Are you subject to the Net Investment Income Tax?
The NIIT, commonly referred to as the Medicare surtax, went into effect at the start of 2013 and applies to individuals, trusts and estates.
As an individual taxpayer, you will face the 3.8% surtax if you have net investment income (NII) and modified adjusted gross income (MAGI) over the following thresholds, which are never inflation-indexed:
Married filing jointly, qualifying widow(er) $250,000
Married filing separately $125,000
Single, head of household$200,000