Medicare Advantage — officially called Medicare Part C — has become the dominant way Americans over 65 receive their Medicare benefits. As of 2025, more than 33 million beneficiaries were enrolled in Medicare Advantage plans, representing over 54% of all Medicare-eligible Americans, according to CMS.gov data. That number has grown every single year for more than a decade, and it's not hard to understand why: most Medicare Advantage plans bundle hospital coverage, doctor visits, and prescription drugs into a single plan, often with a $0 monthly premium on top of your Part B premium. But the sheer volume of choices — and the aggressive marketing that surrounds them — makes it genuinely difficult to figure out which plan is actually best for your situation.
The first thing to understand is that there is no single "best" Medicare Advantage plan nationally. The plans available to you depend entirely on where you live. A county in Florida might have 50 or more plan options from a dozen carriers, while a rural county in Wyoming might have three. The major national carriers — UnitedHealthcare, Humana, Aetna, Anthem (operating as Elevance Health), and Blue Cross Blue Shield affiliates — dominate enrollment, but regional plans like Kaiser Permanente, SCAN Health Plan, and Highmark often outperform them on quality metrics in the markets where they operate. The lesson here is that brand recognition is not a substitute for checking what's actually available and rated in your specific zip code.
Star ratings are the most standardized quality tool available to Medicare beneficiaries, and they deserve serious attention. CMS rates every Medicare Advantage plan on a scale of 1 to 5 stars, measuring things like how well plans manage chronic conditions like diabetes and heart disease, how quickly members can get appointments, how often members complain about the plan, and whether the plan helps members stay current on preventive screenings. A 5-star plan is considered excellent; 4 stars is above average; 3 stars is average. Plans rated below 3 stars for three consecutive years can be terminated by CMS. According to CMS.gov data for the 2025 plan year, approximately 31% of Medicare Advantage enrollees were in plans rated 4.5 stars or higher, while roughly 7% remained in plans rated 3 stars or below — a gap that can translate into meaningfully different care experiences.
One of the most important — and most overlooked — numbers in any Medicare Advantage plan is the annual out-of-pocket maximum. In 2026, CMS caps the in-network out-of-pocket maximum at $9,350 for Medicare Advantage plans. Some plans set their limit lower, at $4,000, $5,000, or $6,000, which provides significantly more financial protection if you face a serious illness or hospitalization. A plan with a $0 monthly premium but an $8,500 out-of-pocket maximum could cost you far more in a bad health year than a plan charging $75 per month with a $4,500 cap. When comparing plans, always look at the out-of-pocket maximum alongside the premium — not instead of it. Also check whether the plan has a combined in-network and out-of-network limit or only an in-network limit, because the difference matters enormously if you travel frequently or split time between two states.
Prescription drug coverage — Part D — is bundled into most Medicare Advantage plans, and this is where many beneficiaries get surprised by costs they didn't anticipate. Every plan has a formulary, which is its approved list of covered drugs, organized into tiers. Tier 1 drugs (usually generics) might cost $0 to $5 per fill. Tier 3 or Tier 4 drugs (brand-name or specialty medications) can cost hundreds of dollars per fill even with coverage. Before enrolling in any Medicare Advantage plan, run your specific medications through the plan's formulary tool on Medicare.gov. A plan that doesn't cover your blood thinner, your insulin, or your rheumatoid arthritis medication at a reasonable cost tier is not a good plan for you, regardless of its star rating or premium. The Medicare.gov Plan Finder tool allows you to enter your exact medications and dosages and will calculate your estimated annual drug costs under each plan — use it.
Network type is another structural difference that affects how you use your plan day to day. Health Maintenance Organization (HMO) plans typically require you to use a defined network of doctors and hospitals and require referrals to see specialists. Preferred Provider Organization (PPO) plans allow you to see out-of-network providers, though usually at higher cost-sharing. HMO Point-of-Service (HMO-POS) plans offer a middle ground. If you have established relationships with specific specialists — a cardiologist, an oncologist, a rheumatologist — verify that those providers are in-network before you enroll. Provider networks change every January 1, and a doctor who was in-network last year may not be this year. Call the provider's office directly to confirm network participation; don't rely solely on the plan's online directory, which can lag behind real-world changes.
Extra benefits are heavily marketed by Medicare Advantage plans and worth evaluating carefully — but with realistic expectations. Many plans in 2026 offer dental, vision, hearing, fitness memberships (like SilverSneakers), over-the-counter allowances, and transportation benefits. These can provide genuine value: a plan offering $2,000 in annual dental coverage, $300 in vision benefits, and a $100 quarterly OTC allowance is offering real money. But these benefits are only valuable if you'll actually use them, and the details matter. A dental benefit that covers only preventive cleanings and X-rays but excludes crowns, root canals, and dentures is far less valuable than one that covers comprehensive dental care. Read the Summary of Benefits carefully, not just the marketing materials, and compare the actual coverage limits rather than the headline numbers.
Data Snapshot: According to CMS.gov Medicare Advantage enrollment data, there were approximately 3,959 Medicare Advantage plans available nationwide for the 2025 plan year, down slightly from prior years as some insurers consolidated or exited markets. The average Medicare Part B premium in 2025 was $185.00 per month, which beneficiaries pay regardless of whether they choose Original Medicare or Medicare Advantage. Among Medicare Advantage plans, the average monthly plan premium (on top of Part B) was approximately $17 per month in 2025, though a significant share of plans carried a $0 additional premium. These figures shift annually, and 2026 plan-specific premiums should be verified directly through Medicare.gov's Plan Finder.
The five largest Medicare Advantage carriers by enrollment — UnitedHealthcare, Humana, CVS Health/Aetna, Elevance Health, and Kaiser Permanente — collectively cover the majority of Medicare Advantage enrollees. UnitedHealthcare consistently holds the largest market share, with Humana a strong second particularly in the South and Southeast. However, market share does not equal quality. Kaiser Permanente's Medicare Advantage plans have historically earned some of the highest star ratings in the country, frequently achieving 5 stars in California, Colorado, and the Pacific Northwest. Regional plans like SCAN Health Plan in California and Tufts Health Plan in New England also consistently outperform national carriers on member satisfaction metrics. If a high-quality regional plan operates in your area, it deserves serious consideration alongside the national names you see advertised on television.
Enrollment timing is critical and non-negotiable. The Annual Enrollment Period (AEP) runs October 15 through December 7 each year — this is when you can switch from Original Medicare to Medicare Advantage, switch between Medicare Advantage plans, or drop Medicare Advantage and return to Original Medicare. Changes made during AEP take effect January 1. If you miss AEP, the Medicare Advantage Open Enrollment Period (OEP) runs January 1 through March 31, during which you can switch Medicare Advantage plans or return to Original Medicare once. Outside these windows, you generally need a Special Enrollment Period (SEP) triggered by a qualifying life event — moving to a new service area, losing employer coverage, or qualifying for Extra Help with drug costs, among others. Enrolling in the wrong plan and being stuck with it for a year is a real and common problem; mark these dates on your calendar.
If you're comparing Medicare Advantage to Original Medicare paired with a Medigap supplemental policy, the calculus is genuinely complex and depends on your health status, financial situation, and how much you value provider flexibility. Original Medicare plus a Medigap Plan G policy gives you access to virtually any doctor or hospital in the country that accepts Medicare — roughly 93% of all physicians — with very predictable out-of-pocket costs. The tradeoff is that Medigap premiums can run $150 to $300 or more per month depending on your age, gender, and location, and Medigap policies don't include drug coverage, requiring a separate Part D plan. Medicare Advantage typically costs less upfront but involves networks, referrals, and potentially higher costs if you get seriously ill. Neither approach is universally better — the right answer depends on your specific doctors, medications, and financial priorities.
For beneficiaries who want help navigating these choices without sales pressure, State Health Insurance Assistance Programs (SHIPs) offer free, unbiased counseling in every state. SHIP counselors are trained volunteers and staff who can walk you through plan comparisons, help you understand your Summary of Benefits, and flag potential problems — at no cost and with no obligation to enroll in anything. Find your local SHIP through Medicare.gov or by calling 1-800-MEDICARE. Additionally, Medicare.gov's Plan Finder tool is the most comprehensive and unbiased comparison resource available — it pulls real-time data on premiums, formularies, star ratings, and provider networks for every plan in your zip code. Using it before making any enrollment decision is one of the most valuable 30 minutes you can spend on your healthcare.