Buyer’s remorse about your Medicare Advantage plan? You have a few weeks to fix it.

Millions of Americans change Medicare Advantage plans each year or transfer to original Medicare during the open enrollment period that ends on March 31.

However, you cannot jump from a traditional Medicare plan to a Medicare Advantage one. You will have to wait for the fall registration period for that change. New coverage will take effect on the first day of the month when the change request is received.

People are often motivated to move plans after finding out that the doctor or hospital they want to use is no longer in the Medicare Advantage plan’s network.

“If you find out that the Medicare Advantage plan you chose last year isn’t your best option after you started using it in January, do something about it now,” Kimberly Lankford, a Medicare expert and author of “Medicare 101,” told Yahoo Finance.

“You may also find that some of your medications are not on the plan’s formulary – a big surprise at the pharmacy if your prescription is dropped. Not only will you have higher out-of-pocket costs, but you won’t be covered for the $2,100 out-of-pocket for drugs not included in your plan.

Importantly, your health needs may have changed since you last reviewed your plan. You may be prescribed new medications or develop a new medical condition, and you may have different coverage needs than you had when you bought the policy in the fall, he added.

There may be many jumping ship for many reasons this year. Many seniors are waking up to Medicare Advantage plans with cut benefits and high out-of-pocket costs, including deductibles.

Some Medicare Advantage plans have reduced their dental and vision coverage, for example, and raised co-pays to see specialists. If you signed up for a gym membership through a Medicare Advantage plan, you may be shocked to find out that you don’t qualify for that free Pilates class right now.

“The differences between plan premiums, co-pays, and annual deductibles are unusually large, leading to large differences in out-of-pocket costs between plans,” Philip Moeller, a Medicare and Social Security expert who writes the Aging in America newsletter, told Yahoo Finance.

Insurance providers are eliminating plans, hospital plans, and doctors altogether. There are plenty of options still available, so don’t panic. This year, the average beneficiary can choose from 32 Medicare Advantage plans offered by eight firms, according to KFF, a nonprofit health policy research organization.

The two largest Medicare Advantage insurers, UnitedHealthcare and Humana, will offer plans in about 80% of US states by 2026, down from about 90% this year.

The real concern is that you may not have realized that your plan is closing soon. “Some insurers are pulling out of certain markets,” Moeller said.

One reason for the exit: “The Centers for Medicare & Medicaid Services (CMS) blindsided private Medicare Advantage (MA) plans with plans to approve a small 0.9% increase in premiums through 2027,” Moeller said. “As they came under strong criticism of the plans’ pricing and denial-of-care practices, they pulled out of many parts of the country and reduced plan offerings.”

According to a study by researchers at the Johns Hopkins Bloomberg School of Public Health, one in 10 Medicare Advantage enrollees, or up to 2.9 million seniors, “face forced eviction by 2026.”

Medicare Advantage plans are a separate health insurance plan from traditional Medicare for those 65 and older. They are owned by private insurance companies and are growing in popularity.

Just over 35 million people signed up for Medicare Advantage as of Feb. 1, 2026, which is an increase of 1.1 million people from February 2025. The biggest draw of Medicare Advantage plans is that they include coverage for benefits not included in traditional Medicare, such as drug coverage (Part D), glasses, dental coverage, and fitness. In addition, they often have very low or no costs.

That’s tempting. This year, initial Medicare Part B premiums are $202.90, and the annual Part B deductible, which most people must pay before their Medicare starts, is now $283.

There is a breakdown. Unlike original Medicare, depending on the Advantage plan, you are limited to a specific network of doctors and other health care providers, and those networks are constantly changing.

It is rare to be referred to a specialist who is not part of your Medicare Advantage plan network. In those cases, you need pre-authorization to make an appointment, or you simply have to be prepared to pay the bill out of pocket.

For those considering switching to traditional Medicare, that decision takes homework.

Regular Medicare has no caps on various out-of-pocket costs, so you want to enroll in extra coverage through the private Medicare Supplement program — Medigap for short, Moeller says. “These programs will pay most of the approved claims for care that cannot be fully covered by original Medicare.”

The biggest gap that covers many people is that original Medicare only pays 80% of covered Part B costs, which includes doctors, inpatient costs, and durable medical equipment, he added.

For that, you need Medigap health insurance that is sold by private insurance companies that pay part or all of certain remaining costs. Medigap can cover remaining deductibles, coinsurance, and co-payments, and may cover health care costs that Medicare does not cover at all, such as medical care received outside the US.

The hitch is that in most states, the guaranteed right to buy Medigap is limited to the time you first sign up for Medicare Part B. Medicare doesn’t allow Medigap plans to deny you or charge a higher premium because of a pre-existing condition at that time. In most states, your premium, however, will vary depending on factors such as your age, gender, and where you live.

A Medigap guarantee policy is also good if you joined an Advantage plan in your first year of Medicare but were withdrawn within a year and switched to traditional Medicare. After that, however, Medigap plans in many states may reject you if you have a pre-existing condition, such as diabetes. The exceptions are New York, Connecticut, Maine, and Massachusetts.

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If you need to make a change, you can start by contacting your State Health Insurance Assistance Program (SHIP) network, which offers free one-on-one counseling in every state. You can find your local SHIP here.

The Medicare Rights Center offers a toll-free consumer hotline: 800-333-4114. You can also contact Medicare directly at 800-633-4227.

You can research your options with the Medicare Plan Finder. Enter the drugs you take, and it will show you if they are covered by the Advantage plan. When you look at the various plans available where you live, you will see annual cost estimates for that plan based on the drugs you have entered into the tool.

If you have a limited income, you may be eligible for Medicare Supplemental Assistance, which covers Part D premiums and deductibles and drug cost caps.

If a Medicare Advantage plan doesn’t cover the medications you’re taking, but you’re reluctant to switch to a new one, there may be alternatives, so ask your doctor if there’s a drug covered by your existing plan that will work for you.

Kerry Hannon is a Senior Columnist at Yahoo Finance. He is a career and retirement professional and the author of 14 books, including “The Retirement Itch: Gen X’s Guide to Securing Your Financial Future,“”Managing at 50+: How to Succeed in the New World of Work,” and “You’re Never Too Old To Be Rich.” Follow him on Bluesky again X.

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