Medicare 2026: The Complete Guide to Parts A, B, C, D and Supplement Plans

Focus Keyword: Medicare
Medicare covers more than 65 million Americans, yet surveys consistently show that most beneficiaries don’t fully understand what they have — and what they don’t. The result is avoidable costs, missed benefits, and coverage gaps that hit hardest when health problems arise.

This guide cuts through the complexity. By the end, you’ll understand Medicare’s four parts, how they work together, and how to make the right coverage choices for 2026 and beyond. If you’re still evaluating private health insurance options alongside Medicare, our health insurance guide covers the full landscape.

Who Qualifies for Medicare?

Medicare is a federal health insurance program primarily for Americans 65 and older. You may also qualify before 65 if you:

• Have received Social Security Disability Insurance (SSDI) for 24 months
• Have End-Stage Renal Disease (ESRD) requiring dialysis or a kidney transplant
• Have been diagnosed with ALS (amyotrophic lateral sclerosis), which qualifies immediately upon disability determination

Automatic enrollment: If you’re already receiving Social Security benefits when you turn 65, you’re automatically enrolled in Medicare Parts A and B. If you’re not receiving Social Security yet, you must actively enroll through Social Security during your Initial Enrollment Period (IEP) — the 7-month window that begins 3 months before the month you turn 65.

Medicare Part A: Hospital Insurance

Part A covers inpatient hospital stays, skilled nursing facility care, hospice care, and some home health services.

What Part A Covers

• Inpatient hospital stays: Semi-private room, meals, nursing care, hospital services and supplies
• Skilled nursing facility (SNF) care: After a qualifying 3-day hospital stay, up to 100 days of SNF care per benefit period
• Hospice care: For terminally ill patients with a life expectancy of 6 months or less
• Home health care: Intermittent skilled nursing care, physical therapy, speech-language pathology services when medically necessary

Part A Costs in 2026

• Premium: Most people pay $0 for Part A if they or their spouse paid Medicare taxes for at least 10 years (40 quarters). If you have fewer than 30 work credits, the premium is $518/month in 2026.
• Deductible: $1,676 per benefit period (not per year — per hospitalization episode)
• Coinsurance:
• Days 1–60: $0 after the deductible
• Days 61–90: $419/day
• Days 91–150 (lifetime reserve days): $838/day
• Beyond 150 days: 100% (not covered)

The benefit period concept is crucial: a new benefit period — and new deductible — begins each time you’re admitted to a hospital or SNF after being out for 60 consecutive days.

Medicare Part B: Medical Insurance

Part B covers outpatient care, preventive services, medical supplies, and some home health services.

What Part B Covers

• Outpatient care: Doctor visits, lab tests, X-rays, outpatient surgery
• Preventive services: Annual wellness visits, cancer screenings, vaccinations, diabetes screenings — most at 100% coverage with no cost-sharing
• Durable medical equipment (DME): Walkers, wheelchairs, CPAP machines when medically necessary
• Mental health: Outpatient mental health services, therapy, partial hospitalization
• Second opinions: Before major surgery

Part B Costs in 2026

• Standard premium: $185.00/month (deducted from Social Security benefit for most beneficiaries)
• Income-Related Monthly Adjustment Amount (IRMAA): Higher earners pay more:

• Deductible: $257/year
• Coinsurance: 20% of Medicare-approved amount after deductible (no out-of-pocket maximum in original Medicare)

Medicare Part D: Prescription Drug Coverage

Part D adds prescription drug coverage and is offered through private insurers approved by Medicare.

Key Part D Concepts

Formulary: Each Part D plan maintains a list of covered drugs organized into tiers. Tier 1 (generics) has the lowest cost-sharing; higher tiers cost more. If your medication isn’t on the formulary, you may pay full price — or file an exception request.

The Coverage Gap (“Donut Hole”): In 2026, the coverage gap has been significantly reformed under the Inflation Reduction Act. After you and your plan spend a combined total of $2,000 on covered drugs, you’ll pay $0 for the rest of the year (catastrophic coverage kicks in automatically).

Low-Income Subsidy (Extra Help): If your income is below 150% of the federal poverty level, you may qualify for the Low-Income Subsidy, which eliminates or reduces Part D premiums, deductibles, and copays.

Choosing a Part D Plan

Compare plans at medicare.gov using the Plan Finder tool. Enter your medications, preferred pharmacies, and dosages to see the actual annual cost for your drug list — not just the premium. The cheapest premium plan is rarely the cheapest overall plan.

Medicare Part C (Medicare Advantage): The Alternative Path

Medicare Advantage (MA) plans are offered by private insurers approved by Medicare and must cover everything Original Medicare covers. Most also include Part D drug coverage and additional benefits like dental, vision, and hearing.

Medicare Advantage Pros

• Often lower (or $0) monthly premiums beyond the Part B premium
• Annual out-of-pocket maximums (Original Medicare has no cap)
• Additional benefits: dental, vision, hearing, fitness programs, transportation
• Care coordination through networks

Medicare Advantage Cons

• Network restrictions: HMO plans require you to use network providers; PPO plans cost more out-of-network
• Prior authorization: Many services require pre-approval
• Coverage gaps during travel: Network-based plans may not cover care outside the service area (except emergencies)
• Plan stability: Benefit packages can change annually

Is Medicare Advantage Right for You?

MA tends to work best for people who:
– Are relatively healthy with manageable drug needs
– Prefer to pay as they go (lower premium, higher per-service costs)
– Have preferred providers in the plan’s network
– Want dental and vision bundled in

Original Medicare plus a Medigap supplement tends to work better for people with complex health needs, frequent specialist care, or who travel frequently.

Medigap (Medicare Supplement): Filling Original Medicare’s Gaps

Medigap policies are sold by private insurers to cover the cost-sharing gaps in Original Medicare — deductibles, coinsurance, and copays.

Standardized Plan Letters

Medigap plans are standardized by federal law. Plan G and Plan N are the most popular in 2026:

Plan G: Covers all out-of-pocket costs except the Part B deductible ($257/year). Once you pay that deductible, your exposure is essentially zero for covered services.

Plan N: Similar to Plan G but requires copays of up to $20 for some office visits and up to $50 for ER visits that don’t result in admission. Lower premium than Plan G.

Plan K / Plan L: High-deductible options with lower premiums and built-in out-of-pocket maximums — suitable for people who want catastrophic protection with manageable costs.

When to Buy Medigap

The best time to buy a Medigap policy is during your Medigap Open Enrollment Period — the 6 months beginning the month you’re 65 and enrolled in Part B. During this window, insurers cannot deny coverage or charge more based on your health status (guaranteed issue rights). After this period ends, you may face medical underwriting in most states.

Late Enrollment Penalties: Don’t Miss These Deadlines

Part B late enrollment penalty: If you delay enrolling in Part B without qualifying coverage (employer coverage from a current employer), you pay a 10% penalty added to your monthly premium for each 12-month period you were eligible but didn’t enroll. This penalty is permanent.

Part D late enrollment penalty: 1% of the national base beneficiary premium for each month without creditable drug coverage. Also permanent.

How to avoid penalties: If you have employer insurance through a current employer (or a spouse’s current employer), you can delay Medicare without penalty. COBRA, retiree insurance, and VA benefits are NOT creditable coverage for the purpose of avoiding the Part D penalty.

Common Medicare Mistakes

Not enrolling on time. The Initial Enrollment Period is unforgiving. Missing it means waiting for the General Enrollment Period (January 1–March 31) with coverage beginning July 1 — and potentially paying late enrollment penalties.

Choosing a plan based on premium alone. Total annual cost — premium plus expected out-of-pocket — is what matters, not the monthly premium.

Not reviewing your plan annually. Medicare plans change benefits, formularies, and networks every year. The Annual Enrollment Period (October 15–December 7) is the opportunity to switch plans — and you should evaluate your options every year.

Assuming Medicare covers everything. Original Medicare does not cover routine dental, vision, hearing, or long-term custodial care. These require separate planning.

Frequently Asked Questions

Can I have both Medicare and employer insurance?
Yes. The coordination of benefits rules determine which pays first. If your employer has 20+ employees, employer insurance is primary and Medicare secondary. If the employer has fewer than 20 employees, Medicare is primary.

Is Medicare free at 65?
Part A is free for most people. Part B has a monthly premium ($185/month standard in 2026). Parts C and D have premiums that vary by plan.

What is Medicare’s coverage for dental care?
Original Medicare generally does not cover routine dental care (cleanings, fillings, extractions). Some Medicare Advantage plans include dental benefits.

The Bottom Line

Medicare is not simple, but understanding its structure — Parts A, B, D, and the Advantage vs. Medigap choice — gives you the foundation to make decisions that protect both your health and your finances.

The most important actions: enroll on time, compare plans annually during open enrollment, and think beyond the monthly premium to your total expected annual cost.
This article is for informational purposes only. Contact Medicare at 1-800-MEDICARE or visit medicare.gov for personalized guidance.