6 Mistakes to Avoid When Selecting Medicare Advantage

There are compelling reasons to consider a Medicare Advantage plan — from bundled prescription drug coverage to extra benefits that Original Medicare simply doesn't include. But before you enroll or switch plans, it's worth knowing the pitfalls that trip up so many beneficiaries. Here are six of the most common mistakes people make, and how to avoid them.

Why should I consider a Medicare Advantage plan?

Before diving into what can go wrong, here's a quick reminder of why Medicare Advantage is worth your attention:

• Medicare Advantage plans improve every year. Insurance providers compete aggressively for enrollees, which means new and better benefits appear regularly. A coverage option that didn't exist last year — or wasn't available in your area — might be available now.
• Prescription drug coverage can shift year-to-year, making regular comparison valuable. If your health has changed and you've added new medications, your current plan may no longer offer the best drug coverage available. Because the majority of Medicare Advantage plans bundle in Part D prescription drug coverage, this is worth evaluating annually.
• Doctor networks are not static. If you're already enrolled in a Medicare Advantage plan, your primary care doctor or a specialist you rely on may have left the network since you enrolled. Checking annually ensures you won't be caught off-guard when you actually need care.
• Better-rated plans continue to expand. Each year, CMS uses a five-star quality rating system to evaluate Medicare Advantage plans. As plans expand into new service areas, you may find a plan with higher star ratings newly available near you — one that could deliver a meaningfully better experience.

When can you enroll or switch Medicare Advantage plans?

• Annual Open Enrollment Period: October 15 – December 7 every year. During this window, you can freely enroll in, disenroll from, or switch between Medicare Advantage plans — including returning to Original Medicare if that's what you prefer.
• Medicare Advantage Open Enrollment Period: January 1 – March 31 each year. Only individuals already enrolled in a Medicare Advantage plan on January 1 can use this period to switch plans or return to Original Medicare.
• Initial Enrollment Period: If you're turning 65, you have a 7-month window — beginning 3 months before your birthday month — to enroll in a Medicare Advantage plan for the first time.
• Special Enrollment Period: Certain qualifying events — such as retiring after 65, moving to a new area, receiving Medicaid or Low Income Subsidy support, or gaining or losing Medicaid eligibility — can trigger a Special Enrollment Period outside the standard windows.

6 Common mistakes to avoid when choosing Medicare Advantage plans

Here are the six most common mistakes we see beneficiaries make when enrolling in or switching Medicare Advantage plans — and what to do instead.

Mistake #1:  Picking the plan your friends recommend

Your friends may rave about their current Medicare Advantage plan — and their enthusiasm is genuine. But their plan was chosen for their doctors, their medications, and their health needs. Yours are different. The plan that works beautifully for a neighbor with a handful of generic prescriptions and a single primary care visit per year may be a poor fit for someone managing multiple chronic conditions or seeing several specialists regularly.

Picking the wrong plan can cost you thousands of dollars annually. Take the time to do your own research — confirming your doctors and drugs are covered, and optimizing around the services you actually use.

Mistake #2:  Misunderstanding differences in provider networks (HMO vs PPO)

HMOs and PPOs are the two most common Medicare Advantage plan structures — and confusing one for the other can lead to serious surprises when you try to access care.

HMO (Health Maintenance Organization) plans typically have lower premiums, but they require you to use in-network providers. You'll need to designate a primary care doctor and usually get a referral before seeing a specialist. Going out of network is generally not covered at all, except in emergencies.

PPO (Preferred Provider Organization) plans cost more but give you the flexibility to see both in-network and out-of-network providers. You don't need a primary care doctor or referrals to see specialists — which matters significantly if you travel frequently, live part of the year in another state, or rely on multiple specialists for ongoing care.

If flexibility in your provider choice is a priority, make sure you fully understand what an HMO's network restrictions would mean for you before signing up.

Mistake #3: Not appropriately checking your drug coverage

In 2026, 89% of Medicare Advantage plans include Part D prescription drug coverage. But not all Part D coverage is equal — and the differences can be financially significant. Drug costs are often the largest day-to-day variable between plans, and a single medication can be in a completely different cost tier depending on which plan you choose.

Each Medicare Advantage plan maintains its own formulary — a list of covered drugs organized into pricing tiers. Formularies can change from year to year, and a drug covered at a low copay this year may be moved to a higher tier next year. Skipping this check can easily cost you hundreds or even thousands of dollars annually.

Mistake #4: Thinking you can buy a separate Part D plan (Prescription Drug Plan)

If your Medicare Advantage plan already includes prescription drug coverage, you cannot also purchase a standalone Part D plan. The two are mutually exclusive. If you attempt to enroll in a standalone Prescription Drug Plan (PDP) while on a drug-inclusive Medicare Advantage plan, you'll be automatically disenrolled from your Medicare Advantage plan — losing all the benefits that came with it.

This is a surprisingly common mistake. Unless you're deliberately choosing to leave Medicare Advantage and return to Original Medicare, don't enroll in a standalone PDP while you're still on a Medicare Advantage plan with drug coverage.

Mistake #5: Fear that your condition will impact your eligibility to switch

Many seniors hesitate to shop for a better Medicare Advantage plan because they worry that their health conditions will disqualify them. This fear is understandable — but it doesn't apply to Medicare Advantage. These plans are prohibited from denying coverage based on health status. As long as you're eligible for Original Medicare, enrolled in Parts A and B, and within an enrollment window, you can join any Medicare Advantage plan available in your area.

It's worth noting that this protection does NOT apply to Medigap (Medicare Supplement) plans. Medigap plans can decline coverage or charge higher premiums based on your health history if you're switching plans outside of a guaranteed issue period. Medigap plans are also only available to beneficiaries on Original Medicare, not Medicare Advantage.

Mistake #6: Fear that your premiums increase from using health care services

Some Medicare Advantage beneficiaries worry that using more healthcare services — seeing doctors frequently, being hospitalized — will cause their premiums to rise the following year. This is not how Medicare Advantage works.

Medicare Advantage plan providers receive a fixed monthly payment from the federal government to cover each enrolled member's health needs. By accepting that payment, they agree to cover your care up to a capped out-of-pocket maximum each year. While you may pay a monthly premium that exceeds the standard Part B premium, that premium is set based on the plan's pricing structure — not your personal health usage.

Final Words

Medicare Advantage plans continue to grow in popularity — and each year, carriers expand their benefits and geographic reach to serve more beneficiaries. The extra coverage these plans offer, from prescription drugs to vision, dental, and hearing care, makes them a genuinely strong option for many people. But the decision to enroll — or to switch — deserves careful attention. Knowing which mistakes to avoid puts you in a far better position to choose a plan that actually works for your life.