You live in Japan. You pay Japanese income tax, resident tax, and maybe more. Then you find out the IRS wants you to file a US return on that same income. Does that mean you’re paying tax twice?
Usually not — thanks to the Foreign Tax Credit (FTC). This is one of the main tools Americans in Japan use to reduce double taxation. If you pay eligible income tax to Japan, you can generally use those payments to offset what you owe to the IRS — up to the limit calculated on Form 1116.
This guide explains how the Foreign Tax Credit works, who qualifies, how to calculate it, and how it compares to the Foreign Earned Income Exclusion.
This article discusses 2025 US returns generally filed in 2026 and notes selected 2026 inflation-adjusted amounts where relevant. It is general information for US taxpayers living in Japan and is not tax, legal, or accounting advice. Consult a qualified tax professional for your situation.
What Is the Foreign Tax Credit?
The Foreign Tax Credit lets US taxpayers reduce their US income tax liability for eligible foreign income taxes paid or accrued, subject to the applicable limitation and other rules. It’s a credit, not a deduction, meaning it reduces your tax bill directly rather than just lowering your taxable income.
For example: if your US tax on foreign-source income is $20,000 and you paid $25,000 in eligible Japanese income taxes allocated to that income, the FTC can reduce your US tax to $0 on that income (you don’t get the $5,000 excess back as a refund, but you may be able to carry it forward or back).
The FTC helps prevent the same foreign-source income from being fully taxed by both the United States and the foreign country.
Source: IRS — Foreign Tax Credit
Which Japanese Taxes Qualify?
Not all Japanese taxes count toward the FTC. The tax must be an income tax (or a tax in lieu of an income tax) imposed by a foreign country, and it must meet the IRS creditability tests. Whether a specific Japanese tax qualifies depends on the US rules and the taxpayer’s facts.
Generally Qualifying
- Shotoku-zei (所得税) — National income tax
- Jumin-zei (住民税) — Resident tax (prefectural and municipal). This is an income-based tax and generally qualifies
- Fukko Tokubetsu Shotoku-zei (復興特別所得税) — Reconstruction surcharge on income tax
Generally NOT Qualifying
- Shohi-zei (消費税) — Consumption tax (it’s a sales tax, not an income tax)
- Koteishisan-zei (固定資産税) — Property tax
- Jidosha-zei (自動車税) — Automobile tax
- Social insurance premiums — Health insurance, pension, etc. (these are not taxes)
Source: IRS — What Are Foreign Taxes That Qualify for the Credit | IRS — Publication 514
FTC vs. Foreign Earned Income Exclusion (FEIE)
Americans in Japan have two main tools to avoid double taxation. Here’s how they compare:
Can You Use Both?
You may use the FEIE and FTC in the same return, but you cannot claim a credit for the portion of Japanese tax allocable to income excluded on Form 2555. If only part of your foreign earned income is excluded, Form 1116 requires an allocation that reduces the foreign taxes available for credit.
Form 2555 also uses a tax-stacking calculation that affects the tax rate applied to your remaining income, so the combined result must be modeled rather than assumed. For some Americans in Japan who are in high Japanese tax brackets, using the FTC alone may produce a better outcome than combining both.
Source: IRS — Form 1116 Instructions | IRS — Publication 514 | IRS — Publication 54 | IRS — 2026 Inflation Adjustments
How to Calculate the Foreign Tax Credit
The FTC is not unlimited — the IRS caps it so you can’t use foreign taxes to offset US tax on US-source income. In simplified form, the limitation for each category is:
FTC Limit = US Tax × (Foreign-Source Taxable Income ÷ Worldwide Taxable Income)
The actual calculation involves detailed Form 1116 rules, including allocation of deductions to foreign-source income, capital-gain adjustments, and category-specific calculations.
In simplified terms, for Americans in Japan whose income is mostly Japan-sourced:
- If creditable Japanese tax ≥ US tax on the same foreign-source income → FTC may eliminate your US income tax on that income
- If creditable Japanese tax < US tax → you may owe the difference to the IRS
Japanese tax may eliminate regular US income tax on the same foreign-source income, but the result depends on the Form 1116 limitation, deductions allocated to foreign income, filing status, and the taxpayer’s full return. Other US taxes — such as self-employment tax or the Net Investment Income Tax (NIIT) — may still apply even when the FTC covers your regular income tax.
Income Categories (Baskets)
The IRS requires you to calculate the FTC separately for different income categories. The two most common for employees and ordinary investors are:
- General category — Wages and most earned income
- Passive category — Dividends, interest, rents, and certain gains (subject to sourcing rules and the high-tax kickout)
Other categories exist, including foreign branch income and section 951A (GILTI). Sole proprietors, owners of foreign entities, and taxpayers with capital gains or high-taxed passive income may need to consider additional categories or sourcing rules.
You cannot use excess credits from one category to offset tax in another. This matters if you have both employment income and investment income.
Source: IRS — How to Figure the Credit | IRS — Form 1116 Instructions
How to Claim the Foreign Tax Credit
Step 1: Determine Your Eligible Japanese Taxes
Gather your Japanese tax records. Keep payment receipts, withholding records, assessment notices, and any refund or amended-assessment records:
- Kakutei Shinkoku (確定申告) — Your Japanese final tax return, showing the tax calculated and reported; retain separate evidence of payment
- Gensen Choshu-hyo (源泉徴収票) — Withholding tax statement from your employer (reports withholding and annual employment information; the final liability may differ after assessment or reconciliation)
- Jumin-zei statements (住民税決定通知書) — Resident tax notices from your municipality
- Payment receipts (納付書の控え) — Proof of actual tax payments made
Step 2: Convert to US Dollars
If you claim foreign taxes when paid (cash basis), generally convert each payment or withholding at the exchange rate in effect on the date the tax was paid or withheld.
If you claim foreign taxes when accrued, the average exchange rate for the tax year may apply when the applicable IRS conditions are met; other accrued taxes may use different rules and elections.
Keep records of the exchange rates used for each conversion.
Source: IRS — Publication 514
Step 3: File Form 1116
Complete a separate Form 1116 for each applicable income category. For many employees and ordinary investors, the relevant categories are general and/or passive. Key information needed:
- Country: Japan
- Foreign-source income attributable to Japan, organized by applicable Form 1116 category
- Taxes paid or accrued to Japan (by category)
- Your worldwide income and US tax liability
Small Amount Exception
A limited election may let you claim the credit without Form 1116 if all of the following apply:
- All your foreign-source gross income is passive-category income
- The income and foreign taxes are reported on qualified payee statements (e.g., Form 1099)
- Total creditable foreign taxes are $300 or less ($600 if married filing jointly)
No foreign-tax carryover is allowed to or from a year for which this election is made. For most Americans in Japan paying income tax and resident tax on wages, this election will not apply — you’ll need Form 1116.
Source: IRS — Topic 856, Foreign Tax Credit
Cash vs. Accrual: When to Claim the Credit
Cash-basis taxpayers generally claim qualified foreign taxes in the US tax year they are paid. A cash-basis taxpayer may instead elect on a timely filed original return to claim foreign taxes when they accrue; once made, that election generally applies to all qualifying foreign taxes in later years — you cannot use the paid method for some qualifying foreign taxes and the accrued method for others.
This matters because of timing differences between US and Japanese tax years:
- For many employees, Japanese national income tax is withheld during the year and reconciled through a year-end adjustment. Taxpayers who file a final return generally calculate and settle any remaining balance in the following year’s filing season
- Japanese resident tax based on 2025 income is generally assessed in 2026, with the payment schedule depending on whether it is collected through payroll or paid directly
Source: Japan National Tax Agency — Final Tax Return
Determining when Japanese income tax or resident tax accrues, and handling later changes to the liability (such as refunds or amended assessments), can be complex. If the amount of accrued tax later changes, you may have a foreign-tax redetermination obligation that requires adjusting your US return.
Source: IRS — Publication 514 | IRS — Form 1116 Instructions
Common Situations for Americans in Japan
Salaried Employee
You work for a Japanese company. Depending on your Japanese taxable income and available deductions, national income tax, resident tax, and the reconstruction special income tax may produce substantial creditable foreign tax. Whether that eliminates your regular US income tax depends on the Form 1116 calculation, your filing status, deductions allocated to foreign income, and other factors.
Freelancer / Sole Proprietor
Similar concept for income tax, but watch out for US self-employment tax. The FTC does not offset SE tax (Social Security + Medicare). The Japan-US Totalization Agreement may affect your SE tax obligations if you are covered by Japanese social insurance, but coverage depends on the agreement’s rules and may require a certificate of coverage. See our article on Japanese Social Insurance and US Self-Employment Tax.
Investor with Japanese Dividends or Capital Gains
Japanese tax on foreign-source dividends, interest, rents, or gains may be reported in the passive category, subject to US sourcing, allocation, high-tax-kickout, and capital-gain adjustment rules. You calculate the FTC limit separately for this income. Capital gains require separate source and rate-differential analysis — a gain taxed by Japan is not automatically foreign-source passive income for US FTC purposes.
High Earner (¥20,000,000+)
At high income levels, Japan’s combined tax burden (income tax + resident tax) can be substantial. The FTC may significantly reduce your regular US income tax, but the result depends on sourcing, category, deductions allocated to foreign income, and other factors. If you also have significant US-source income, the FTC limit may restrict how much you can use. Note that the FTC does not directly offset the separately computed Net Investment Income Tax (NIIT).
Excess Credits: Carryback and Carryforward
For most Form 1116 categories, if your qualified Japanese taxes exceed the FTC limit, the excess isn’t lost:
- Carry back 1 year — Apply excess credits to the prior year’s return
- Carry forward 10 years — Use them in future years when you might need them
No carryback or carryforward is allowed for section 951A category foreign taxes, and other restrictions can apply.
Carryovers may be useful in a later year when you again have foreign-source taxable income in the same income category and sufficient FTC limitation. They generally cannot offset tax on US-source income merely because you have unused credits.
If you use or generate a foreign-tax carryover, you may also need Schedule B (Form 1116) for the applicable category.
Source: IRS — Carrying Forward and Carrying Back Foreign Tax Credits | IRS — Form 1116 Instructions
Common Mistakes to Avoid
- Claiming non-qualifying taxes — Consumption tax, property tax, and social insurance premiums don’t count
- Mixing income baskets — General and passive category credits are calculated separately
- Forgetting resident tax — Japanese resident tax is generally creditable when the applicable US requirements are met and is often a significant amount. Don’t leave it out
- Wrong exchange rate — Cash-basis claims use the rate on the date paid; accrual-basis claims follow different rules. Keep records
- Not filing Form 1116 — You must file the form to claim the credit (the small amount exception has narrow conditions most wage earners won’t meet)
- Using FEIE when FTC alone would be better — For some taxpayers in Japan, FTC-only may produce a better result. Model both scenarios
Frequently Asked Questions
If Japan’s tax rate is higher than the US rate, do I owe nothing to the IRS?
Not necessarily. A higher Japanese headline rate does not by itself determine the FTC result. The calculation depends on source, category, deductions allocated to foreign income, filing status, and other factors. In many cases, the FTC may significantly reduce or eliminate regular US income tax on the same foreign-source income — but other US taxes (SE tax, NIIT) may still apply. The FTC does not remove an otherwise applicable filing obligation. If you are required to file a US return and claim the FTC, you generally file Form 1116 unless you qualify for the limited exception described above.
Does the FTC cover self-employment tax?
No. The FTC only offsets income tax, not US self-employment tax (Social Security and Medicare). The Japan-US Totalization Agreement may affect your SE tax obligations if you are covered by Japanese social insurance, but eligibility depends on the agreement’s rules and may require documentation such as a certificate of coverage.
Can I claim the FTC for Japanese taxes paid on prior-year income?
It depends on whether you use the cash or accrual method. Cash-basis taxpayers claim taxes in the year paid. Accrual-basis taxpayers claim taxes in the year they accrue under the applicable rules. The accrual election must be made on a timely filed original return.
What if I forgot to claim the FTC in past years?
A special 10-year limitations period may apply to refund claims attributable to the FTC, measured from the regular due date without extensions for the affected return. Other amended-return issues can have shorter deadlines. If you haven’t been filing at all, the Streamlined Filing Compliance Procedures may be an option, but eligibility is fact-specific.
Source: IRS — Publication 514
Next Steps
- Foreign Earned Income Exclusion (FEIE) — When excluding income makes more sense
- FBAR Filing — Reporting your Japanese bank accounts
- Japanese Social Insurance and US SE Tax — How the Totalization Agreement affects self-employment tax
- Streamlined Filing — How to catch up if you haven’t been filing
