Medicare Advantage Plans Explained: How Part C Really Works

What Is a Medicare Advantage Plan?

Medicare Advantage (Part C) is a Medicare-approved health plan sold by a private insurance company that delivers your Part A and Part B benefits in one bundled package. When you enroll, the plan takes over as the way you receive Medicare-covered care. Instead of Medicare paying doctors and hospitals directly, your private plan handles claims, sets copays, and applies its own rules for referrals or approvals.

You still need to be enrolled in Original Medicare Parts A and B to join, and you continue paying the standard Part B premium of $202.90 per month in 2026, an increase of $17.90 from $185.00 in 2025. On top of that, most Medicare Advantage plans wrap in Part D prescription drug coverage, and 98% or more of individual plans add extras like dental, vision, and hearing at no additional premium.

CMS projects enrollment in MA to be 34 million people in 2026, and about three quarters (75%) of enrollees in individual Medicare Advantage plans with prescription drug coverage pay no premium other than the Medicare Part B premium. For a broader Medicare primer, see our complete beginner's guide that covers all four parts side-by-side.

The Four Main Types of Medicare Advantage Plans

Medicare Advantage plans come in four main flavors, and the network rules make a huge difference in how you actually use your coverage.

HMO (Health Maintenance Organization)

HMOs are the most restrictive and usually the cheapest. You pick a primary care physician (PCP) who coordinates your care, and you generally need a referral to see a specialist. Out-of-network care isn't covered except in emergencies. If you value low costs and don't mind staying inside a network, HMOs are hard to beat.

PPO (Preferred Provider Organization)

PPOs give you more flexibility. You can see specialists without a referral, and you can go out of network, though you'll pay more when you do. PPOs typically have higher premiums than HMOs but offer better provider access.

PFFS (Private Fee-for-Service)

PFFS plans let you see any Medicare-approved provider that agrees to the plan's payment terms. There's no strict network in the HMO or PPO sense, but not every provider will accept a given PFFS plan, so you need to confirm before each visit.

SNP (Special Needs Plan)

SNPs are designed for people with specific circumstances: a chronic condition (C-SNP), dual eligibility for Medicare and Medicaid (D-SNP), or institutional care (I-SNP). Every SNP must include Part D drug coverage and tailors its benefits and network to the population it serves.

What Medicare Advantage Actually Costs in 2026

One of the biggest selling points of Part C is the low sticker price. The average monthly plan premium across all MA plans is estimated by CMS to decrease from $16.40 in 2025 to $14.00 in 2026, and the majority of enrollees pay no plan premium beyond their standard Part B premium.

But "premium" is only one piece of the cost puzzle. Here's what to look at:

Every Medicare Advantage plan is required to set an annual out-of-pocket maximum (MOOP) that caps what you spend on Part A and B services each year. CMS caps the 2026 Medicare Advantage in-network out-of-pocket maximum at $9,250, $100 lower than the 2025 cap of $9,350, the first decrease in years. The averages plans actually set are lower: the average out-of-pocket limit for Medicare Advantage enrollees is $5,421 for in-network services and $9,825 for in-network and out-of-network services combined in 2026, with the in-network average higher for PPOs ($6,592) than HMOs ($4,636). Once you hit the MOOP, the plan covers the rest of your covered Part A and B services for the year. Note that starting in 2026, your prescription drug costs are capped separately at $2,100 under Part D and do not count toward the medical MOOP.

Extra Benefits: What's Bundled In

The extras are a huge part of why people choose Medicare Advantage. In 2026, nearly all individual Medicare Advantage plans (98% or more) are offering vision, dental and hearing benefits, as they have in previous years, while the share offering certain other supplemental benefits has declined, such as an allowance for over-the-counter items (66% in 2026 vs. 73% in 2025). Common bundled perks include:

• Dental: cleanings, X-rays, fillings, and often crowns or dentures up to an annual allowance
• Vision: routine eye exams, frames, and lenses or contacts
• Hearing: exams and an allowance toward hearing aids
• Fitness: SilverSneakers, Renew Active, or a comparable gym benefit
• Over-the-counter (OTC): a quarterly card for items like vitamins, band-aids, and pain relievers (offered by 66% of plans in 2026, down from 73% in 2025)
• Transportation: rides to medical appointments in many plans
• Meals: post-hospital meal delivery for a limited period

None of these are covered by Original Medicare, which is why the bundled value looks attractive on paper. Just remember: allowances are capped, network dentists and audiologists may be limited, and the exact benefit list changes every year. For a deeper dive, read our guide on dental, vision, and hearing coverage.

Prior Authorization, Referrals, and the Fine Print

The rules that make Medicare Advantage feel more like commercial insurance are prior authorization and referral requirements. Nearly all Medicare Advantage enrollees (99%) are in plans that require prior authorization for some services, which is rarely used in traditional Medicare. Prior authorization is most often required for relatively expensive services, such as inpatient hospital stays, skilled nursing, home health, imaging, and certain specialist procedures.

Prior authorization is one of the top consumer complaints, and new public reporting is finally putting numbers on it. A recent KFF analysis found that about 12 percent of standard prior authorization requests were denied in 2025, and about 10 percent of expedited requests were denied for Medicare Advantage plans. Good news for enrollees willing to push back: standard prior authorization requests initially denied by Medicare Advantage insurers had a 67% success rate on appeal.

HMOs also require referrals from your primary care doctor before you can see most specialists. PPOs and PFFS plans typically don't. If you already have a strong relationship with a specialist, confirm before you enroll that they are in-network and that no referral hoop stands between you and your next appointment.

Medicare Advantage vs Original Medicare + Medigap

This is the fundamental choice most people face at age 65. Here's the honest side-by-side comparison.

With Original Medicare, you can see any doctor or hospital in the U.S. that accepts Medicare, and you don't need referrals. Paired with a Medicare Supplement Plan G policy (which averages roughly $166 per month at age 65 in 2026), most cost-sharing is covered, making your annual expenses highly predictable. The trade-off is a higher combined monthly premium (Part B + Medigap + standalone Part D), often $200 to $400 more per month than a $0-premium Advantage plan. Learn more about the gaps a Medigap plan fills before deciding.

Medicare Advantage flips that math. Lower premiums, but you're restricted to the plan's network and service area for non-emergency care, and you can't buy a Medigap policy while enrolled in an MA plan. For frequent travelers or snowbirds, Original Medicare + Medigap is usually the safer bet.

How Medicare Advantage Is Funded and Rated

Medicare Advantage plans are paid by the federal government through capitated payments, meaning CMS pays the insurer a fixed monthly amount per enrollee based on the local benchmark and the member's risk score. Plans that keep costs below the benchmark can offer richer benefits or rebate part of the Part B premium back to members.

CMS also assigns each Medicare Advantage contract a Star Rating from 1 to 5 stars, updated annually and released each fall before Open Enrollment. Ratings are based on roughly 40 measures covering member experience, customer service, preventive care, chronic condition management, complaint rates, and drug safety.

For the 2026 Star Ratings, the release of the 2026 data file showed weighted average stars rose slightly, from 3.96 to 3.98. On the top end, eighteen plans achieved a 5-star status, versus only seven last year, and just over 40% of MA contracts earned at least four stars, the threshold that unlocks quality bonus payments plans typically pass along as extra benefits. When comparing plans, treat a 4-star or 5-star rating as a green flag and anything below 3 stars as a warning sign. Note that CMS also recently reworked how Star Ratings are calculated, so year-over-year comparisons aren't perfectly apples-to-apples.

How to Shop Plans by ZIP Code During AEP

The Annual Enrollment Period runs October 15 through December 7 every year. During AEP you can switch from Original Medicare to Medicare Advantage, switch between MA plans, or drop MA to return to Original Medicare. Coverage starts January 1.

Here's a practical 5-step shopping process:

1. Go to Medicare.gov/plan-compare and enter your ZIP code
2. Add your prescription drugs so estimated drug costs are personalized
3. Add your preferred pharmacies to see accurate copays
4. Filter by star rating (4+ is a good starting point)
5. Check that your doctors and hospitals are in-network by calling the plan or checking its provider directory

Compare at least three plans on total estimated annual cost, not just premium. And if you missed AEP, there's also a Medicare Advantage Open Enrollment Period from January 1 to March 31 when you can make one plan change or drop MA entirely. If you're leaning toward leaving Part C, our guide on how to switch from Medicare Advantage to Medigap walks through the underwriting rules.

Who Medicare Advantage Serves Best

Medicare Advantage tends to be a strong fit for people who:

• Are generally healthy and use routine care
• Want dental, vision, and hearing benefits without buying separate policies
• Live in urban or suburban areas with robust networks
• Are comfortable staying in-network and coordinating care through a primary doctor
• Prefer lower monthly premiums even if it means higher copays when they need care

It tends to be a worse fit for people who travel frequently, split time between states, have complex chronic conditions that require out-of-network specialists, or highly value predictable costs and unrestricted provider choice. If you're helping a parent decide, our caregiver's playbook walks through the decision step-by-step.

Frequently Asked Questions

Can I switch from Medicare Advantage back to Original Medicare?

Yes. You can switch during the Annual Enrollment Period (Oct 15 to Dec 7) or the Medicare Advantage Open Enrollment Period (Jan 1 to Mar 31). Just be aware that if you want to add a Medigap policy after dropping MA, you may face medical underwriting outside your initial guaranteed-issue window, meaning insurers can deny coverage or charge more based on your health.

Do Medicare Advantage plans cover me when I travel?

For emergency and urgent care, yes, anywhere in the U.S. For routine care, most MA plans limit you to the service area or network. PPOs offer more flexibility than HMOs, but if you travel often or spend months in another state, Original Medicare paired with Medigap Plan G or Plan N is usually a better fit because it works nationwide.

Why do so many Medicare Advantage plans have a $0 premium?

Because CMS pays the insurer a monthly capitated amount for each enrollee, plans that keep their costs below the benchmark can offer richer benefits or waive the plan premium. You still pay the standard Part B premium of $202.90 per month in 2026, so $0 refers only to the additional plan premium, not the total cost of coverage.

What happens if I miss my Medicare Advantage enrollment window?

You'll generally have to wait until the next AEP to enroll, unless you qualify for a Special Enrollment Period through a life event like moving, losing employer coverage, or becoming eligible for Medicaid. Missing your Initial Enrollment Period around your 65th birthday can also trigger late enrollment penalties for Parts B and D.

Are Medicare Advantage star ratings reliable?

Star ratings are a useful shortcut but not a complete answer. They measure quality at the contract level, which can mask differences between individual plans under the same contract. CMS also recalculated 2026 ratings after industry legal challenges, and methodology has shifted year over year, so comparisons across years aren't perfectly apples-to-apples. Use ratings as a first filter, then dig into the specific plan's network, formulary, prior auth rules, and total estimated cost for your situation.