Disadvantages of Medicare Advantage

Medicare Advantage (MA) plans cover everything Original Medicare (Medicare Part A and Part B) does, plus usually prescription drugs and vision, hearing, or dental care—all for a low premium. However, compared to Original Medicare, Medicare Advantage plans do have some downsides. Your choice of providers may be more limited, you’re much more likely to need preapproval for expensive care, and your plan can change unexpectedly.

Key Takeaways

• Medicare Advantage offers extra benefits, but out-of-network care may be limited or costly.
• Other disadvantages include difficulty switching out of the plans later, restrictions on care access, and limitations on extra benefits.
• Geographical restrictions also mean you cannot access care if you travel out of state unless you have an emergency or need dialysis.
• Medicare Advantage plans can change benefits annually or drop providers mid-year.
• However, MA plans could be a fit for people on a tight budget or who would qualify for a special needs plan.

Original Medicare vs. Medicare Advantage

Original Medicare, also known as “traditional Medicare,” comprises two Parts, A and B, and you can add prescription drug coverage, called Part D, at extra cost. Medicare Advantage, or Part C, offers Part A and B coverage and usually some form of prescription drug coverage. 

While the federal government administers Original Medicare, private companies sell Medicare Advantage plans, although these plans have to follow the same federal regulations.

Medicare Advantage enrollment has been growing fast in recent years. In 2024, 54% of Medicare-eligible people were enrolled in Medicare Advantage, up from 39% just five years earlier. “With increasing enrollment, expanded supplemental benefits, and ongoing regulatory changes, it’s crucial for both consumers and agents to stay informed,” said Mikh Yusupov, founder of Affordable Care Agents. 

Comparing Medicare Advantage to Original Medicare can quickly become confusing. In short, Original Medicare with a Medicare Supplement (Medigap) plan offers maximum flexibility and coverage but may cost more each month. Medicare Advantage may cost less monthly and has built-in price breaks on annual costs, but may involve more hassles with preauthorization and provider network requirements. Here’s a quick chart to break down the differences.  

Most Original Medicare beneficiaries also buy a Medigap plan, which helps pay expenses such as Medicare’s 20% coinsurance. It can also help pay for foreign emergency coverage. However, Medigap doesn’t offer dental, vision, and hearing coverage. 

Medicare Supplement Plan G or N can offer good cost coverage for those on Original Medicare.

Medicare Advantage Plans May Require You to Get Prior Authorization

Some services, medical supplies, and prescription drugs are not covered immediately with Medicare Advantage. You may need to get prior authorization from your health insurance company for costlier services, which may include inpatient hospital stays or chemotherapy for cancer treatment. The goal is to manage healthcare costs by preventing unnecessary services, but it can delay getting necessary care or prevent its coverage altogether. 

With Original Medicare, you’ll almost never need to get a prior authorization, but you’re much more likely to with Medicare Advantage. About 50 million prior authorization requests were made to Medicare Advantage plans in 2023, or about two for every person enrolled that year. (In contrast, only one person out of a hundred had to get prior authorization for Medicare.)

Of the 50 million MA prior authorizations requested, 3.2 million resulted in a full or partial denial. Although only 12% of denials were appealed, the vast majority that were appealed were overturned, suggesting they the denial may have been wrong in the first place—and also that that contesting MA denials pays off. But that means you’ll need to be tenacious to get through a system of annoying hoop-jumping.

Note

Original Medicare has few prior authorization requirements, which are mainly limited to mobility devices and surgeries that could be classified as either cosmetic or not medically necessary.

You May Need a Referral to See a Specialist

More than half of Medicare Advantage plans are Health Maintenance Organization (HMO) plans, and if you’re enrolled in an HMO and want to see a specialist provider, you’ll need first to talk to your primary care physician and get a referral from them.

In essence, you’ll have to schedule two appointments, one for the primary care doctor and one for the specialist, causing delays in your treatment.

Under Original Medicare, you usually don’t need a referral to see a specialist, although you will need to ensure that the specialist accepts Medicare.

Medicare Advantage Requires You to Visit a Provider in Your Network

With Medicare, you can see any provider who accepts Medicare assignment. That’s 98% of providers, according to the Centers for Medicare & Medicaid Services (CMS).

In contrast, because insurance companies offer Medicare Advantage plans, each can set its own rules about which providers are in its coverage network. If you receive medical treatment from an out-of-network doctor (or another type of medical professional) or at an out-of-network hospital, you might be responsible for all or part of the cost, depending on the type of Medicare Advantage plan you have.

Important

Medicare requires all Medicare Advantage plans to cover emergency or urgent care even when it’s out-of-network. The same is true of out-of-area dialysis. 

Some of the main types of Medicare Advantage plans and what they cover for out-of-network treatment are as follows:

• HMO plans do not cover out-of-network providers.
• HMO point-of-service (HMOPOS) plans may reimburse costs for care received from out-of-network providers if you agree to a higher copay or coinsurance.
• Preferred provider organization (PPO) plans allow coverage for out-of-network providers as long as the provider accepts Medicare and their services are covered by Part A or B. However, expect to pay more for out-of-network care.
• Medical savings account (MSA) plans cover all care from out-of-network providers who accept Medicare, although coverage is limited to your MSA’s balance.

According to research from KFF, Medicare Advantage networks can vary widely. Some narrower networks cover less than 30% of a county’s physicians. People who live in rural areas may have a harder time finding providers.

While MA plans can’t charge you more than 20% for in-network services, there are no limits on out-of-network cost-sharing. As an example, a KFF study found that over a third of MA plan enrollees with out-of-network coverage are charged between 30% and 100% for Part B medications (such as chemotherapy drugs) if administered by an out-of-network provider.

Extra Benefits May Be Limited

Medicare Advantage benefits can sound appealing on brochures or TV commercials that tout “free dental coverage” or “free vision care.”  But the average vision coverage limit is $160, which is much less than what glasses typically cost.

Most dental plan enrollees face dollar limits on how much care is covered in a year, and most are in plans with a maximum cap of $1,000 or less, KFF noted. Some are even in plans with caps as low as $100 to $500. According to the same report, it’s less common to find a plan that covers root canals or dentures.

Fitness benefits can come with restrictions, too. For example, a fitness chain might only allow Medicare Advantage beneficiaries to to visit during certain hours.

Medicare Advantage Coverage Varies From Plan to Plan—And Can Change Every Year

In 2025, there are 3,719 different Medicare Advantage plans. You can only enroll in the plans sold in your area, but the average beneficiary has access to 42 possible plans. Each of these plans is different. It can be challenging to compare them and determine whether they’re the most cost-effective options for you and your health needs.

You’ll have to decide what’s important to you and what trade-offs you’re willing to make. Medicare Advantage plans have different out-of-pocket costs and may offer different services. For example, most MA plans include a Part D prescription drug plan, but some don’t. Their offerings for dental, vision, and hearing services also may vary a lot, and some don’t offer those benefits at all—which are meant to make Medicare Advantage more favorable than Original Medicare.

These options may seem overwhelming if you’re just trying to enjoy your retirement. Original Medicare, by contrast, is just one plan: Everyone receives the same coverage from Part A and Part B.

In addition, every year, Medicare Advantage plans may change. In many cases, this can be good for enrollees. “For those on Medicare Advantage, there may be expanded benefits and incentives, but plan adjustments could vary by provider,” said Innocent Clement, founder and CEO of Ciba Health.

But you should make sure you understand any changes or benefit reductions for a plan you’re enrolled in. For example, according to the KFF, only 65% of Medicare Advantage plans offer meal benefits in 2025, down from 72% in 2024. Your insurer could also decide to eliminate your current plan altogether the following year.

Important

Plans can add or remove providers from their networks at any time of the year. But be aware that the plan is required to make sure your medical care is not interrupted and you have access to benefits deemed medically necessary.

Medicare Advantage Might Not Cover You If You Travel Out of Your State

Your Medicare Advantage plan may be limited to a specific geographic location, called a service area. Service areas can vary by both state and county. Only Original Medicare provides coverage anywhere in the country.

The exception to the MA service area limitation is for coverage of emergency medical treatment or dialysis.

But if you move out of your plan’s service area, you may be disenrolled from your MA plan. At this point, you would be able to sign up for another MA plan in your new service area through a special enrollment period.

In addition, neither Medical Advantage nor Original Medicare cover you while you’re traveling abroad. If you have Original Medicare, you can purchase a Medicare supplement (Medigap) plan to extend your coverage to foreign travel, but Medigap isn’t available for Medicare Advantage beneficiaries. This leads us to the final disadvantage of Medicare Advantage.

You Can’t Purchase Medigap for a Medicare Advantage Plan

Medigap is a supplemental policy for Original Medicare. While you’ll pay an extra premium for it, it will help you pay for out-of-pocket costs, such as your Part A and Part B copays, coinsurance, and deductibles. 

Medigap is not available for Medicare Advantage, so you’ll be responsible for those out-of-pocket costs until you reach your out-of-pocket limit.

Medigap plans give you access to the more flexible coverage from Original Medicare while helping cover the out-of-pocket costs. Medigap plan benefits also do not change every year. However, Medigap plans charge higher premiums than MA plans.

It Can Be Hard to Switch Later If You Want Out of Medicare Advantage

If you try to switch from Medicare Advantage to Original Medicare with Medigap during Medicare open enrollment, you may find an unpleasant surprise. Because your guaranteed issue period has passed, you’ll have to undergo medical underwriting to get a Medigap plan to help cover extra expenses. That means you can be denied coverage or have to pay a lot more.

If you sign up for Medigap when you’re first eligible (within the first six months of your Part B effective date), you won’t have to answer questions about your health and preexisting conditions. This period is known as Medigap open enrollment.

Four states—Connecticut, Maine, Massachusetts, and New York—offer underwriting-free Medigap enrollment outside the initial enrollment period.

The Bottom Line

Medicare Advantage’s supplemental benefits and low premiums make it an attractive alternative to Original Medicare. It’s best for people who can’t afford or get Medigap. Medicare Advantage may also be a good fit for you if your preferred doctor, pharmacy, and hospital is within an existing Medicare Advantage network and you don’t plan to travel much within the U.S. during retirement. 

Just understand that there are trade-offs that could reduce your access to the care you need while potentially leaving you with higher out-of-pocket costs. Ensure you understand the drawbacks before enrolling.