People are leaving Medicare Advantage plans because of rising out-of-pocket costs, shrinking provider networks, and frustration with prior authorization requirements that delay or block care. A 2024 Health Affairs study found that 19% of those who left a Medicare Advantage plan were dissatisfied with costs, while 9.2% reported trouble getting needed medical care. These aren’t abstract policy complaints. They reflect real barriers that push people back toward Original Medicare or into different plans entirely.
Cost Dissatisfaction Is the Top Reason
Many people sign up for Medicare Advantage because of $0 premium plans and extra benefits like dental and vision coverage. But premiums don’t tell the whole story. When you actually use care, especially for a serious illness, the out-of-pocket costs can add up fast. The average in-network out-of-pocket maximum jumped from $4,882 in 2024 to $5,320 in 2025. For PPO plans that include out-of-network care, the average limit rose from $8,707 to $9,547. The legal ceiling for 2025 is $9,350 for in-network services alone, and $14,000 when out-of-network costs are included.
These maximums represent worst-case scenarios, but people with cancer, heart disease, or other conditions requiring extensive treatment can hit them. By comparison, someone on Original Medicare with a Medigap supplement plan typically has more predictable costs. Nearly one in five people who left their Medicare Advantage plan cited cost dissatisfaction as a reason.
Hospitals Are Dropping Medicare Advantage Contracts
One of the most disruptive reasons people leave is that their doctors or hospitals stop accepting their plan. Becker’s Hospital Review tracked 32 health systems that dropped or limited Medicare Advantage contracts heading into 2025. The list includes major names: Vanderbilt Health ended its contract with Blue Cross Blue Shield of Tennessee’s Medicare Advantage plans. Ohio State University’s Wexner Medical Center went out of network with Anthem Medicare Advantage. CommonSpirit hospitals in Colorado split from Humana. Systems in Minnesota, South Dakota, Indiana, Maine, Michigan, Kansas, and New York all made similar moves.
The pattern is striking, and the reasons hospitals give are consistent: excessive prior authorization denial rates and slow payments from insurers. When a hospital decides that a Medicare Advantage insurer isn’t paying fairly or is creating too much administrative burden, it terminates the contract. The patient then faces a choice: find a new doctor within the plan’s remaining network, switch to a different Medicare Advantage plan that still includes their provider, or leave Medicare Advantage altogether.
Prior Authorization Creates Barriers to Care
Prior authorization, the process where an insurer must approve a treatment before you receive it, is far more common in Medicare Advantage than in Original Medicare. In 2024, Medicare Advantage insurers processed nearly 53 million prior authorization requests, averaging 1.7 requests per enrollee. Traditional Medicare, by contrast, generated roughly 625,000 prior authorization requests that same year, a rate of about 0.02 per enrollee. Virtually all Medicare Advantage enrollees (99%) are in plans that require prior authorization for at least some services, particularly expensive ones like inpatient hospital stays, skilled nursing facility care, and chemotherapy.
The denial numbers matter too. In 2024, insurers fully or partially denied 7.7% of all prior authorization requests, up from 6.4% in 2023. That translated to 4.1 million denied requests. Only 11.5% of those denials were appealed, but when people did appeal, 80.7% of appeals were partially or fully overturned. That reversal rate suggests many initial denials were not clinically justified, which is exactly the complaint patients and providers have been raising for years.
For someone dealing with a new diagnosis or an urgent health need, a prior authorization denial can mean delayed surgery, postponed imaging, or gaps in medication. Among beneficiaries who left their Medicare Advantage plan, 9.2% reported trouble getting needed medical care, compared to 5.5% of those who stayed.
Specialty Care Access Is a Recurring Problem
General practitioner access is one thing, but specialty care is where Medicare Advantage networks often feel thinnest. About 7.3% of people who left their plan were dissatisfied with specialty care specifically, and 6% were unhappy with quality of care overall. These numbers may sound modest, but they represent the people who actually switched. Many more may be dissatisfied but stay because switching feels complicated or risky.
Narrow networks are a design feature of Medicare Advantage, not a bug. Insurers negotiate lower rates with a smaller set of providers, which is how they fund the extra benefits that attract enrollees. But when you need a particular specialist, especially in a rural area or for a rare condition, a narrow network can mean long drives, long waits, or settling for whoever is available.
New Federal Rules Are Tightening Oversight
CMS finalized several regulatory changes for 2025 that affect how Medicare Advantage plans operate. One significant shift targets marketing practices. Agents and brokers now receive a fixed compensation amount regardless of which plan they enroll someone in, closing loopholes that previously let insurers pay higher commissions to steer people toward specific plans. Third-party marketing organizations can no longer share your personal data with other marketers without your explicit, individual written consent for each organization.
On the care delivery side, CMS added new network adequacy standards for outpatient behavioral health, requiring plans to include verified behavioral health providers in their networks. Plans must confirm that listed providers actually see at least 20 patients within a 12-month period, addressing the longstanding “ghost network” problem where directories list providers who aren’t actually available.
These rules don’t directly cause people to leave, but they reflect the kinds of problems that have been driving dissatisfaction: aggressive marketing that enrolls people in unsuitable plans, and networks that look adequate on paper but fall short in practice.
Switching Back Isn’t Always Simple
If you want to leave Medicare Advantage for Original Medicare, timing matters. The main window is the annual Open Enrollment Period from October 15 through December 7, with coverage starting January 1. There’s also the Medicare Advantage Open Enrollment Period from January 1 through March 31, available only to current Medicare Advantage enrollees, where you can drop your plan and return to Original Medicare with coverage starting the first of the following month.
The bigger obstacle is Medigap coverage. Medigap (Medicare supplement) policies cover the cost-sharing gaps in Original Medicare, like the 20% coinsurance on outpatient services. You have a guaranteed right to buy any Medigap policy during your initial six-month open enrollment window when you first enroll in Medicare Part B. But if you’ve been in a Medicare Advantage plan for years and then switch back, that window has closed. Outside of it, insurance companies in most states can deny you a Medigap policy based on your health history or charge higher premiums. Some states offer additional protections, so your options depend on where you live.
This Medigap barrier is one of the most consequential and least understood aspects of Medicare Advantage. It can effectively lock people into the Medicare Advantage system even when they’re unhappy, because returning to Original Medicare without a supplement policy exposes them to potentially unlimited cost-sharing on Part B services.
The Revolving Door Pattern
Research from the University of Michigan found that about 3% of people on Original Medicare switch to a Medicare Advantage plan each year. But among those who had recently left Medicare Advantage for Original Medicare, the rate of switching back was more than double: 6.5% among those who had been back on traditional Medicare for one to three years, and 9% among those who had switched just the year before. This “revolving door” pattern suggests that many people who leave Medicare Advantage find Original Medicare doesn’t fully meet their needs either, particularly if they can’t secure affordable Medigap coverage or miss the supplemental benefits like dental and vision that Medicare Advantage provided.
The decision to leave a Medicare Advantage plan is rarely straightforward. It involves weighing provider access, cost predictability, benefit extras, and the risk of losing future Medigap eligibility. For a growing number of people, the frustrations with denied care, vanishing networks, and rising costs are tipping that balance.