Foreign Tax Credit Calculator: Estimate Your FTC Limit

Key Inputs Used by the Foreign Tax Credit Calculator

• Worldwide taxable income – Your total taxable income for the year from all sources, U.S. and foreign, before any foreign tax credit is applied. This total matters because the FTC limit is based on your overall tax picture, not just the foreign slice.
• Foreign-source income – The part of your taxable income that U.S. rules treat as foreign-source, such as wages earned while working abroad or foreign interest and dividends. This amount drives the fraction of your U.S. tax that the calculator treats as tied to foreign income.
• Foreign taxes paid – Qualifying foreign income taxes, or taxes paid in lieu of income tax, that were paid directly by you or withheld on your behalf. The calculator compares this amount with the FTC limit to see how much credit can actually be used.
• U.S. filing status – Your filing status (single, married filing jointly, married filing separately, or head of household), which affects the estimated U.S. tax before credits and therefore affects the size of the limitation.

With those inputs, the tool estimates your U.S. tax before credit and then applies the foreign income share to approximate the FTC ceiling. That gives you a fast way to see whether the credit is constrained by the amount of foreign tax you paid or by the amount of U.S. tax attributable to foreign-source income.

The Foreign Tax Credit Limitation Formula

The FTC limitation keeps the credit from reducing U.S. tax that belongs to domestic income. Even when you paid substantial foreign tax, the credit cannot exceed the part of your U.S. tax that relates to foreign-source income.

Formula: F T C l i m i t = (F o r e i g n s o u r c e i n c o m e) / (W o r l d w i d e i n c o m e) × U. S t a x b e f o r e c r e d i t

Read the formula this way:

• Foreign source income – The portion of your total income that the IRS treats as foreign-source for FTC purposes.
• Worldwide income – Your full taxable income from all sources, used as the denominator in the limitation ratio.
• U.S. tax before credit – Your estimated U.S. income tax liability before the foreign tax credit is applied.

The calculator estimates your U.S. tax before credit based on your filing status and taxable income. It then multiplies that tax by the ratio of foreign-source income to worldwide income to estimate your FTC limit. Your allowable credit is the smaller of the foreign income taxes you paid and the amount produced by the limitation formula.

Interpreting Your Foreign Tax Credit Results

After you enter your foreign income information, the results show whether the FTC is limited by the tax you paid abroad or by the portion of U.S. tax tied to foreign-source income.

• Estimated U.S. tax before foreign tax credit – Based on your worldwide taxable income and filing status.
• Computed FTC limitation – The maximum foreign tax credit the simplified formula allows for the year.
• Allowable foreign tax credit – The smaller of your foreign taxes paid and the FTC limitation.
• Effective remaining U.S. tax – Your estimated U.S. tax after the allowable foreign tax credit is subtracted.

If your foreign taxes paid are:

• Less than or equal to the FTC limit, the calculator will usually show that the foreign taxes can be used in full as a credit.
• Greater than the FTC limit, the credit will be capped, and the tool will show that some foreign taxes are not currently creditable under this simplified model.

On a real U.S. return, the final foreign tax credit is computed on Form 1116 and then carried through Schedule 3 and Form 1040. This calculator is designed to approximate the limitation concept so you can understand the result, not to produce a filing-ready amount.

Worked Example: foreign taxes above the FTC limit

This foreign tax credit example shows what happens when qualifying foreign taxes are higher than the FTC limit.

• Worldwide taxable income: $100,000
• Foreign-source income: $40,000 (for example, wages earned while working abroad)
• Foreign income taxes paid: $12,000

Assume your estimated U.S. tax before credits on $100,000 as a single filer is about $17,000 (the calculator will estimate this for you based on current brackets).

First, compute the ratio of foreign-source income to worldwide income:

• Foreign-source income / Worldwide income = $40,000 / $100,000 = 0.40 (40%).

Next, apply the limitation formula:

• FTC limit = 40% × $17,000 = $6,800.

You paid $12,000 of qualifying foreign income taxes, but the FTC limit is $6,800. Under this simplified model, your allowable foreign tax credit is:

• Allowable FTC = min($12,000, $6,800) = $6,800.

Your remaining U.S. income tax after the credit would be approximately:

• U.S. tax after FTC = $17,000 − $6,800 = $10,200.

In a real Form 1116 computation, any excess foreign taxes above the limitation might be carried back one year or carried forward up to ten years. This calculator does not compute carrybacks or carryforwards.

Foreign Tax Credit vs. Foreign Earned Income Exclusion

When you earn money abroad, the foreign tax credit calculator is only one part of the planning picture, because some taxpayers also compare the foreign tax credit with the foreign earned income exclusion (FEIE). You generally cannot use both benefits on the same income.

This calculator only estimates the foreign tax credit side of that decision. It does not calculate the foreign earned income exclusion or compare the numerical benefit of both approaches.

What Counts as a Qualifying Foreign Tax?

For foreign tax credit purposes, the payment has to be a qualifying foreign income tax, not just any charge from a foreign government. In general, creditable taxes are:

• Imposed by a foreign country or U.S. possession.
• Income taxes or taxes in lieu of an income tax.
• Legally owed by you (or withheld on your behalf) and not a voluntary payment.

Common examples that do not qualify for the credit include:

• Value-added tax (VAT) or goods and services tax (GST).
• Sales taxes, excise taxes, or customs duties.
• Property taxes and estate or inheritance taxes.
• Employee social insurance contributions that are not treated as income taxes under U.S. rules.

If you are unsure whether a foreign tax qualifies, professional advice or detailed IRS guidance may be necessary.

Calculator Assumptions & Limitations

This foreign tax credit calculator makes a few simplifying assumptions so the estimate stays easy to read. Before relying on the output, keep in mind that the calculator:

• Uses a single income basket – It assumes one combined category of foreign income. Actual Form 1116 rules may require separate calculations for passive income, general income, and other categories.
• Does not compute carrybacks or carryforwards – Any excess foreign taxes above the limitation are not tracked across years.
• Applies simplified U.S. tax estimation – U.S. tax before credits is estimated based on basic rates and your filing status, without modeling every possible deduction, credit, or special rule.
• Does not apply treaty-specific rules – The impact of income tax treaties, re-sourced income, or special treaty positions is not reflected.
• Is for general education – It is not a substitute for IRS forms, tax software, or personalized advice from an international tax professional.

Because foreign tax credit rules are complex and fact-specific, consider using this calculator as a starting point for understanding your situation and discussing it with a qualified advisor, especially if you have multiple countries, large amounts of foreign income, or mixed types of income such as wages, interest, and dividends.