Medicare Part B costs you a monthly premium, an annual deductible, and coinsurance on most services

Medicare Part B covers doctor visits, outpatient care, and preventive services. You pay for it in three ways: a monthly premium taken from your Social Security check (or paid directly if you don't receive benefits), an annual deductible you must meet before Part B starts paying, and coinsurance — typically 20 percent of the cost — on most services after the deductible is met.

The exact amounts change each year. For 2024, the standard monthly premium is $164.90, the annual deductible is $240, and you pay 20 percent coinsurance on most doctor visits and outpatient services. However, preventive care covered by Part B — like annual wellness visits, cancer screenings, and vaccines — costs you nothing after you meet the deductible.

If your income is higher, you pay a surcharge on top of the standard premium. This surcharge, called Income-Related Monthly Adjustment Amount (IRMAA), can range from about $70 to over $500 per month depending on your tax return from two years prior. The Social Security Administration determines your IRMAA automatically and notifies you of any surcharge.

Key Takeaways

  • You pay a monthly premium (standard $164.90 in 2024), an annual deductible ($240 in 2024), and 20 percent coinsurance on most services after the deductible is met.
  • Preventive services like wellness visits and screenings cost nothing once you meet your deductible, but routine care and specialist visits do not.
  • If your income exceeds certain thresholds, you pay an additional surcharge called IRMAA on top of your standard premium.
  • Part B premiums are deducted automatically from your Social Security payment each month, or you receive a bill if you do not receive Social Security.
  • Amounts change yearly; the Centers for Medicare & Medicaid Services announces new premiums and deductibles in October for the following year.

How the monthly premium works

Your Part B premium is deducted from your Social Security benefit each month. If you do not receive Social Security, Medicare sends you a bill. The standard premium amount applies to most people, but your actual premium depends on when you first enrolled in Part B and your income level.

If you delayed enrolling in Part B past age 65 without other coverage, you may pay a late enrollment penalty — an extra 10 percent added to your premium for each year you were may be able to access but did not sign up. This penalty stays with you for life, so the cost of delaying can add up significantly over time.

Higher-income beneficiaries pay IRMAA surcharges. Medicare uses your Modified Adjusted Gross Income (MAGI) from your tax return from two years before the current year. For 2024, if your MAGI is over $103,000 as a single filer or $206,000 as a married couple filing jointly, you pay more. The surcharge increases in brackets as income rises.

Understanding the annual deductible and coinsurance

Before Medicare Part B pays for most services, you must pay the annual deductible out of your own pocket. Once you meet it, Part B covers 80 percent of the approved amount for most services, and you pay the remaining 20 percent as coinsurance.

The deductible resets on January 1 each year. It applies to doctor visits, tests, and outpatient hospital services — but not to preventive care. If you see a doctor in January and pay $300 toward your deductible, then see another doctor in February and pay $100 more, you have now met your $240 deductible for the year. From that point forward, you pay only coinsurance (20 percent) on covered services for the rest of the calendar year.

Coinsurance is not capped under Part B alone. If you have a costly procedure or many doctor visits, your 20 percent share could be substantial. This is why many people also purchase Medigap (supplemental insurance) or enroll in Medicare Advantage (Part C), which may limit your out-of-pocket costs.

What services are free under Part B

Preventive services covered by Part B cost you nothing — no premium, no deductible, no coinsurance — as long as you see an in-network provider and the service is deemed preventive. These include annual wellness visits, colorectal cancer screening, mammograms, bone density tests, diabetes screening, and most vaccines (flu, pneumonia, shingles).

The catch is that once a preventive visit becomes a problem visit — for example, your wellness exam uncovers high blood pressure and the doctor spends time treating it — that portion of the visit may be billed as a regular office visit subject to your deductible and coinsurance. Ask your doctor before the visit whether the appointment is preventive or diagnostic to understand what you might owe.

Income-Related Monthly Adjustment Amount (IRMAA) explained

IRMAA is an extra charge added to your Part B premium if your income is above a certain level. The thresholds and surcharge amounts change yearly. For 2024, single filers with MAGI over $103,000 and married couples filing jointly with MAGI over $206,000 begin paying surcharges.

Medicare calculates IRMAA using your tax return from two years before the current year. If your income changes significantly — for example, you retire mid-year or have a major life event — you can request a recalculation. You must contact Social Security and provide documentation of the change within 60 days of the event. Without a successful appeal, you are locked into the surcharge for the calendar year.

The surcharge brackets are steep. A single filer with MAGI between $103,000 and $129,000 pays about $70 extra per month in 2024, while someone with MAGI over $499,000 pays over $500 extra per month. Married couples have higher thresholds but face similar percentage increases.

How Part B costs compare to other Medicare options

Original Medicare (Part A and Part B) leaves you responsible for the deductible and 20 percent coinsurance on most services. Many people add Medigap to cover these costs, which means paying both a Part B premium and a Medigap premium. Others choose Medicare Advantage (Part C), which combines Part A, Part B, and usually Part D (prescription drugs) into one plan with a different cost structure — typically a lower or zero premium but a copay system and network restrictions instead of coinsurance.

The choice depends on your health, budget, and preference for flexibility. Original Medicare with Medigap offers the most provider choice but costs more upfront. Medicare Advantage limits out-of-pocket costs but restricts which doctors you can see. Understanding your Part B costs is the first step in deciding which path makes sense for you.

When Part B costs change and how to stay informed

Medicare announces new premiums, deductibles, and IRMAA thresholds in October for the following calendar year. The Centers for Medicare & Medicaid Services (CMS) publishes these amounts on Medicare.gov. Your Social Security statement or Medicare bill will show your specific premium for the coming year, including any IRMAA surcharge.

If you believe your IRMAA surcharge is wrong — for example, because your income dropped significantly — you have the right to appeal. You must request a recalculation within 60 days of receiving your notice. Acceptable reasons include retirement, loss of income, death of a spouse, or divorce. Social Security will review your current-year tax return or other income documentation and may adjust your surcharge retroactively.

Frequently Asked Questions

Do I have to pay Part B if I'm still working?

No. If you are still working and covered by your employer's health plan, you can delay enrolling in Part B without penalty. However, you must enroll within eight months of leaving your job or losing employer coverage, or you will face a late enrollment penalty. Check with your employer's benefits office about your coverage timeline.

What happens if I can't afford my Part B premium?

If your income is very low, you may be able to get help paying your premiums through Medicaid or the Medicare Savings Program (MSP), which is run by your state. Contact your state Medicaid office or call 1-800-MEDICARE to learn whether you may have access to. Some states also offer programs that help with coinsurance and deductibles.

Why is my Part B premium higher than my neighbor's?

Your premium is higher if your income is above the IRMAA threshold. Medicare uses your tax return from two years prior, so even if your income has dropped since then, you may still pay the surcharge until the next year's adjustment. You can request an appeal if you had a major life change like retirement or job loss.

Are there any Part B services I don't have to pay coinsurance for?

Yes. Preventive services — annual wellness visits, cancer screenings, vaccines, and certain tests — cost nothing after you meet your deductible. However, if the visit becomes a treatment visit (the doctor diagnoses and treats a condition), that portion may be billed as a regular office visit subject to coinsurance.

Can I get a refund if I overpay my Part B deductible?

No. The deductible does not roll over or refund. Once you meet it, it resets on January 1. If you reach your deductible in November, you still pay the full amount; you do not get credit toward next year's deductible.