Medicare Part B

Part B is the medical insurance half of Original Medicare. It pays for medically necessary care you get outside a hospital bed, plus preventive care meant to catch illness early. Doctor services count wherever you receive them: while you are a hospital inpatient, Part A pays the hospital’s bill and Part B pays the doctors.

Most preventive services cost you nothing when the provider accepts assignment, meaning they take the Medicare-approved amount as full payment. Part B’s drug coverage is narrow. It includes a limited set of outpatient prescription drugs and insulin used in a pump that Part B covers as medical equipment, at no more than $35 for a month’s supply. Prescriptions you fill at a pharmacy, including insulin pens, belong to Medicare Part D.

Part B has three layers of cost. The standard premium is $202.90 a month in 2026, up $17.90 from $185.00, and you owe it every month whether or not you use care. The deductible is $283 for the year. After that you usually pay 20% coinsurance on each covered service, with no annual limit in Original Medicare. Outpatient care in a hospital can add a separate copayment to the hospital.

Who you see changes the bill. A provider who accepts assignment can charge only the deductible and coinsurance. A non-participating provider may charge up to 15% above the Medicare-approved amount, called the limiting charge, and may ask you to pay in full at the visit. Medicare pays nothing to a provider who has opted out, except in emergencies.

Because the 20% has no ceiling, many people pair Part B with a Medigap policy, which can pay the coinsurance and, in some plans, the limiting charge, or get their benefits through Medicare Advantage, which has a yearly out-of-pocket limit. Either way, you keep paying the Part B premium.

About 8% of Part B enrollees pay more than the standard premium because of the income-related monthly adjustment amount, or IRMAA. It is based on modified adjusted gross income, your AGI plus tax-exempt interest, from the tax return two years earlier, so 2026 premiums use 2024 returns.

The surcharge works as a set of cliffs, not a gradual phase-in. A single filer with MAGI of $109,000 pays $202.90 a month, while one at $109,001 pays $284.10 every month of the year. At the top the total reaches $689.90. Married people who file separately and lived with their spouse face a harsher table: anything over $109,000 jumps straight to $649.20.

Because of the two-year look-back, the income that sets your first Medicare premiums is earned around 63, and each later year’s income sets the premium two years ahead. A Roth conversion, home sale or large capital gain can raise Part B and Part D premiums two years after the tax is paid.

You can put off Part B without a penalty only while you or your spouse have group health coverage based on current employment. When that job or the coverage ends, whichever comes first, you get an 8-month Special Enrollment Period to sign up; Medicare enrollment periods covers the timing, including how to avoid a gap.

Missing that window is expensive: a late penalty of 10% of the standard premium for each full 12-month period you could have had Part B but didn’t, generally for as long as you have Part B. These kinds of coverage don’t let you wait: