If you're enrolled in a Medicare Advantage plan, you've almost certainly encountered the phrase 'prior authorization' — and possibly the frustration that comes with it. Prior authorization, or prior auth, is the process by which your Medicare Advantage insurer must approve certain medical services, procedures, medications, or equipment before you receive them. Without that approval, the plan may refuse to pay. A bipartisan legislative effort called the WISeR Act — short for the Improving Seniors' Timely Access to Care Act's successor proposal — aimed to put strict time limits on how long insurers could take to respond to these requests, particularly for urgent medical situations. That effort has now died in the Senate, and for the roughly 33 million Americans enrolled in Medicare Advantage plans in 2025, the status quo remains firmly in place.
To understand why this matters, it helps to understand just how common prior authorization denials and delays have become in Medicare Advantage. Unlike Original Medicare (Parts A and B), which generally pays for any medically necessary service a doctor orders, Medicare Advantage plans — which are run by private insurers like UnitedHealthcare, Humana, Aetna, and Blue Cross Blue Shield affiliates — are permitted to require prior authorization for a wide range of services. That can include everything from MRI scans and physical therapy to skilled nursing facility stays and certain cancer treatments. The insurer has the legal authority to say 'not yet' or even 'no' before your doctor can proceed.
According to CMS.gov data from its Medicare Advantage and Part D Contract and Enrollment data releases, there were 7,543 Medicare Advantage plans available nationwide in 2025 across all plan types, including HMOs, PPOs, and Special Needs Plans. Each of those plans sets its own prior authorization requirements, meaning the rules can vary dramatically from one insurer to another — and even from one county to another within the same state. A beneficiary in Miami enrolled in a particular HMO plan may face entirely different prior auth hurdles than someone in Tampa enrolled in what appears to be the same insurer's product.
The WISeR Act — which built on the earlier Improving Seniors' Timely Access to Care Act that passed the House in 2022 but never became law — would have required Medicare Advantage plans to make prior authorization decisions within 24 hours for urgent requests and within 72 hours for standard requests. It also would have mandated that plans use electronic prior authorization systems to reduce paperwork delays, required greater transparency about which services require prior auth, and limited the ability of insurers to change prior authorization requirements mid-year in ways that disrupt ongoing care. These were not radical proposals. They were largely administrative guardrails designed to prevent the most egregious delays — the kind where a patient is waiting in a hospital bed while an insurer takes days or weeks to approve a transfer to a rehabilitation facility.
The Senate's failure to advance the legislation means none of those protections will become federal law in the near term. Insurers retain the ability to take as long as current regulations allow — which, under existing CMS rules, means up to 14 calendar days for standard prior authorization requests and 72 hours for expedited requests when a doctor certifies that waiting could seriously jeopardize the patient's health. Critics argue that 14 days is far too long for many medical situations, and that the 72-hour expedited window is often not invoked because physicians face administrative burdens in certifying urgency. The legislative failure leaves those timelines unchanged.
It's worth noting that CMS did implement some prior authorization reforms through its own regulatory authority in recent years. A 2023 CMS final rule required Medicare Advantage plans to apply the same coverage criteria as Original Medicare when making prior authorization decisions for services covered under both programs — meaning plans can no longer use stricter internal criteria to deny care that Original Medicare would cover. CMS also finalized rules in 2024 requiring plans to implement electronic prior authorization systems by 2027 and to provide specific clinical reasons for any denial. These are meaningful improvements, but they do not address the speed problem that the WISeR Act was specifically designed to fix. Regulatory rules and legislative mandates are different tools, and the death of WISeR in the Senate leaves a real gap.
For beneficiaries currently dealing with a prior authorization denial or delay, the most important thing to know is that you have rights — and exercising them can work. Every Medicare Advantage plan is required to have an internal appeals process. If your plan denies a prior authorization request, you can file a Level 1 Appeal (also called a plan redetermination) within 60 days of the denial notice. If that appeal is denied, you can escalate to a Level 2 Appeal before an independent review organization. If you need a faster decision — for example, if you're in the hospital and waiting for approval to transfer to a skilled nursing facility — you can request an expedited appeal, which requires the plan to respond within 72 hours. Studies and CMS data have consistently shown that a substantial percentage of Medicare Advantage denials that are appealed are ultimately reversed, meaning the plan ends up approving the service. The appeals process is not just bureaucratic theater — it can genuinely change outcomes.
Your State Health Insurance Assistance Program, known as SHIP, offers free, unbiased counseling to Medicare beneficiaries and can help you navigate a prior authorization dispute. SHIP counselors are not insurance agents and have no financial interest in steering you toward any particular plan. They can help you understand your denial notice, draft an appeal letter, and identify whether your situation qualifies for an expedited review. To find your local SHIP office, visit shiphelp.org or call 1-800-MEDICARE (1-800-633-4227). This is a genuinely useful resource that many beneficiaries don't know exists.
If you're frustrated with your current Medicare Advantage plan's prior authorization practices, you do have the ability to switch plans — but only during specific enrollment windows. The Annual Enrollment Period runs from October 15 through December 7 each year, and any changes you make take effect January 1. The Medicare Advantage Open Enrollment Period runs from January 1 through March 31, during which you can switch from one Medicare Advantage plan to another, or drop Medicare Advantage entirely and return to Original Medicare (though returning to Original Medicare mid-year may affect your ability to get a Medigap supplement policy without medical underwriting in most states). Outside of these windows, you generally cannot switch plans unless you qualify for a Special Enrollment Period triggered by a qualifying event such as moving out of your plan's service area, losing other coverage, or qualifying for a low-income subsidy.
One alternative worth considering if prior authorization is a persistent concern: Original Medicare combined with a Medigap (Medicare Supplement) policy. Original Medicare does not use prior authorization for medically necessary services. If your doctor orders a service that Medicare covers, it's covered — no insurer approval required. A Medigap policy then covers most or all of your out-of-pocket costs, including deductibles and coinsurance. The tradeoff is cost: Medigap premiums can range from roughly $100 to $300 or more per month depending on your age, location, plan letter, and health status, and in most states, insurers can use medical underwriting if you're past your initial enrollment window. However, if you live in one of the 13 states with a birthday rule — California, Idaho, Illinois, Kentucky, Louisiana, Maine, Maryland, Missouri, Nevada, New Jersey, New York, Oklahoma, or Oregon — you have a 30-day window each year around your birthday to switch Medigap plans without medical underwriting, which can make this option more accessible.
The broader political picture matters here too. The failure of the WISeR Act is not necessarily the end of prior authorization reform efforts — it's a setback in a longer legislative fight. Advocacy organizations including AARP have made prior authorization reform a top legislative priority, and there is genuine bipartisan frustration with the current system among members of Congress whose constituents have experienced care delays. The issue is likely to resurface in future legislative sessions. In the meantime, CMS continues to have regulatory authority to tighten prior authorization rules without congressional action, and the agency has signaled ongoing interest in doing so. Beneficiaries who want to support reform efforts can contact their senators and representatives directly — constituent pressure has historically been one of the most effective tools in shaping Medicare policy.
Data Snapshot: According to CMS.gov Medicare Advantage plan data for 2025, the average Medicare Advantage plan enrollee had access to 43 plan options in their county, up from 39 in 2023. CMS's own analysis of Medicare Advantage organization determinations found that plans issued approximately 35 million prior authorization determinations in a recent reporting year, with denial rates varying significantly by plan and service type — underscoring just how central prior authorization has become to the day-to-day experience of Medicare Advantage enrollment.
The bottom line for beneficiaries is this: the WISeR Act's failure means the prior authorization system in Medicare Advantage will continue operating largely as it has, with the same timelines and the same potential for delays. That doesn't mean you're powerless. Know your appeal rights, use your SHIP counselor, document every interaction with your insurer, and during the next enrollment period, compare plans not just on premiums and drug coverage but on their prior authorization track records — CMS publishes star ratings that include measures of plan responsiveness and member experience, and those ratings are available at medicare.gov/plan-compare. A plan with a 4- or 5-star rating has generally demonstrated better performance on these measures than a 2- or 3-star plan, and that difference can matter enormously when you need care quickly.