Medicare Advantage Appeal

Medicare Advantage (Part C) plans are private insurers paid to administer Medicare benefits, and most of what they deny runs through prior authorization. KFF reported that MA insurers made about 52.8 million prior-authorization determinations in 2024 and denied roughly 7.7% of them — about 4.1 million denials — yet only 11.5% were appealed. Of the appeals that were filed, 80.7% were overturned in full or in part. An MA denial that goes unappealed is, more often than not, a reversal left on the table.

How appeals work at Medicare Advantage

A Medicare Advantage appeal starts with the plan: a reconsideration, generally requested within 60 days of the denial (42 CFR 422.582). If the plan upholds its denial, the case is automatically forwarded to an independent review entity, and from there the case can climb to a hearing before an Administrative Law Judge at the Office of Medicare Hearings and Appeals, then the Medicare Appeals Council, and finally federal court. The ALJ and federal-court levels carry minimum amount-in-controversy thresholds set each year by CMS — $190 and $1,900, respectively, for 2025. Separately, a 2024 CMS rule (CMS-0057-F) shortened the standard timeline for an initial organization determination to 7 calendar days, with 72 hours for an expedited request.

The Medicare Advantage data

KFF found that in 2024, only 11.5% of denied MA prior-authorization requests were appealed, but 80.7% of those appeals were overturned in full or in part — consistent with the pattern across 2019–2024, where more than eight in ten appeals were overturned.

What Medicare Advantage commonly denies

Prior authorization not on file, or the plan's criteria not documented to its standard.
Medical necessity (CO-50-type) for procedures, imaging, post-acute care, or specialty drugs.
Site-of-care or level-of-care steering — for example, denying inpatient or skilled-nursing days for a lower-cost setting.
An MA coverage rule that is stricter than Medicare's own — a direct target since the 2024 rule.

Is a Medicare Advantage denial worth appealing?

Often worth appealing

Appealing is the high-value default in Medicare Advantage, where most appealed denials are overturned. The strongest lever is the CMS-4201-F rule that took effect in 2024: MA plans must follow Medicare's national and local coverage determinations and traditional-Medicare coverage rules, and may apply their own criteria only when Medicare's are not fully established. A denial that imposes a stricter standard than Medicare itself is directly challengeable. Tie the clinical record to the coverage rule the plan is bound by, and watch the 60-day reconsideration clock.

How to appeal a Medicare Advantage denial

1
File the plan reconsideration in time
The plan-level reconsideration is generally due within 60 days of the denial (42 CFR 422.582) — a shorter window than commercial plans, and a common avoidable loss.
2
Hold the plan to Medicare's own rules
Since 2024, MA plans must follow Medicare's NCDs, LCDs, and coverage conditions. If the denial applies a stricter criterion than Medicare's, say so and cite the Medicare rule it departs from.
3
Map the chart to the cited criterion
Document each element the plan's policy — or the governing Medicare rule — requires, point by point, rather than arguing necessity in general terms.
4
Use the automatic escalation
If the plan upholds the denial, it forwards the case to the independent review entity automatically; from there the appeal can continue to an ALJ hearing, the Appeals Council, and federal court.

Medicare Advantage — frequently asked

How long do I have to appeal a Medicare Advantage denial?

Generally 60 days from the denial to request the plan-level reconsideration (42 CFR 422.582). That is shorter than the 180 days commercial and ACA plans allow, so confirm the date on your notice and file early.

Are Medicare Advantage denials usually overturned?

When they're appealed, most are. KFF found 80.7% of appealed MA prior-authorization denials were overturned in full or in part in 2024. The catch is that only 11.5% of denials were appealed at all.

Can a Medicare Advantage plan deny something traditional Medicare covers?

Since a 2024 CMS rule, MA plans must follow Medicare's national and local coverage determinations and its coverage conditions, and may use their own criteria only where Medicare's aren't fully established. A denial that's stricter than Medicare's own rule is a strong basis for appeal.

Sources

Appeal timeframes and venues are summarized from the federal ERISA/ACA and Medicare Advantage frameworks and vary by plan; payer-specific deadlines and addresses are on your denial notice. Medicare Advantage figures are from KFF's 2024 analysis. This is general information, not legal or coverage advice — confirm the deadline and process on the notice and the plan documents.

When the appeal has to be written, and cited

Upload the denied EOB and Merits returns a complete, citation-verified appeal letter — the clinical argument, the payer's own coverage criteria, and your federal appeal rights — in about a minute.

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