Do you actually need an ITIN for your US company?

Short answer: probably not as urgently as you've been told, and possibly not at all.

We sell ITIN services. We'd rather tell you the truth about when you need one, because the number of people who pay for an ITIN they didn't need — or who delay their whole company because they think they need one first — is genuinely depressing.

Here's the complete picture.

What an ITIN actually is

An Individual Taxpayer Identification Number is a nine-digit number the IRS issues to people who have a US tax filing or reporting obligation but aren't eligible for a Social Security Number. It always begins with a 9. It exists for one purpose: so the IRS can identify you on a tax document.

That's the whole thing. It is a tax processing number.

What an ITIN is not:

• It is not work authorization.
• It is not immigration status, and applying for one does not affect any visa application.
• It is not a Social Security Number substitute for anything other than tax filing.
• It is not, by itself, a credit-building instrument. (More on this below, because it's the most expensive misunderstanding in this niche.)
• It is not required to form a US company.
• It is not required to get an EIN.

Those last two are worth repeating, because a large amount of internet advice gets them backwards.

Who genuinely needs an ITIN

You need one if you have a US tax filing or reporting obligation and can't get an SSN. In practice, for the founders we work with, that comes down to a handful of situations:

You have US-source income requiring a return. If your business generates income that's effectively connected with a US trade or business, or you have US-source income subject to reporting, you'll be filing a US return — and you need a taxpayer number to file it.

You're claiming a tax treaty benefit. If your country has a treaty with the US and you want reduced withholding on certain income, you generally need an ITIN to claim it properly.

You're a partner in a US partnership, or a member of a multi-member LLC treated as a partnership. The partnership issues you a Schedule K-1, and that requires a taxpayer number.

You're receiving income where the payer must report and withhold — certain royalties, certain distributions, rental income from US property.

You're selling US real property. FIRPTA withholding requires taxpayer identification.

A dependent or spouse needs one for a return you're filing.

You're opening certain financial accounts where the institution requires a US taxpayer number for its own reporting. This is a real one, though it varies enormously by institution — see the banking section.

Who does not need one (this is most people reading this)

If you are a non-resident who owns a single-member US LLC that is treated as a disregarded entity, has no US employees, no US office, no dependent agents in the US, and no income effectively connected to a US trade or business — you very likely do not need an ITIN at all.

You still have a filing obligation. It's just not one that requires an ITIN.

Here's the mechanism, because this is where people get lost. A foreign-owned single-member LLC is treated as a disregarded entity for income tax purposes, but it is treated as a corporation for reporting purposes under the Section 6038Ai rules. That means it must file Form 5472 along with a pro-forma Form 1120 every year, reporting transactions between the LLC and its foreign owner.

Form 5472 asks for the foreign owner's US taxpayer number if one has been issued. If you don't have one and aren't otherwise required to have one, that field can be handled without you rushing out to obtain an ITIN. What you cannot do is skip the filing — the penalty for failing to file Form 5472 is substantial (commonly cited at $25,000 per form per year — confirm the current figure before relying on it — penalties change).

So the honest hierarchy is:

1. Everyone with a foreign-owned US LLC has a filing obligation (5472 + pro-forma 1120).
2. Only some people have an ITIN obligation.
3. Those are different questions, and conflating them costs people months.

If you're not sure which bucket you're in, that's a question for a US tax professional who works with non-residents — a fifteen-minute consultation, not a service purchase. We'd rather you spend $150 confirming you don't need something than $1,200 buying it.

ITIN vs EIN vs SSN — the three-number confusion

This trips up almost everyone, so here it is plainly:

	What it identifies	Who gets it	Needed to form a company?
SSN	A person authorized to work in the US	US citizens, permanent residents, certain visa holders	No
ITIN	A person with a US tax obligation, ineligible for an SSN	Non-residents and others with filing needs	No
EIN	A business entity	Any business, including foreign-owned	Not to form — but yes, in practice, to operate

You do not need an ITIN to get an EIN. This is the single most common piece of bad advice in the non-resident founder space.

The confusion comes from a real detail: the IRS online EIN application requires the responsible party to have an SSN or ITIN. If you don't have one, the online route is closed to you. But the online route is not the only route. A foreign responsible party without an SSN or ITIN applies using Form SS-4 submitted by fax or by phone to the IRS international line, entering "Foreign" in the responsible party's taxpayer ID field.

That's it. That's the whole workaround, and it's not a workaround — it's the documented process.

Check before you rely on this: IRS international fax and phone processing times fluctuate significantly. Check the current IRS guidance rather than trusting any timeline you read in a blog post, including this one.

How to actually get an ITIN

If you've established that you do need one, here's the real process.

The form

Form W-7, Application for IRS Individual Taxpayer Identification Number. It asks for your identifying information and — critically — a reason code explaining why you need the number.

The reason codes matter more than anything else on the form. The most common rejection cause is a mismatch between the reason you selected and the documentation you supplied.

Common reason categories include: non-resident required to file a US return; US resident filing a return; dependent or spouse of a US citizen/resident; non-resident claiming treaty benefits; non-resident with reportable income requiring an ITIN. Read the current W-7 instructions and select honestly — do not let anyone advise you to select a code that doesn't describe your situation.

The attachment problem

The default rule is that Form W-7 must be attached to a completed US tax return. This surprises people: you generally can't just apply for an ITIN in the abstract.

There are exceptions — documented categories where you can apply without attaching a return, typically involving third-party withholding, treaty claims, or certain financial-account and mortgage situations. Each exception has its own required supporting documentation, usually a letter or statement from the withholding agent or financial institution.

If someone tells you they can get you an ITIN with no return and no exception documentation, they are either cutting a corner or misunderstanding the process. Both end the same way.

The passport problem, and CAAs

Your identity must be proven. A valid passport is the single document that can stand alone; otherwise you're combining two or more documents from the IRS's accepted list.

You have three ways to prove it:

1. Mail your original passport to the IRS. This works. It also means being without your passport for a period that can stretch to months. For most founders this is a non-starter.
2. Get certified copies from the issuing agency — meaning the passport authority in your country, not a notary. Whether this is practical depends entirely on your country's passport office.
3. Use a Certifying Acceptance Agent (CAA). A CAA is authorized by the IRS to verify your original documents and certify them, so your passport never leaves your hands. They submit the W-7 with a Certificate of Accuracy.

Option 3 is why CAA services exist and what most non-residents should use. It's also what we provide — so read the next paragraph with appropriate skepticism and then verify it yourself.

The honest tradeoff: a CAA costs money that mailing your passport doesn't. If you have a spare passport, no travel plans, and patience, mailing is genuinely a valid choice and we'll tell you so. If you have one passport and a life, the CAA fee is buying certainty and your document back. That's the entire value proposition and we're not going to dress it up further.

Timelines

Treat every published timeline as an estimate — and be sceptical of anyone quoting a firm number. IRS ITIN processing times vary by season (there's a heavy backlog around filing deadlines), by whether documentation is complete, and by whether you've applied through a CAA. Any provider who guarantees a specific date is guaranteeing something they don't control.

What you can control: complete documentation, the right reason code, and consistent name spelling across every document. Those three things prevent most rejections.

Renewals and expiry

ITINs expire. An ITIN that has not been used on a federal tax return for a set period will lapse, and certain older ITINs have been subject to scheduled expiry based on their middle digits.

If you're filing with an expired ITIN, the return gets processed but credits and exemptions can be disallowed until you renew, which creates a mess that takes longer to unwind than the renewal would have taken.

Renewal uses the same Form W-7, marked as a renewal. Check the current IRS guidance for the specific expiry rules in effect — this area has changed more than once.

ITINs and credit: read this part carefully

This is where the most money gets wasted in our industry, so let's be precise.

An ITIN does not create a credit file. It is not a credit identity. Obtaining one does not give you a US credit score, and there is no mechanism by which an ITIN by itself generates credit history.

What actually happens is subtler. Some lenders and card issuers accept an ITIN in place of an SSN on an application. If you're approved and the account reports to the bureaus, that account builds history — and the ITIN is the identifier tying it to you. The ITIN is the key, not the engine. The engine is a reporting account with on-time payments over time.

Two further complications that most content ignores:

First, ITIN-associated accounts don't always link cleanly to a credit file. There have been material changes in how ITINs connect to credit records, and accounts can end up not reporting as expected — meaning you make twelve months of perfect payments and have nothing to show for it. Where that happens, a manual certified request to each of the three bureaus (Experian, Equifax, TransUnion) may be needed to associate the records properly. Confirm the present state of this before relying on it either way.

Second — and this matters if you're planning around American Express Global Transfer: practitioner reporting in 2026 indicates that a US Amex card opened via Global Transfer without a US tax ID may build history internally with Amex but not report to the three credit bureaus, and that an ITIN may not be attachable to that account afterward. If that's accurate, the sequence matters enormously: getting your ITIN before the Global Transfer application, rather than after, could be the difference between a year of credit history and a year of nothing.

One additional rule that affects most markets: Global Transfer requires a consumer card issued directly by American Express — not a corporate card, and not an Amex-branded card issued by a local bank under licence (a GNS arrangement). Kenya and Nigeria are examples where Amex cards exist but are bank-issued and therefore excluded. Check the back of your card: it should say issued by American Express, not by a local bank.

We flag this as [VERIFY CURRENT — confirm directly with American Express] rather than stating it as fact, because it's exactly the kind of provider-policy detail that changes and that nobody should act on from a blog post. But if you're planning a credit build around Global Transfer, ask the question before you apply, not after.

And to be blunt about the surrounding noise: nobody can guarantee you a credit card, a credit limit, or a score. Anyone advertising "guaranteed approval with an ITIN," "$50k in credit in 30 days," or an "aged credit file" is selling you something that either doesn't work or isn't legal. An ITIN is a tax number. Treat any claim beyond that with suspicion.

ITINs and banking

A recurring question: "will an ITIN get me a US bank account?"

Sometimes it helps. It is rarely the deciding factor.

Most US fintechs serving foreign-owned companies (Mercury, Relay and similar) underwrite the business, and the questions that actually determine approval are: is the entity real and in good standing, is the business model something they serve, is the address acceptable, is the owner verifiable, and is the country on their eligible list. An ITIN doesn't override any of those.

Traditional banks are a different conversation — many require in-person account opening for foreign owners, and their taxpayer-ID requirements vary. Some will want an ITIN; some want the owner physically present; some want both.

Check the current position for every named provider — country eligibility and documentation requirements in this space change several times a year.

The honest summary: get an ITIN if you have a tax reason for one. Don't buy one as a banking key and expect it to open doors by itself.

The rejections we see most

If you're doing this yourself, these are the avoidable failures, in rough order of frequency:

1. Reason code doesn't match the documentation. The most common single cause.
2. No return attached and no valid exception documented. People assume they can apply standalone.
3. Name inconsistency. Passport says one thing, form says another — a middle name included here and omitted there is enough.
4. Insufficient identity documents. Something other than a passport was used, and the combination didn't satisfy the requirement.
5. Uncertified copies. Notarized is not the same as certified by the issuing agency, and neither is the same as CAA-certified.
6. Expired supporting documents.
7. Incomplete address information, particularly where the foreign address format doesn't fit the form's expectations.

Each rejection costs you a full processing cycle. That's the real argument for getting it right the first time, whoever prepares it.

Country-specific notes

The core process is identical everywhere, but practical friction varies:

• Countries where the passport office won't issue certified copies — CAA route becomes effectively the only sensible option.
• Countries with slow or unreliable international post — mailing an original passport carries real risk, not theoretical risk.
• Countries with treaty benefits worth claiming — the treaty reason code path may apply; confirm your country's treaty status and the specific article you're claiming under.
• Countries with capital controls — paying for a US service is its own question, separate from the ITIN process. We cover that in our country guides, and the short version is: pay through your bank, documented, in your own name, within your country's legal allowances. We cover the payment mechanics in our guide to paying a US company from your country. Never through an "agent" offering a better rate.

Should you do this yourself?

Genuinely: yes, if your situation is simple and you have patience.

Do it yourself if you have a clear, standard reason code, a valid passport, a straightforward tax situation, and either a spare passport or a functioning certified-copy route at home. The forms are free. The IRS instructions, while dense, are complete. Plenty of people complete a W-7 successfully with no help at all.

Get help if any of these apply: you're unsure which reason code fits, you're applying under an exception, you can't part with your passport and have no local certification route, you've already been rejected once, or your situation involves a partnership, treaty claim, or property sale.

And don't get an ITIN at all if you've read this far and realised you don't have a tax reason for one. That's a legitimate outcome of reading this page, and we'd count it as the page doing its job.

What we do, if you want it

We prepare and submit W-7 applications through a Certifying Acceptance Agent, which means your passport stays with you. We handle the reason-code selection and documentation package, and we follow up with the IRS. Our ITIN service is priced publicly on our pricing page, alongside everything else we do.

We can't promise you a date, because the IRS controls the calendar and anyone who tells you otherwise is guessing.

If you're not sure whether you need one, message us and ask — we'll tell you if the answer is no.

Keep reading

Once you have your ITIN, the next step is usually opening a US business bank account — our guide covers the top rejection causes and how to avoid them. If you prefer a managed approach, the Keystone Bridge bank account setup service handles the provider introduction and document preparation. If you haven't formed your US entity yet, our guide to choosing the best US state for your LLC covers the Delaware vs Wyoming decision. And for your annual US filing obligations, read our Form 5472 guide — the $25,000 penalty for non-filing applies regardless of whether your LLC had income.

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