Google 是個好東西 動動手指就找到答案了

https://www.ssa.gov/benefits/medicare/medicare-premiums.html#:~:text=If%20we%20determine%20you%27re,you%20report%20to%20the%20IRS.

 上麵的 社安局 link 有詳細解釋計萛方式

If you have higher income, you’ll pay an additional premium amount for Medicare Part B and Medicare prescription drug coverage. We call the additional amount the “income-related monthly adjustment amount.” Here’s how it works:

• Part B helps pay for your doctors’ services and outpatient care. It also covers other medical services, such as physical and occupational therapy, and some home health care. For most beneficiaries, the government pays a substantial portion — about 75% — of the Part B premium, and the beneficiary pays the remaining 25%.

  If we determine you’re a higher-income beneficiary, you’ll pay a larger percentage of the total cost of Part B based on the income you normally report to the Internal Revenue Service (IRS). You’ll pay monthly Part B premiums equal to 35%, 50%, 65%, 80%, or 85% of the total cost, depending on what you report to the IRS. 

• How Social Security Determines You Have a Higher Premium