What Is Medicare Part C? Complete Guide to Medicare Advantage Plans

Medicare Part C, also called Medicare Advantage, is the private alternative to Original Medicare approved by the federal government. Instead of getting Parts A and B directly from Medicare, you get coverage through a private insurance company that contracts with CMS. The company manages your benefits in exchange for a fixed monthly payment from Medicare. About 35 million people (51% of eligible Medicare beneficiaries) are now enrolled in Medicare Advantage as of 2026, according to KFF data. The Congressional Budget Office projects this share will reach 64% within ten years. Medicare Advantage plans bundle Part A (hospital), Part B (medical), and usually Part D (prescription drugs) into one plan, often adding dental, vision, and hearing benefits Original Medicare doesn't include.

This guide explains what Medicare Part C is, the four main plan types, costs and coverage in 2026, who benefits from Medicare Advantage, and what changed in 2026 that beneficiaries need to know. Information comes from Medicare.gov, CMS, and KFF.

How Medicare Part C works

Medicare Part C operates through a public-private partnership structure. Here's the basic flow:

Step 1: You enroll in a Medicare Advantage plan offered by a private insurer (Humana, AARP/UnitedHealthcare, Aetna, Anthem, etc.) approved by Medicare for your area.

Step 2: You continue paying the standard Part B premium ($202.90/month in 2026) directly to Medicare. Many MA plans charge no additional premium ("$0 premium plans"). About two-thirds of MA enrollees in 2025 had no extra premium.

Step 3: When you need medical care, you use the plan's network of doctors, hospitals, and pharmacies. You pay copays or coinsurance as defined by your plan.

Step 4: The plan pays the providers and tracks your costs against the annual out-of-pocket maximum.

Step 5: Once you hit the OOP maximum (capped at $8,850 in-network for 2026), the plan covers 100% of covered services for the rest of the year.

The federal government pays the Medicare Advantage insurer a capitated rate per member per month to manage your benefits. The insurer profits by managing care efficiently or providing extra benefits to attract members.

For a deeper comparison with traditional Medicare, see our Medicare vs Medicare Advantage guide.

The 4 main Medicare Part C plan types

Medicare Advantage plans come in several forms, each with different network rules and cost structures:

1. HMO (Health Maintenance Organization). The most common type, accounting for about 57% of non-SNP MA plans. HMOs require you to use in-network providers (except for emergencies and urgent care). You typically need a referral from your primary care physician to see specialists. Lower costs are the main advantage. Reduced flexibility is the trade-off.

2. PPO (Preferred Provider Organization). PPOs allow you to see out-of-network providers, though at higher cost-sharing. No referrals required to see specialists in most cases. PPOs cost more than HMOs but offer more flexibility. The 2026 forced disenrollment data showed PPO enrollees were among the most affected by plan exits.

3. PFFS (Private Fee-for-Service). Less common type that lets you see any Medicare-approved provider willing to accept the plan's payment terms. Available in some rural areas where HMO/PPO networks are limited.

4. SNPs (Special Needs Plans). Designed for specific populations: Chronic Condition SNPs (C-SNPs) for people with specific conditions, Institutional SNPs (I-SNPs) for those in long-term care, and Dual Eligible SNPs (D-SNPs) for people with both Medicare and Medicaid. SNPs grew 12.2% in 2026, the largest segment growth, with C-SNP plans increasing 47% to 549 plans available.

In 2026, 5,578 individual Medicare Advantage plans are available nationally, down 1.3% from 2025. The average beneficiary has 32 plan choices.

What Medicare Part C covers in 2026

Medicare Advantage plans must cover everything Original Medicare covers, plus most plans add extra benefits:

Standard Medicare Part C benefits:

• All Part A services (hospital inpatient, skilled nursing facility, hospice)

• All Part B services (doctor visits, outpatient care, preventive services)

• Usually Part D prescription drug coverage included

• Annual out-of-pocket maximum protection

Extra benefits commonly included:

• Dental services (cleanings, fillings, sometimes dentures and crowns)

• Vision care (annual eye exams, eyewear allowance)

• Hearing aids and exams

• Fitness benefits (SilverSneakers or similar)

• Over-the-counter (OTC) drug allowances

• Meal delivery during recovery

• Transportation to medical appointments

• Personal emergency response systems

2026-specific updates:

• Annual Part D out-of-pocket cap of $2,100 (Inflation Reduction Act)

• $35 monthly insulin cap continues

• All ACIP-recommended adult vaccines $0 under Part D

• Expanded caregiver support services (training, respite care)

• Auto-enrollment in Medicare Prescription Payment Plan if previously enrolled

Specific plan benefits vary significantly. See our AARP Medicare Advantage, Aetna Medicare Advantage, and Humana Medicare Advantage 2026 guides for plan-specific details.

Medicare Part C costs in 2026

Medicare Advantage cost structure differs from Original Medicare:

What you always pay:

• Standard Part B premium of $202.90/month

• Part B late enrollment penalty if applicable

• Any IRMAA surcharges based on income

What your MA plan may add:

• Monthly plan premium (often $0, but can be $50-$200 for premium plans)

• Annual deductible (varies by plan, may be $0 for some services)

• Copays for doctor visits ($20-$50 typical for specialist)

• Coinsurance for procedures

• Cost-sharing for medications under Part D

What you save through the OOP maximum: The 2026 out-of-pocket maximum for in-network services cannot exceed $8,850. Some plans set lower maximums. The OOP maximum is the most important financial protection MA offers compared to Original Medicare without Medigap supplement insurance.

For specific plan costs in your state, see our Medicare Advantage Texas and Medicare Advantage Florida state guides.

Major 2026 changes to Medicare Part C

Several significant developments affected Medicare Advantage in 2026:

1. Forced disenrollments spiked. About 10% of MA enrollees (2.9 million people) had their plans exit their county markets in 2026, forcing them to switch plans, according to a Johns Hopkins study published in JAMA. This was up from 6.9% in 2025 and 1% annually between 2018-2024.

2. Plan availability decreased. Total available plans dropped from 5,652 in 2025 to 5,578 in 2026. Average beneficiary choices fell from 34 to 32 plans.

3. SNP segment grew. Special Needs Plans grew 12.2%, faster than overall MA growth of 3%. SNPs now serve 23% of MA enrollees, up from 21% in 2025.

4. Insurer consolidation. Humana's projected 25% MA membership growth in 2026 could make it the largest MA insurer by year-end, potentially surpassing UnitedHealthcare. For-profit insurers control 71% of the MA market.

5. Supplemental benefits scaled back. The generous dental, vision, hearing, and OTC allowances that made Medicare Advantage attractive have been reduced across many 2026 plans as insurers respond to lower payment increases.

Who should consider Medicare Part C

Medicare Advantage may make sense for:

Healthy beneficiaries. Lower upfront costs work for those who don't use many services Beneficiaries in areas with strong networks. Urban and suburban areas typically have better MA networks Those who want bundled coverage. All-in-one simplicity appeals to many Beneficiaries needing extra benefits. Dental, vision, hearing coverage valuable if used regularly Eligible for SNPs. People with specific chronic conditions, institutional residents, or dual eligible beneficiaries often benefit from SNPs designed for their situation

Medicare Advantage may not work well for:

• People who travel frequently or split time between states

• Those with specialty care needs (rare diseases, complex conditions)

• Beneficiaries wanting any-provider flexibility

• People with significant existing medical conditions who may need Medigap supplement protection

For a detailed cost comparison and decision framework, see our Medicare vs Medicare Advantage guide.