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Do I owe the 3.8% net investment income tax abroad?
About you
Sets the threshold: $200,000 single or head of household · $250,000 joint or surviving spouse · $125,000 married filing separately.
Your income, in bands
Bands only. Nothing you choose here leaves your browser unless you ask for the result by email.
Everything — salary, investment income, pensions — with any foreign earned income exclusion added back. The exclusion does not lower this number.
Your investments
Your US filing history
Free · no account · bands only. A first screen on bands.
Before you rely on this result
What would settle it, and what covers it
Documents or facts needed
- • Your filing status and modified adjusted gross income for the year (AGI plus any foreign earned income exclusion added back)
- • Investment income by kind: dividends, interest, gains, rents, fund distributions
- • Foreign income tax paid on that income, and to which country
- • Whether any fund or ETF you hold is domiciled outside the US
Where this leads
Simple · $299 — computes Form 8960 next to Form 1116 on your real figures, keeping the credit on the regular tax and off the NIIT.
Also possible: PFIC Portfolio ($499) · Complex ($799). The cheapest route that covers your facts is the right one; a package never covers more than one tax year.
How to read a status
- Likely:
- The facts entered meet the published test; confirm the inputs before acting.
- Possible:
- Some facts point this way and others are missing; more information decides it.
- Needs review:
- These inputs leave it open; a person should look before filing.
- Not currently indicated:
- Nothing entered triggers it this year; a changed fact can change the answer.
- Outside supported scope:
- This item is routed to a professional for preparation.
Scope. A banded screen: the 3.8% is settled by Form 8960 on exact figures, and the result never nets a foreign tax credit against it because the Code and the Federal Circuit (August 31, 2026) allow none. This is a computation on the answers you gave, not individualized tax advice.
Tool: /tools/niit-exposure-check
What changes the result
This answer changes if…
Whether the exclusion or the credit is the better route
- …your foreign income tax rate is above the U.S. rate on the same income — the foreign tax credit tends to leave no U.S. tax and carries excess credit forward; the exclusion cannot.
- …you were in the United States for more than 35 days in the twelve-month period — the physical-presence test for the exclusion is lost for that period.
- …the income is a pension, a distribution or investment income rather than earned income — the exclusion covers earned income only; the credit covers foreign tax on any category.
- …you claimed the exclusion in a prior year and now revoke it — a revocation locks the exclusion out for five years without IRS consent.
- …you have self-employment income — the exclusion does not reduce U.S. self-employment tax; a totalization certificate does.
Whether the 3.8% net investment income tax applies
- …your modified adjusted gross income is below the threshold for your filing status — the tax applies only to the lesser of net investment income and the excess over the threshold.
- …you claim the foreign earned income exclusion — excluded wages are added back for the threshold test.
- …you rely on a treaty to credit foreign tax against this tax — the credit against the net investment income tax rests on a treaty article and on litigated positions, not on Form 1116.
- …a PFIC is under a QEF election — QEF inclusions enter net investment income only under a separate election (the 'section 1.1411-10(g)' election).
Each line names a fact that moves the result; what it moves to depends on the rest of your facts. Nothing here is a determination.
How Atamatax calculations are produced — the tests applied, statutory sources and review cadence — is documented in the methodology, and how the engine is validated in accuracy & review. Calculation fixes are recorded in the changelog.
Authorities cited
- IRC §1411 — IRC §1411 — Net Investment Income Tax (3.8%)
- IRS Form 8960 — About Form 8960 — Net Investment Income Tax (Individuals, Estates, and Trusts)
- Instructions for Form 8960 — Instructions for Form 8960 (2025) — thresholds by filing status, MAGI, lines 1–17, CFC/PFIC adjustments
- IRC §27 — IRC §27 — Taxes of foreign countries and possessions: credit allowed against the tax imposed by chapter 1 to the extent provided in §901
- IRC §901 — IRC §901 — Taxes of foreign countries and U.S. possessions
- Christensen v. United States (Fed. Cir. 2026) — Christensen v. United States, No. 24-1284 (Fed. Cir. Aug. 31, 2026) (precedential) — the U.S.–France treaty's Article 24(2)(a) and 24(2)(b) credits are subject to the Code's §§27/901(a) limitation and do not offset the §1411 net investment income tax; reversing 168 Fed. Cl. 263 (2023)
- Estate of Bruyea v. United States (Fed. Cir. 2026) — Estate of Paul Bruyea v. United States, No. 25-1563 (Fed. Cir. Aug. 31, 2026) (precedential) — the U.S.–Canada treaty's Article XXIV(1) and XXIV(4)(b) credits are subject to the U.S. Law Limitation; the Code and Convention unambiguously preclude offsetting the NIIT by a foreign tax credit; reversing 174 Fed. Cl. 238 (2024)
Primary sources (Cornell Legal Information Institute for the US Code and CFR; IRS.gov for forms, procedures, and treaty documents). This page is general information, not individualized tax or legal advice.
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