Medicare covers hospital stays, doctor visits, and some preventive care, but not everything

Medicare is divided into four parts, and each one covers different things. Part A covers inpatient hospital care. Part B covers outpatient doctor visits and some tests. Part D covers prescription drugs. Part C (Medicare Advantage) is an alternative to Parts A and B offered by private insurers. What Medicare pays depends on which parts you have and what service you receive — there is no single answer that applies to all situations.

The amount you pay out of pocket varies widely. For a doctor visit covered by Part B, you typically pay 20 percent of the cost after you meet your annual deductible. For a hospital stay under Part A, you pay a flat amount called a copay for the first few days, then nothing for days 4 through 60, then a daily copay for days 61 through 90. Prescription drug costs under Part D depend on which drugs are on your plan's formulary and what tier they are on. Understanding what your specific plan covers takes looking at your plan documents, not a general rule.

Key Takeaways

  • Part A covers hospital inpatient stays, skilled nursing facility care after hospitalization, and some home health care; Part B covers doctor office visits, outpatient procedures, and diagnostic tests.
  • You pay different amounts depending on the service: a copay for hospital days 1–3, nothing for days 4–60, a daily copay for days 61–90, and 20 percent of approved charges for most Part B services after your deductible.
  • Part D (prescription drug coverage) requires you to choose a plan during your enrollment period, and your out-of-pocket costs depend on which drugs you take and what tier they are on in your chosen plan.
  • Medicare does not cover dental, vision, hearing aids, or long-term custodial care, though some Medicare Advantage plans offer limited dental or vision benefits.
  • Your plan documents and the official Medicare website are the only reliable sources for what your specific coverage is; coverage rules change yearly.

What Part A covers and what you pay

Part A covers inpatient hospital care — meaning you are admitted to the hospital and stay overnight. It also covers up to 100 days in a skilled nursing facility after a hospital stay of at least three days, and some home health services ordered by your doctor after hospitalization. Part A does not cover outpatient care, doctor office visits, or preventive screenings done outside a hospital setting.

Your costs under Part A depend on how long you stay. For days 1 through 3 of a hospital stay, you pay a copay (the amount changes yearly; in 2024 it is $1,556 per benefit period). For days 4 through 60, Medicare pays everything. For days 61 through 90, you pay a daily copay (in 2024, $389 per day). If you stay longer than 90 days, you have 60 additional "lifetime reserve days" you can use, and you pay a higher daily copay for those. After your lifetime reserve days are exhausted, you pay the full cost.

For skilled nursing facility care, you pay nothing for days 1 through 20. For days 21 through 100, you pay a daily copay (in 2024, $194.50 per day). After day 100 in a benefit period, you pay the full cost. Home health care covered by Part A is free if your doctor orders it and you meet the criteria (homebound status, medical necessity, and skilled care needs).

What Part B covers and what you pay

Part B covers doctor office visits, outpatient hospital services, diagnostic tests like X-rays and blood work, physical therapy, mental health services, and some preventive care screenings. It does not cover routine dental care, vision exams for glasses or contacts, hearing aids, or most long-term care.

For most Part B services, you pay a yearly deductible (in 2024, $240) before Medicare starts paying. After you meet the deductible, Medicare pays 80 percent of the approved amount for the service, and you pay 20 percent. This is called coinsurance. If your doctor does not accept Medicare assignment (meaning they do not agree to charge the Medicare-approved amount), you may owe more than 20 percent.

Preventive services covered by Part B — such as annual wellness visits, mammograms, colonoscopies, and certain blood tests — are covered at no cost to you if your doctor accepts assignment and the service is deemed preventive rather than diagnostic. If the same test is done because you have symptoms, it may be classified as diagnostic and subject to your deductible and coinsurance.

What Part D covers and how to choose a plan

Part D covers prescription drugs. It is not automatic — you must choose a Part D plan during your enrollment period, which is typically in October and November each year. If you do not choose a plan when you first become may be able to access, you may pay a penalty if you join later.

Each Part D plan has a formulary, which is a list of drugs the plan covers. Drugs are placed in tiers, usually ranging from tier 1 (generic drugs, lowest cost) to tier 5 (brand-name drugs with no generic, highest cost). Your out-of-pocket cost for a drug depends on which tier it is on and which stage of the benefit year you are in. In the initial coverage stage, you pay a copay or coinsurance for each drug. Once you and your plan have spent a certain amount on drugs (in 2024, $5,850), you enter the coverage gap, where you pay a higher percentage. Once your out-of-pocket spending reaches a limit (in 2024, $7,050), you enter catastrophic coverage and pay a small copay for the rest of the year.

The drugs covered and the costs vary significantly from plan to plan. Two people taking the same medication may pay different amounts depending on which Part D plan they chose. You can compare plans on Medicare.gov using the plan finder tool, which shows you the estimated cost for your specific drugs under each available plan.

What Medicare does not cover

Medicare does not cover dental care (cleanings, fillings, extractions, dentures), vision care (eye exams for glasses or contacts, glasses, contact lenses), or hearing aids. It covers one pair of glasses or contact lenses after cataract surgery, but not routine vision correction. It does not cover routine foot care, cosmetic surgery, or weight loss surgery unless medically necessary.

Medicare does not cover long-term custodial care — meaning help with daily activities like bathing, dressing, and eating when that is the only care needed. It covers skilled nursing care (nursing care, physical therapy, wound care) in a facility, but only for a limited time after hospitalization. Once you no longer need skilled care, Medicare stops paying, even if you remain in the facility.

Some Medicare Advantage plans (Part C) offer supplemental benefits not covered by Original Medicare, such as limited dental, vision, or hearing coverage, or fitness programs. These vary by plan and by region. If these services matter to you, you can compare what each available plan offers.

Medicare Advantage (Part C) and what it covers instead

Medicare Advantage is an alternative to Original Medicare (Parts A and B). Private insurance companies offer these plans, and they must cover everything Original Medicare covers, but they can do it with different costs and different networks. Most Medicare Advantage plans have a network of doctors and hospitals you must use (except in emergencies), whereas Original Medicare lets you see any doctor who accepts Medicare.

Medicare Advantage plans often have lower or no monthly premiums than Original Medicare plus a Medigap plan, but they typically have higher out-of-pocket costs when you use care. Many plans cap your total out-of-pocket spending per year, which Original Medicare does not. Some plans include prescription drug coverage (Part D) built in, so you do not choose a separate Part D plan. Some plans offer supplemental benefits like dental or vision, but these vary widely by plan and location.

If you switch from Original Medicare to Medicare Advantage, you cannot use a Medigap policy (supplemental insurance). If you later switch back to Original Medicare, you may not be able to buy a Medigap policy, or you may pay more for it. This is an important decision to understand before you make it.

How to find out what your specific plan covers

The rules and dollar amounts change every year, and they vary by plan. The only reliable way to know what your plan covers and what you will pay is to look at your plan documents. Your insurance company sends you a Summary of Benefits and Coverage (SBC) each year, usually in September or October. This document lists what is covered, what you pay, and what is not covered.

You can also call your plan's customer service number (on your insurance card) and ask about a specific service or drug. Have your plan name and member ID ready. If you are comparing plans before you choose one, use the plan finder tool on Medicare.gov, which lets you enter your drugs and doctors to see estimated costs under different plans.

If you have questions about what Original Medicare covers, you can call Medicare directly at 1-800-MEDICARE (1-800-633-4227). They can tell you whether a specific service is covered under Part A or Part B, but they cannot tell you what your out-of-pocket cost will be — that depends on your plan.

Frequently Asked Questions

Does Medicare cover my doctor's visit if I have not met my deductible yet?

Under Part B, no — you pay the full approved amount until you meet your yearly deductible. Once you meet it, Medicare pays 80 percent and you pay 20 percent coinsurance. Preventive visits (like an annual wellness visit) are covered at no cost even before you meet your deductible, as long as your doctor accepts assignment.

What happens if I stay in the hospital longer than 90 days?

You have 60 lifetime reserve days you can use. For those days, you pay a higher daily copay than days 61–90. Once your lifetime reserve days are used, you pay the full cost of the hospital stay. Lifetime reserve days do not renew each year — once they are gone, they are gone for life.

Can I use the same prescription drug plan every year, or do I have to choose a new one?

You can keep the same plan, but the drugs covered, the tiers, and the costs change every year. It is worth comparing your current plan to other available plans each October during open enrollment, because a different plan might cover your drugs at a lower cost.

If I have Medicare Advantage, do I still need to choose a Part D plan?

Most Medicare Advantage plans include prescription drug coverage, so no — you do not choose a separate Part D plan. However, some Medicare Advantage plans do not include drug coverage, so check your plan documents. If your plan does not include drug coverage and you do not choose a Part D plan, you may pay a penalty if you join one later.

What should I do if my doctor says a service is not covered by Medicare?

Ask your doctor for the specific service code (CPT code) and call your plan or Medicare to confirm. Sometimes a service is covered under certain conditions but not others — for example, a test might be covered if ordered for a specific reason but not for routine screening. Getting confirmation in writing before you have the service can help you avoid unexpected bills.