd get in Original Medicare.
Plans can use their own internal criteria only when Medicare's criteria aren't fully set, and CMS says those internal criteria must be publicly available.
Why this matters: if your plan's reason for the denial doesn't match Medicare's rules, you can point that out in your appeal.
Who has to review a medical necessity denial?
Under 42 CFR 422.566, if a plan expects to deny a request in whole or in part for medical necessity, a physician or other appropriate health care professional with expertise in that area must review it before the plan issues the decision.
You can ask the plan who reviewed the denial and what criteria they used. See Medicare Advantage denial says "not medically necessary".
What should I check on the denial?
- Dates. Do the admission and discharge dates match?
- Reason. Is it "not medically necessary," "should have been observation," "no prior authorization," or something else?
- Who it's addressed to. Some denials are sent only to the hospital. Ask the hospital whether it got one and whether it plans to appeal.
- Deadline. Find the appeal deadline on the notice.
- What you're being billed. Compare the hospital bill with the EOB.
How do I appeal?
Medicare's appeals booklet says that for Medicare Advantage:
- You or your representative must file a Level 1 appeal (reconsideration) within 65 days from the date on the plan's denial notice.
- The plan has 60 days to decide a payment appeal, 30 days for a service you haven't gotten yet, and 72 hours for a fast appeal.
- If the plan upholds its denial, it automatically sends the case to an Independent Review Entity for Level 2.
Include:
- Your name, address, and plan member information.
- The dates of the hospital stay and what you're appealing.
- Why you think the stay should be covered.
- A letter from the doctor who admitted you, if possible.
For more on deadlines, see Medicare Advantage appeals: deadlines and what to say.
What to ask the doctor's office:
"My Medicare Advantage plan denied [patient name]'s inpatient stay at [hospital] from [date] to [date]. Would the doctor write a short letter explaining why inpatient care was needed? The appeal deadline is [date]."
Sample appeal opening:
"I am asking for a reconsideration of your decision dated [date] denying inpatient coverage for my hospital stay at [hospital] from [date] to [date]. My doctor admitted me as an inpatient because [reason]. Under 42 CFR 422.101, Medicare Advantage plans must follow Original Medicare's coverage criteria for inpatient admissions. Please review the enclosed records and the letter from my doctor."