How do I claim the foreign tax credit on Form 1116 to avoid double taxation?

The U.S. taxes its citizens and residents on worldwide income, which means the same income can be taxed by both the U.S. and the foreign country where it is earned. The foreign tax credit (FTC) under Section 901 prevents this double taxation by allowing you to credit the foreign taxes you pay against your U.S. tax liability on the same income. Form 1116 ("Foreign Tax Credit") is the form used to compute and claim this credit. For most U.S. expats paying significant foreign taxes, the FTC is the primary mechanism for avoiding double taxation.

You have two options: claim foreign taxes as a credit (Form 1116) or as an itemized deduction (Schedule A). The credit is almost always more beneficial because it reduces your tax liability dollar for dollar, while a deduction only reduces taxable income (providing a benefit equal to the tax rate times the deduction). For example, if you pay $10,000 in foreign taxes and are in the 24% bracket, the credit saves you $10,000 in U.S. tax while the deduction would only save you $2,400. The only scenario where the deduction might be preferable is if your foreign taxes exceed the FTC limitation and you cannot use the excess as a carryover.

The FTC is not a simple dollar-for-dollar credit — it is subject to a limitation calculated separately for different categories ("baskets") of income. The main categories are: general category income (most active business income, wages, self-employment income), passive category income (dividends, interest, rents, royalties), Section 951A category (GILTI income), foreign branch income, and treaty-sourced income (Section 865(h)). You must compute the FTC limitation separately for each category. This means excess credits in one category cannot offset a limitation shortfall in another category.

The FTC limitation for each category is: (Foreign source taxable income in the category / Total worldwide taxable income) x U.S. tax liability. This formula ensures you cannot use foreign tax credits to offset U.S. tax on U.S.-source income. If your foreign tax rate is higher than your effective U.S. rate on the same income, you will have excess credits that cannot be used currently. These excess credits can be carried back 1 year and carried forward 10 years to years where the limitation allows their use.

If you also claim the Foreign Earned Income Exclusion (FEIE) on Form 2555, be aware that the FTC and FEIE interact. You cannot claim the FTC on income that is excluded under the FEIE. The excluded income is removed from both the foreign source income numerator and the worldwide income denominator in the limitation formula, which can reduce or eliminate the FTC for expats who use both provisions. Many expats find that the FTC alone (without the FEIE) produces a better overall result, particularly when living in countries with tax rates equal to or higher than U.S. rates, like the Netherlands.

File a separate Form 1116 for each applicable category of income. Convert foreign taxes to U.S. dollars using the appropriate exchange rate (either the rate on the date paid or an annual average rate — be consistent). Keep detailed records of foreign taxes paid, including tax returns filed in the foreign country and payment receipts. If your total creditable foreign taxes are $300 or less ($600 for married filing jointly) and all taxes are on passive income, you may be eligible to claim the credit directly on Form 1040 without filing Form 1116.