Do I have to report foreign income if I already paid taxes on it abroad?

Yes. U.S. persons must report all worldwide income regardless of foreign taxes paid. However, the Foreign Tax Credit (Form 1116) can help offset double taxation by providing a credit for foreign taxes already paid.

What is the substantial presence test?

The substantial presence test determines whether a foreign national has spent enough time in the U.S. to be treated as a resident for tax purposes. It considers days present in the current year and the two preceding years using a weighted formula.

Can a non-resident alien opt into U.S. worldwide taxation?

Yes. If married to a U.S. citizen or resident, a non-resident alien can elect to be treated as a U.S. resident and file jointly. This may provide certain tax benefits but subjects all worldwide income to U.S. taxation.

Foreign Income Reporting

Foreign Income Overview: U.S. Tax Rules for International Taxpayers

4:15By ForeignLLCTax

Key Takeaways

U.S. citizens and green card holders must report worldwide income to the IRS
Non-resident aliens generally only pay U.S. tax on U.S.-sourced income
Electing to file jointly with a U.S. spouse subjects all worldwide income to U.S. tax
Multiple reporting forms (FBAR, 8938, 5471, 3520) may apply to foreign financial interests
Penalties for non-filing are severe — $10,000 to $25,000+ per form per year

U.S. Worldwide Taxation: The General Rule

The U.S. tax system operates on a worldwide income basis for U.S. persons. If you hold a U.S. passport or green card, you are subject to U.S. tax on all income earned anywhere in the world. Whether your income comes from Tokyo, Hong Kong, Singapore, or any other country, it all belongs on your U.S. tax return.

This applies regardless of the source — freelance income, investment dividends, real estate proceeds, or side business revenue. The location where you earned the money does not exempt it from U.S. taxation if you are a U.S. person.

Non-Resident Aliens and U.S.-Sourced Income

Non-resident aliens — individuals who are neither U.S. citizens nor full-time residents — face different rules. Generally, they only need to pay U.S. tax on U.S.-sourced income. Income earned in other countries is taxed by those local jurisdictions, not by the IRS.

However, there is a significant exception. If a non-resident alien files jointly with a U.S. spouse, they can elect to be treated as a U.S. resident for tax purposes. While this may unlock certain tax benefits, it also subjects all worldwide income to U.S. taxation. This decision should be made carefully.

Key Foreign Income Reporting Forms

U.S. persons with foreign financial interests face multiple reporting obligations beyond the standard tax return. These include the FBAR (FinCEN Report 114) for foreign bank accounts exceeding $10,000 in aggregate, Form 8938 (FATCA) for foreign financial assets above certain thresholds, Form 5471 for ownership in foreign corporations, and Form 3520 for transactions with foreign trusts or receipt of large foreign gifts.

Each of these forms carries significant penalties for failure to file, ranging from $10,000 to $25,000 or more per violation. Understanding which forms apply to your situation is critical for compliance.

foreign incomeFBARform 8938FATCAforeign reporting