Priya Desai, 68, was standing at her pharmacy counter reading a denial letter on her tablet when she realized her Medicare Advantage plan had refused to cover the knee MRI her orthopedist had ordered three weeks earlier. The denial cited “not medically necessary at this time.” The cash price was $1,400. The reason most beneficiaries in her position would have paid the $1,400 is the same reason she did not: most Medicare Advantage prior authorization denials are never appealed, even though the majority of appeals win.
Medicare Advantage plans require prior authorization for many services that Original Medicare covers without one. The plan reviews the request, applies its own coverage criteria, and approves or denies. A denial does not mean the service is not covered. It means the plan does not believe the request meets its internal medical necessity rules, and the patient has the right to challenge that decision through a defined appeal process.
Why prior authorization denials happen
The most common reasons for denial are missing or incomplete documentation from the ordering provider, the plan’s belief that a less expensive alternative should be tried first (“step therapy”), the service falling outside the plan’s network, or the plan applying narrower medical necessity criteria than Original Medicare uses. The OIG report cited above found that in many denied cases, the documentation actually supported coverage but was misread or insufficiently reviewed by the plan’s clinical staff.
KFF reported that roughly 10 percent of Medicare Advantage denials are appealed by beneficiaries. Of those that are appealed, the majority are overturned in the beneficiary’s favor at one of the appeal levels. The math is unforgiving: most people pay or skip the service, and most of those who fight win.
The five-level appeal process
Medicare Advantage appeals run through five levels, each handled by a different body:
1. Redetermination by the plan itself. The patient or provider files a written request within 60 days of the denial. The plan must respond within 30 days for pre-service requests or 60 days for payment disputes. 2. Reconsideration by an independent review entity (IRE) contracted by CMS. Filed within 60 days of the redetermination denial. The IRE is independent of the plan and reviews the case fresh. 3. Administrative Law Judge (ALJ) hearing. Available when the disputed amount meets a minimum threshold (which adjusts annually). The ALJ holds a hearing, often by phone or video, and issues a binding decision. 4. Medicare Appeals Council review. A final administrative appeal, available within 60 days of the ALJ decision. 5. Federal District Court review. Available for cases meeting the minimum amount threshold, after all administrative appeals are exhausted.
Most beneficiaries who win do so at level 1 or level 2. The higher levels are rare and usually involve large or repeat-denied claims.
Expedited appeals when delay is dangerous
Standard pre-service appeals take up to 30 days. Expedited appeals must be decided within 72 hours, and the patient or provider can request expedited review whenever delay would put the patient’s health at serious risk. Common examples include cancer treatment delays, post-surgical rehabilitation cutoffs, and denied medications for chronic conditions where stopping is dangerous. The treating physician usually writes the expedited request, citing the specific health risk of waiting.
If a plan denies an expedited request and forces the standard timeline, that decision can also be appealed. CMS scrutinizes plans that misuse the expedited process to push appeals out.
What the new CMS rules change
In 2024, CMS finalized rules that took effect in 2026 requiring Medicare Advantage plans to align their prior authorization criteria more closely with Original Medicare’s coverage rules, respond to standard prior auth requests within 7 days (down from 14), and respond to urgent requests within 72 hours. Plans must also publicly report their prior authorization denial rates and approval timing.
The rules do not eliminate prior authorization. They tighten the deadlines and reduce the gap between MA coverage and Original Medicare coverage. Beneficiaries who were on the wrong end of a denial under the old rules should refile if the same service is needed again, since the criteria have changed.
If you are weighing Medicare Advantage against Original Medicare for the next enrollment period, the differences in coverage and out-of-pocket structure include prior authorization rules. Original Medicare requires far fewer pre-approvals, and a beneficiary frustrated by repeated denials can use that as a factor in the next plan choice.
Compare Medicare plans before the next enrollment window
Prior authorization rules vary widely between Medicare Advantage plans. See plans available in your area and how each handles common services.
Get Medicare Plan QuotesFrequently asked questions
How long do I have to file an appeal after a denial?
You have 60 days from the date of the written denial notice to file the level 1 redetermination request with the plan. Each subsequent level also has a 60-day filing window from the prior decision date. Missing the window usually ends the appeal.
Can my doctor file the appeal for me?
Yes. The treating provider can file on the beneficiary’s behalf with written consent. Provider-filed appeals tend to include stronger clinical documentation and are often filed faster than patient-filed appeals.
What happens if I pay for the service while the appeal is pending?
You can still appeal and seek reimbursement. The level 1 redetermination request asks the plan to reconsider, and if approved, the plan is required to reimburse the amount it would have paid had the service been authorized. Save every receipt and the original denial.
Are denials more common in some Medicare Advantage plans than others?
Yes. CMS now publishes prior authorization denial rates by plan. Some plans deny well above the national average and have higher overturn rates on appeal, which suggests their criteria are tighter than the rules require. Comparing denial rates is part of comparing plans during enrollment.
Does the appeal cost anything to file?
No. Levels 1 and 2 are free to file. Higher levels (ALJ, Council, federal court) involve administrative requirements but no filing fees. Beneficiaries can also use Medicare’s free counseling program (SHIP) for help at any level.
