Form 8858 is the IRS information return a U.S. person files for each foreign disregarded entity (FDE) they own and each foreign branch (FB) they operate. The classic case is an American who owns a single-member company abroad that's treated as disregarded for U.S. tax. It's attached to your income tax return, it's due when that return is due, and missing it carries a $10,000 penalty per entity, per year.
It's an information return, so it usually doesn't change the tax you owe. What it does is tell the IRS what that foreign business earned, what it owns and what moved between it and you. Everything below comes from the IRS Instructions for Form 8858 (Rev. December 2024), checked in October 2026.
What counts as an FDE or a foreign branch
An FDE is an entity that isn't created or organized in the United States and that's disregarded as separate from its owner for U.S. income tax purposes. Many foreign companies become disregarded because the owner filed Form 8832 to choose that classification.
A foreign branch is a business operation abroad that isn't a separate entity at all. For Form 8858 purposes it also includes a foreign qualified business unit, which in plain terms is a distinct activity abroad that keeps its own books.
Two definitions in the instructions matter more than people expect. The tax owner is the person treated as owning the FDE's assets and liabilities for U.S. tax. The direct owner is the legal owner. They're not always the same person, and the filer category you fall into depends on which one you are.
Who must file: the six categories
| Category | Who it covers | What to complete |
|---|---|---|
| 1 | A U.S. person that's directly the tax owner of an FDE or operates an FB | The whole form plus Schedule M |
| 2 | A U.S. person that's the tax owner or operator through one or more tiers of FDEs | The whole form plus Schedule M |
| 3 | U.S. persons filing Form 5471 for a controlled foreign corporation that owns an FDE or operates an FB | Depends on the Form 5471 category |
| 4 | U.S. persons filing Form 8865 for a controlled foreign partnership that owns an FDE or operates an FB | Depends on the Form 8865 category |
| 5 | A U.S. partner in a partnership that applies section 987 to the FDE or FB in a particular way | Form 8858 and Schedule C-1 |
| 6 | Certain U.S. corporations that are partners in a partnership reporting a dual consolidated loss | Lines 1 to 5 and Schedule G lines 10 to 13 |
A U.S. person here means a U.S. citizen or resident alien, a domestic partnership or corporation, a domestic estate or a domestic trust. If you're a U.S. citizen living abroad who owns a local company that's disregarded for U.S. tax, you're usually a category 1 filer.
One form for each entity
This catches a lot of people. If there are tiers, for example one FDE owns another FDE or a branch, you file a separate Form 8858 for each one. You don't fold the lower entity's numbers into the upper one's form.
The IRS example in the instructions: a domestic corporation, A, runs a branch in country X, owns FDE1 in country Y, and FDE1 runs its own branch in country Z. A files three separate Forms 8858, one for the X branch, one for FDE1 and one for FDE1's branch, and the FDE1 form includes only FDE1's own items.
When and where to file
- Work out your filer category from the table above.
- Gather the FDE's or FB's books for the year, kept in its functional currency.
- Complete the identifying information, including the six-digit principal business activity code on line 1h and a three-letter ISO 4217 currency code wherever the form asks for a functional currency.
- Complete the schedules your category requires, such as the income statement, balance sheet and Schedule M for transactions between the entity and related parties.
- Convert amounts to U.S. dollars using the method the instructions set out. Exchange rates are reported as units of foreign currency per 1 U.S. dollar, rounded to at least four places.
- Attach Form 8858 to your income tax return or information return. It's due when that return is due, including extensions.
If you're not the tax owner and you're filing only because of a controlled foreign corporation or partnership, you attach Form 8858 to the Form 5471 or Form 8865 you file for that foreign owner instead.
The penalties
| Failure | Penalty, as of October 2026 |
|---|---|
| Not furnishing the required information on time | $10,000 for each annual accounting period of each entity |
| Still not filed 90 days after an IRS notice | Another $10,000 for each 30-day period, up to a maximum of $50,000 per failure |
| Not filing or not reporting everything required | A 10% reduction in the foreign taxes available for credit, with an extra 5% for each 3-month period after the 90-day mark |
Criminal penalties can also apply under sections 7203, 7206 and 7207 for failing to file the information section 6038 requires. That's why people who discover a missed Form 8858 usually talk to a tax professional about catching up before the IRS writes first.
How it fits with your other foreign filings
Form 8858 doesn't replace other foreign reporting. If you also hold foreign bank accounts above the reporting threshold, the FBAR is a separate filing with its own rules. And if the foreign company isn't disregarded, because it's taxed as a corporation, the relevant return is usually Form 5471 rather than Form 8858.
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The verdict
If you own a foreign company that's disregarded for U.S. tax, or you run a branch abroad, assume Form 8858 applies to you every year, one form per entity. It rarely changes your tax bill, but skipping it costs a lot: $10,000 per entity per year before the continuation penalties start. If you've never filed one and should have, fix it now rather than waiting for a notice.
Sending assets abroad has its own form, and our guide to moving property to a foreign corporation explains the rules.
Frequently asked questions
What is Form 8858 used for?
It's an information return certain U.S. persons file for each foreign disregarded entity they own and each foreign branch they operate.
When is Form 8858 due?
It's due when your income tax return or information return is due, including extensions, and it's attached to that return.
Do I need a separate Form 8858 for each entity?
Yes. If there are tiers of FDEs or branches, the instructions say to complete a separate Form 8858 for each one.
What is the penalty for not filing Form 8858?
A $10,000 penalty for each annual accounting period, plus $10,000 for each 30-day period the failure continues more than 90 days after an IRS notice, up to $50,000 per failure.
Is a foreign branch the same as a foreign subsidiary?
No. A branch is an operation abroad that isn't a separate entity. A foreign subsidiary taxed as a corporation is usually reported on Form 5471 instead.
Does Form 8858 change how much tax I owe?
Not on its own. It reports the entity's income, balance sheet and transactions, which you'll also reflect on your own return because a disregarded entity's results flow to its owner.
