Medicare Prior Authorization: Why Delays Cost Seniors Care

If you've ever had a doctor recommend a procedure, a specialist visit, or a medication — only to be told your Medicare Advantage plan needs to 'review' it first — you've encountered prior authorization. It sounds like a routine administrative step, but for hundreds of thousands of Medicare beneficiaries each year, it becomes a wall between them and the care their doctors say they need. Congressional scrutiny of the Centers for Medicare & Medicaid Services (CMS) has intensified around this issue, with lawmakers arguing that CMS has failed to adequately police how Medicare Advantage insurers use prior authorization to delay or deny care. The criticism is pointed: that the agency responsible for protecting Medicare beneficiaries has allowed private insurance companies to profit by blocking access to services that traditional Medicare would have covered without question.

Prior authorization is a requirement that your Medicare Advantage plan approve certain medical services, procedures, or prescription drugs before you receive them. The insurer reviews the request — usually submitted by your doctor — and decides whether the service is 'medically necessary' according to the plan's own criteria. If approved, you can proceed. If denied, you're left scrambling. The problem is that Medicare Advantage plans have significant financial incentive to deny or delay these requests: every service they don't pay for improves their bottom line. Critics, including members of Congress, argue this creates a structural conflict of interest that CMS has not adequately addressed through oversight or enforcement.

According to CMS.gov data, Medicare Advantage enrollment reached approximately 33.8 million beneficiaries in 2024, representing more than half of all Medicare enrollees. With that many people in private Medicare plans, the scale of prior authorization activity is enormous. A 2022 report from the HHS Office of Inspector General found that Medicare Advantage plans denied 13% of prior authorization requests that met Medicare coverage rules — meaning those services should have been approved. The same report found that when beneficiaries appealed those denials, plans overturned 75% of them. That's a striking number: three out of four appealed denials were reversed, suggesting the initial denials were often unjustified. Yet most beneficiaries never appeal, either because they don't know they can or because the process feels overwhelming.

The legislative response has been building for years. The Improving Seniors' Timely Access to Care Act, which became law in 2022, was designed to reform how Medicare Advantage plans use prior authorization. The law required CMS to establish electronic prior authorization systems, mandate faster response times, and increase transparency about how plans use these tools. Specifically, plans are now required to respond to standard prior authorization requests within 7 calendar days and urgent or expedited requests within 72 hours. For context, before this law, some plans were taking weeks to respond to standard requests — weeks during which a patient might be in pain, losing function, or facing a worsening condition. The law also required plans to report prior authorization data publicly, so beneficiaries and researchers can see how often plans deny requests and in which clinical categories.

But passing a law and enforcing it are two different things. Congressional critics have argued that CMS has been slow to implement the full requirements of the 2022 law and has not penalized plans aggressively enough for violations. The 'Golden Fleece' designation — a congressional rebuke historically given to government programs seen as wasting taxpayer money or failing the public — reflects frustration that CMS is collecting billions in payments to oversee Medicare Advantage while beneficiaries continue to face improper denials. The argument is that CMS has the authority to audit plans, impose civil monetary penalties, and even terminate contracts with plans that repeatedly violate Medicare rules — but has used those tools sparingly. Between 2015 and 2022, CMS terminated fewer than a handful of Medicare Advantage contracts for cause, despite widespread documented problems.

For beneficiaries, understanding how prior authorization works in your specific plan is essential. Not all Medicare Advantage plans use prior authorization the same way. Some plans require it for a wide range of services — inpatient hospital stays, skilled nursing facility care, home health services, durable medical equipment, certain imaging like MRIs and CT scans, and specialty drugs. Others use it more selectively. When you're comparing Medicare Advantage plans during the Annual Enrollment Period (October 15 through December 7 each year), you can look up each plan's prior authorization requirements on Medicare.gov's Plan Finder tool. Plans are required to publish their prior authorization policies, and you can ask the plan directly for a list of services that require approval before you enroll.

If you're already in a Medicare Advantage plan and your doctor submits a prior authorization request that gets denied, here is exactly what you should do. First, ask your doctor's office for the specific reason for the denial in writing — plans are required to provide this. Second, ask your doctor whether they can submit additional clinical documentation supporting medical necessity; many denials are overturned at this stage with more complete records. Third, file a formal appeal with the plan. You have the right to request a 'reconsideration' by the plan, and if the plan upholds the denial, the case automatically goes to an independent review organization called a Qualified Independent Contractor (QIC) — a third party with no financial relationship to your insurer. If your situation is urgent, request an expedited appeal, which requires a decision within 72 hours. You can also contact your State Health Insurance Assistance Program (SHIP) counselor for free help navigating the appeals process — find your local SHIP at shiphelp.org.

One area where prior authorization problems are particularly acute is post-acute care: skilled nursing facilities, inpatient rehabilitation, and home health services following a hospitalization. These are exactly the services seniors need most after a serious illness or surgery, and they are among the most frequently denied categories in Medicare Advantage. A 2023 Senate Finance Committee investigation found that the three largest Medicare Advantage insurers — UnitedHealthcare, Humana, and CVS Health/Aetna — denied post-acute care requests at rates significantly higher than the Medicare fee-for-service baseline. For a beneficiary recovering from a hip replacement or a stroke, a denial of skilled nursing facility care isn't an inconvenience — it can mean going home without adequate rehabilitation, increasing the risk of falls, readmission, or permanent disability.

It's worth understanding how prior authorization in Medicare Advantage differs from traditional Medicare. If you're enrolled in original Medicare (Parts A and B), prior authorization is rarely required. Your doctor orders a service, you receive it, and Medicare pays its share. There are a small number of services — certain outpatient imaging and non-emergency ambulance transport — where Medicare has piloted prior authorization programs, but these are narrow exceptions. The broad, plan-wide prior authorization systems that characterize Medicare Advantage simply don't exist in traditional Medicare. This is one of the most important trade-offs to understand when choosing between Medicare Advantage and original Medicare with a Medigap supplement plan. Medicare Advantage plans often have lower or zero monthly premiums and may include extra benefits like dental and vision, but they also come with prior authorization requirements, network restrictions, and cost-sharing structures that can create barriers to care.

Medigap plans — also called Medicare Supplement plans — work alongside original Medicare and generally do not involve prior authorization. If you have original Medicare plus a Medigap Plan G, for example, Medicare approves the service and Medigap pays most or all of your cost-sharing. In 2025, the average monthly premium for a Medigap Plan G for a 65-year-old non-smoking woman ranged from roughly $100 to $200 per month depending on the state and insurer, according to industry data. That's a real monthly cost compared to a $0-premium Medicare Advantage plan, but for beneficiaries who use significant healthcare services, the predictability and access that comes with original Medicare plus Medigap may be worth the premium. This is a personal calculation that depends on your health status, your doctors, your finances, and your tolerance for administrative complexity.

If you're in a state with a birthday rule, you have an additional option worth knowing about. In California, Idaho, Illinois, Kentucky, Louisiana, Maine, Maryland, Missouri, Nevada, New Jersey, New York, Oklahoma, and Oregon, you have a 30-day window around your birthday each year to switch from one Medigap plan to another of equal or lesser benefit without medical underwriting — meaning insurers cannot deny you or charge you more based on your health history. This can be a valuable opportunity to shop for a lower premium on the same coverage, or to switch to a plan that better fits your current needs.

The broader policy debate about prior authorization is not going away. CMS has proposed additional rules requiring Medicare Advantage plans to use prior authorization criteria that are consistent with traditional Medicare coverage standards — meaning plans could not deny something that Medicare would cover. If finalized and enforced, this rule could significantly reduce improper denials. Advocacy organizations including AARP have been vocal in pushing for stronger enforcement, arguing that the current system allows insurers to profit from denials while CMS looks the other way. Whether CMS acts more aggressively under current leadership remains to be seen, but the congressional pressure and public attention on this issue are at historic levels.

For now, the most important thing you can do as a Medicare beneficiary is know your rights. If you're in Medicare Advantage, understand which services require prior authorization under your plan. If a request is denied, appeal — the data shows appeals frequently succeed. If you're choosing between Medicare Advantage and original Medicare, factor in prior authorization as a real cost of the Medicare Advantage model, not just a paperwork formality. And if you need help, your SHIP counselor, your State Insurance Commissioner's office, or Medicare.gov's 24-hour helpline at 1-800-MEDICARE (1-800-633-4227) can provide guidance specific to your situation at no cost.