NIIT Calculator
Calculate the 3.8% Net Investment Income Tax on high-income investment earnings.
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Applies 3.8% to the lesser of your net investment income or the amount your MAGI exceeds $200,000 (single) / $250,000 (joint) — these thresholds aren't inflation-adjusted.
Worth Knowing
The Net Investment Income Tax is a 3.8% surtax on investment income — interest, dividends, capital gains, rental income — that applies once your modified adjusted gross income crosses $200,000 single or $250,000 joint. It's levied on the smaller of your net investment income or the amount you exceed the threshold by. Introduced to help fund the Affordable Care Act, it effectively raises the top capital-gains rate to 23.8% for high earners.
How to Use
- Enter Filing status into the first field of the NIIT Calculator.
- Fill in the rest: Modified adjusted gross income (MAGI), Net investment income.
- Your result appears instantly as you type — there's no submit button or page reload.
- Applies 3.8% to the lesser of your net investment income or the amount your MAGI exceeds $200,000 (single) / $250,000 (joint) — these thresholds aren't inflation-adjusted.