Medicare covers different percentages depending on which part you have and what service you need

Medicare does not cover everything at the same rate. Part A (hospital insurance) covers inpatient hospital stays, skilled nursing care, and hospice at different percentages than Part B (medical insurance), which covers doctor visits and outpatient services. Part D (prescription drugs) has its own cost structure based on which plan you choose. The percentage you pay depends on what service you receive, which part covers it, and whether you have met your deductible that year.

The percentages also change if you have Original Medicare versus a Medicare Advantage plan. Original Medicare is run by the federal government and has set cost-sharing amounts nationwide. Medicare Advantage plans are run by private insurance companies and can charge different amounts, though they cannot charge more than Original Medicare for the same service.

Key Takeaways

  • Part A covers hospital stays at 100 percent after you pay a deductible, but only for the first 60 days; days 61–90 require a daily copay, and days 91 and beyond cost even more.
  • Part B covers doctor visits and outpatient care at 80 percent after you meet your annual deductible; you pay the remaining 20 percent.
  • Part D prescription drug coverage varies by plan and includes a deductible, a coverage gap where you pay more, and a catastrophic phase where Medicare pays 95 percent.
  • Medicare Advantage plans set their own copays and coinsurance amounts but must cover everything Original Medicare covers and cannot charge more than the standard cost-sharing.
  • Supplemental insurance (Medigap) can cover the percentages Medicare does not, though you pay a monthly premium for this additional coverage.

How Part A hospital coverage breaks down by length of stay

Part A covers inpatient hospital stays, but the percentage you pay changes depending on how many days you stay. For days 1 through 60, you pay a deductible (the amount changes each year) and then Medicare covers 100 percent. If you stay longer than 60 days, you enter what Medicare calls the "coinsurance" phase: you pay a daily amount for days 61 through 90, and a higher daily amount for days 91 through 150 (called "lifetime reserve days"). After 150 days in a single hospital stay, you pay 100 percent of the cost.

Skilled nursing facility care follows a similar pattern. After a may have access to hospital stay of at least three days, Medicare covers 100 percent of the first 20 days. For days 21 through 100, you pay a daily coinsurance amount and Medicare covers the rest. After day 100, you pay all costs.

Home health care and hospice have different rules. Medicare covers 100 percent of approved home health services with no deductible or copay. Hospice care is also covered at 100 percent, though you may pay small copays for drugs and inpatient respite care.

How Part B outpatient coverage works

Part B covers doctor visits, outpatient surgery, diagnostic tests, and other services you receive outside a hospital. After you meet your annual deductible, Medicare pays 80 percent of the approved amount for most services, and you pay the remaining 20 percent. This 20 percent is called coinsurance.

The key word is "approved amount." Medicare sets what it will pay for each service. If your doctor charges more than Medicare's approved amount, you may owe the difference — unless your doctor has agreed to accept Medicare's payment as full payment. This is called being "Medicare-participating." Most doctors are, but it is worth asking before your visit.

Some Part B services have different cost-sharing. Preventive services like annual wellness visits, cancer screenings, and vaccinations are covered at 100 percent with no deductible. Mental health services are covered at 80 percent after the deductible, the same as other Part B services.

Part D prescription drug coverage and the coverage gap

Part D is structured in phases, and your out-of-pocket costs change as you move through them. You first pay a deductible (the amount varies by plan). Then you enter the "initial coverage" phase, where you pay a copay or coinsurance for each prescription until your total drug costs reach a certain amount set by Medicare each year.

Once your total drug costs hit that threshold, you enter the coverage gap (sometimes called the "donut hole"). In this phase, you pay a higher percentage of the cost — currently 25 percent for most drugs, though this percentage is slowly decreasing each year. You stay in the gap until your out-of-pocket spending reaches another threshold, at which point you enter the catastrophic phase.

In the catastrophic phase, Medicare pays 95 percent of the cost and you pay 5 percent. This phase continues for the rest of the calendar year. The exact dollar amounts that trigger each phase change every year, so check your plan's materials or call the plan directly to learn your specific thresholds.

Medicare Advantage plan coverage percentages

If you have a Medicare Advantage plan instead of Original Medicare, the plan sets its own copays and coinsurance amounts. These can be lower or higher than Original Medicare, depending on the plan. For example, one plan might charge a $15 copay for a doctor visit while another charges 20 percent coinsurance.

Medicare Advantage plans must cover everything Original Medicare covers, and they cannot charge more than Original Medicare's cost-sharing for the same service. However, they can structure their costs differently. Some plans charge low copays but higher deductibles. Others charge coinsurance instead of copays. You should compare the actual out-of-pocket costs across plans during open enrollment, not just the premium.

Medicare Advantage plans often include coverage that Original Medicare does not, such as dental, vision, or fitness programs. These additional benefits may have their own copays or may be fully covered depending on the plan.

How Medigap supplemental insurance changes what you pay

Medigap is supplemental insurance sold by private companies that covers some or all of the costs Medicare does not. For example, a Medigap plan might cover your Part B coinsurance (the 20 percent you would normally pay), your Part A deductible, or both. Different Medigap plans cover different amounts, and each has a monthly premium you pay in addition to your Medicare Part B premium.

Medigap plans are standardized by the federal government, which means Plan G from one insurance company covers the same things as Plan G from another company. The only difference is the premium. This makes it easier to compare plans — you can focus on price rather than trying to understand different benefit structures.

Medigap does not cover prescription drugs. If you want drug coverage and have Original Medicare, you must also enroll in a Part D plan. Medigap also does not work with Medicare Advantage plans; if you have Medicare Advantage, you cannot buy Medigap.

What to ask your doctor or Medicare about coverage percentages

Before a major service or procedure, ask your doctor's office whether they accept Medicare and whether they are a Medicare-participating provider. Ask what the service will cost you out of pocket, based on your specific plan. Your doctor's office can often tell you the Medicare-approved amount and calculate your share.

You can also call Medicare directly at 1-800-MEDICARE to ask about coverage for a specific service. Have your Medicare number ready. Medicare can tell you whether a service is covered, what your deductible status is, and what you would owe.

If you have a Medicare Advantage or Part D plan, call your plan directly — not Medicare — because your plan sets the actual copays and coinsurance you will pay. Your plan's customer service number is on your insurance card.

Frequently Asked Questions

Does Medicare cover 100 percent of anything?

Yes. Part A covers 100 percent of inpatient hospital stays for the first 60 days after you pay the deductible. Part A also covers 100 percent of approved home health services and hospice care. Part B preventive services like annual wellness visits and cancer screenings are covered at 100 percent with no deductible.

What happens if I go over my Part B deductible early in the year?

Once you meet your Part B deductible, you pay 20 percent coinsurance for the rest of the calendar year. The deductible resets on January 1 each year. You do not have to pay it again until the next year begins.

Can I use Medigap with Medicare Advantage?

No. Medigap supplemental insurance only works with Original Medicare. If you have a Medicare Advantage plan, you cannot buy Medigap. However, Medicare Advantage plans often include benefits like dental and vision that Original Medicare does not cover.

Who pays if my doctor charges more than Medicare approves?

If your doctor is a Medicare-participating provider, they agree to accept Medicare's approved amount as full payment, so you owe nothing extra. If your doctor is not participating, you may owe the difference between what they charge and what Medicare approves. Ask your doctor's office about their Medicare status before your visit.

Does my Part D plan cover all prescription drugs?

No. Each Part D plan has a formulary — a list of drugs it covers. Your plan may not cover every drug your doctor prescribes. If a drug is not covered or requires a higher copay, ask your doctor if there is an alternative on your plan's formulary, or contact your plan to request an exception.