You incorporated a Delaware C-Corp, set up shop in Riverside, and started building. Somewhere between the seed round and your first hire, a quiet pile of federal and state filing obligations started accruing in the background. Miss the wrong one and the penalty is $25,000 before you have earned a single dollar of revenue.
This is the part of being a foreign founder that nobody warns you about. The U.S. does not care that your startup is pre-revenue. It does not care that you live in London or Bangalore or São Paulo. Once a foreign person owns a piece of a U.S. company, a specific set of filing rules switches on, and several of them carry penalties that are flat dollar amounts, not percentages of tax owed. Here is what actually applies to you, in plain language.
This is not legal or tax advice. Consult a qualified professional for your specific situation.
First, the rule that catches almost everyone: Form 5472
If a foreign person owns 25% or more of your U.S. corporation, you have a reporting obligation most founders have never heard of until it is too late.
Form 5472 is an information return for a 25% foreign-owned U.S. corporation. The IRS uses it to see the transactions between your company and its foreign owners or related foreign parties. The form itself creates no tax liability, but failing to file it or filing an incomplete version carries a $25,000 penalty per form per year.
Read that again. The form does not make you owe tax. The penalty is for not filing the paperwork. You can owe zero dollars in actual tax and still be staring at a $25,000 bill because a form was late or incomplete.
The threshold is low and the test is broader than it looks. A corporation is 25% foreign owned if it has at least one direct or indirect 25% foreign shareholder at any time during the tax year, measured by either voting power or value of the stock. One foreign co-founder with a quarter of the cap table is enough.
What counts as a reportable transaction
This is where founders trip. A "reportable transaction" is not just a big sale. It covers sales of goods and property, rentals, royalties, loans and interest payments, services, and the use of property. If your foreign parent entity loans the U.S. company money, that is reportable. If a foreign founder pays a company expense personally, that can be reportable. The routine money movement most founders never think twice about is exactly what this form is built to capture.
The penalty does not stop at $25,000
If you ignore an IRS notice, it compounds. If the failure continues beyond 90 days after IRS notice, an additional $25,000 applies for each 30-day period, with no maximum continuation penalty. There is also no comfortable statute of limitations to hide behind. Failing to file keeps your entire tax return open indefinitely. The IRS can come back years later.
Do NOT treat this as optional housekeeping. For foreign-founded startups, Form 5472 is the single most common five-figure mistake, and it is entirely avoidable. The full mechanics live alongside your federal income tax obligations for foreign-founded startups, since the form is filed with your corporate return.
You need an EIN before you can do almost anything
Your company cannot function without an Employer Identification Number. It is the tax ID for the entity, and you need it to open a U.S. bank account, file returns, run payroll, and accept payments.
Here is the catch foreign founders hit immediately. The IRS online EIN tool is closed to most of you. The online application requires that the responsible party has a valid SSN, ITIN, or existing EIN. If you are a non-resident founder with none of those, you cannot use the fast online route.
TThe fix is straightforward once you know it. You file Form SS-4 by fax or mail, or, if you are outside the U.S., you can call the IRS's international EIN line and complete the application over the phone, which is usually the fastest option. And there is one line that derails people: the responsible party field. Enter "foreign" or N/A on line 7b if the responsible party doesn't have and is ineligible to obtain an SSN or ITIN. That single word is the difference between an approved application and a rejected one that sends you back to the start of a multi-week queue.
One more myth to kill: you do not need a personal tax number to get the company's EIN. The belief that you must first obtain an ITIN to apply for an EIN is wrong, and the sequence usually runs the other way around.
ITIN: your personal tax number, when you actually need one
An EIN is for your company. An ITIN is for you, the individual, and the two are not interchangeable.
You need an ITIN only when you personally have a U.S. tax filing obligation and are not eligible for a Social Security number. If you are a foreign person with no SSN and no eligibility for one, the ITIN is your only option for a personal taxpayer number. You apply with Form W-7, and you have to show a federal tax purpose for it. The W-7 does not travel alone: you attach proof of identity plus either the tax return that requires the ITIN or documentation of another qualifying federal tax purpose.
For a standard C-Corp founder, the entity pays its own tax and you may not personally owe a U.S. return at all. Whether you need an ITIN depends on your specific structure and whether you are taking money out of the company in a way that creates a personal U.S. filing requirement. Do not apply for one reflexively. Apply when a return requires it.
A practical note that saves founders weeks: a foreign passport is the only document that can stand alone to prove both identity and foreign status. If you submit a certified passport copy from the issuing agency, you are done on documentation. Skip it, and you are assembling two or more documents instead.
The corporate return still has to be filed
A foreign-owned C-Corp files Form 1120, the U.S. corporate income tax return, like any other C-Corp. Form 5472 does not replace it. The 5472 is attached to it. The two go together.
If your company is genuinely dormant in a given year, you may have minimal income to report, but the filing obligation and the attached information return do not vanish because business was slow. Pre-revenue is not the same as no-filing. Build the federal return into your annual calendar from year one so it is never a surprise.
Withholding: the trap when money leaves the U.S.
This is the obligation that turns a founder into an accidental tax collector. When your U.S. company pays certain types of income to a foreign person, the company may have to withhold U.S. tax at the source and send it to the IRS.
Withholding only comes into play when the recipient is a foreign person, a category that sweeps in nonresident individuals as well as foreign corporations, partnerships, trusts, and estates. So if your U.S. entity pays a dividend, certain royalties, or certain other U.S.-source income to a foreign founder or a foreign parent company, withholding rules can apply, and the obligation sits on the company as the withholding agent, not on the recipient.
Tax treaties between the U.S. and your home country can reduce or eliminate that withholding, but you do not get the benefit automatically. The foreign recipient generally has to provide the right documentation, and a TIN must be on a withholding certificate when the beneficial owner is claiming an exemption for effectively connected income or other treaty positions. No paperwork, no treaty rate. This is governed by IRS Publication 515, and it is genuinely one of the easier areas to get wrong when you are moving money across borders.
Now the California layer
Everything above is federal. California stacks its own obligations on top, and the state has a reputation among founders for a reason.
The headline is the franchise tax. California's $800 minimum franchise tax applies to any corporation that has incorporated, registered with the Secretary of State, or is doing business in the state. You pay it whether you are profitable, breaking even, or losing money. The one real break: newly incorporated or qualified corporations are not required to pay the minimum franchise tax in their first year. After that, the $800 floor is annual until you formally dissolve.
If you make actual money in California, the rate matters. Every business entity needs an EIN, and so does a sole proprietor running a U.S. trade or business, while the ITIN exists for individuals who cannot get an SSN.
Foreign founders need to understand one more thing about how California defines its reach. A foreign corporation that does not qualify with the Secretary of State, but does business in California, is still subject to the franchise tax. "Foreign" here can mean a Delaware corporation, not just an overseas one. If your Delaware C-Corp is operating in California, the FTB considers you in scope. Where your income is split between California and elsewhere, the state uses apportionment rules to decide how much is taxable here, and how you handle that, including elections like the California Water's Edge Election, can change the result for companies with international operations.
The short version
If you are a foreign founder of a U.S. company touching California, here is your baseline: get an EIN (Form SS-4, line 7b says "foreign"), file Form 1120 every year, attach Form 5472 if a foreign person owns 25% or more and there are reportable transactions, get an ITIN only if you personally have a filing requirement, watch withholding any time money leaves the country to a foreign recipient, and budget for California's $800 franchise tax from your second year forward.
None of these are hard once you know they exist. The expensive part is not knowing. The founders who get hurt are not the ones who made a complex error; they are the ones who never learned the form existed until the $25,000 notice arrived.
When the cross-border layering gets real, with a foreign parent, treaty positions, and multi-state apportionment all in play at once, this is the point to bring in professionals who do startup tax for a living. The Form 5472 and foreign founder compliance details are worth getting right the first time, because the penalties here are not the kind you negotiate down easily.
This is not legal or tax advice. Consult a qualified professional for your specific situation.
FAQ
Do I have to file Form 5472 if my startup made no money?
Yes, if a foreign person owns 25% or more of your U.S. corporation and you had reportable transactions with a foreign related party. The form reports transactions, not profit. A business that had no taxable income and no tax liability still faces the full $25,000 penalty for a missing Form 5472.
Can I get an EIN without an SSN or ITIN?
Yes. You cannot use the online tool, but you can file Form SS-4 by fax or mail. If the responsible party has no SSN or ITIN and is ineligible for one, you enter "foreign" or N/A on line 7b. A common myth is that you need an ITIN first, which is not true.
What is the difference between an EIN and an ITIN?
An EIN identifies your business; an ITIN identifies you personally. Any person other than an individual, and any individual engaged in a U.S. trade or business as a sole proprietor, must have an EIN, while an individual who is not eligible for an SSN uses an ITIN. A foreign founder with a U.S. company often needs the EIN for the company and may need an ITIN personally only if they have a U.S. filing requirement.
Does my company have to withhold tax when it pays me abroad?
Possibly. Withholding applies when a U.S. payer pays U.S.-source income to a foreign person, including a nonresident alien individual or foreign corporation. Treaty benefits can lower the rate, but only if the recipient provides the correct withholding documentation, including a taxpayer ID where required.
Do I owe California franchise tax even though I incorporated in Delaware?
If your Delaware corporation is doing business in California, yes. A foreign corporation that does business in California is subject to the franchise tax even if it has not formally qualified with the Secretary of State. The $800 minimum applies annually after your first year.
When is the California franchise tax actually due?
The minimum tax is owed for each year your corporation exists or does business in California, with a first-year exemption for newly incorporated corporations. After the first year, the $800 minimum is due by the 15th day of the 4th month of your tax year, which means April 15 for calendar-year corporations, regardless of whether the company is active, inactive, or operating at a loss.
