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Net Investment Income Tax Calculator (3.8% NIIT, Form 8960)

What does this come to under the current IRS rules?

The lesser of net investment income or the MAGI excess over the filing status threshold, times 3.8 percent.

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Your figures
Example figuresIllustrative only. Type over them with your own.
Net investment income tax (3.8%)
$2,280
NIIT owed
MAGI over the threshold
$120,000
Amount taxed (lesser of NII and excess)
$60,000
Drawn to one scale
MAGI over the threshold$120,000
Amount taxed (lesser of NII and excess)$60,000
Net investment income tax (3.8%)$2,280
All results
MeasureResult
MAGI over the threshold$120,000
Amount taxed (lesser of NII and excess)$60,000
Net investment income tax (3.8%)$2,280
How this was worked out
Work shownrecomputed as you type
Base = lesser of net investment income and (MAGI - threshold)
Tax = 3.8% x base
Thresholds: $250,000 joint, $125,000 separate, $200,000 other

Illustrative arithmetic on the figures you enter. Check the result against your firm's methodology before relying on it.

The formulas

  • Base = lesser of net investment income and (MAGI - threshold)
  • Tax = 3.8% x base
  • Thresholds: $250,000 joint, $125,000 separate, $200,000 other

How it works

Tax year: 2025 and 2026 (thresholds are fixed by statute and not indexed).

The tax is 3.8 percent of the lesser of net investment income or the amount by which modified AGI exceeds the threshold: $250,000 for married filing jointly and qualifying surviving spouse, $125,000 for married filing separately and $200,000 for single and head of household. Net investment income includes interest, dividends, annuities, royalties, rents, passive business income and net gains from property sales. Wages, active business income and tax-exempt interest are not included.

The tax is computed on Form 8960. Estates and trusts use a different threshold and are not covered.

Illustrative figures only. Check the result against your firm's methodology before relying on it.

Common questions

Is the threshold indexed for inflation?

No. The $200,000, $250,000 and $125,000 amounts are the same each year.

What is MAGI for this tax?

AGI increased by the foreign earned income exclusion, with related adjustments. For most people it equals AGI.

Does gain on a home sale count?

Only the part of the gain that is not excluded as principal residence gain.

Sources

Runs in your browser. The figures you type are not sent to CORAA or stored. Check the result against your firm's methodology before relying on it.

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