Additional Medicare Tax

The Additional Medicare Tax is a tax that was introduced as part of the Affordable Care Act (ACA) and is designed to help fund Medicare. It is a 0.9% tax that applies to wages, salaries, and self-employment income above certain thresholds.
The threshold for the Additional Medicare Tax depends on your filing status. For single filers, the threshold is $200,000, for married filing jointly the threshold is $250,000, and for married filing separately the threshold is $125,000.
If you earn above these thresholds, your employer is required to withhold the Additional Medicare Tax from your wages or salary. If you are self-employed, you will be responsible for paying the tax on your own when you file your tax return.
It is important to note that the Additional Medicare Tax only applies to earned income and not to investment income or other types of unearned income.