Who this is for: French founders opening a US company, families with US tax obligations, and anyone a US bank or platform just asked for a ‘tax ID’. Three numbers share the same nine-digit shape and get confused daily. They identify different things, come from different agencies, and only one of them is ever a choice.
The confusion is understandable: all three look like 12-3456789. The untangling takes one table:
Question | EIN | ITIN | SSN |
Identifies | A business entity | An individual not eligible for an SSN | An individual authorized to work in the US |
Issued by | IRS | IRS | Social Security Administration |
Who needs it | LLCs, corporations, partnerships, some estates and trusts | Foreign individuals with a US filing or reporting need and no SSN eligibility | US citizens; residents and visa holders with work authorization |
Obtainable from France | Yes, without any US status | Yes, tied to a real tax need | No; requires eligibility, usually via visa status |
Grants the right to work in the US | No | No, explicitly not | It reflects work authorization, it does not create it |
Expires | No | Yes, if unused on a return for three consecutive years | No |
One sentence to keep: the EIN identifies your company, the ITIN or SSN identifies you, and you never choose between ITIN and SSN, eligibility chooses for you. Everything else is procedure.
Table of Contents
The EIN: the number your company cannot live without
The Employer Identification Number is the entity’s federal tax ID, and despite the name, hiring employees is only one of many triggers. Your US LLC or corporation needs one to file its returns, open a bank account, register with payment processors, and simply exist administratively. Two things foreign founders consistently get wrong:
- You do not need an SSN, an ITIN, or any US status to get an EIN. The myth persists because the online application requires an SSN or ITIN. Foreign applicants use the paper-and-phone route instead: Form SS-4, with the responsible party section completed with ‘foreign’ in place of a US number, submitted by fax or processed by phone. Slower than the online path, entirely routine.
- The responsible party must be a real human, not another company, and their name sticks: banks and platforms will match it later. Choose deliberately, typically the founder, and update it when control changes.
If you have seen FEIN on a form and wondered, it is the same number, F for federal; our FEIN vs EIN explainer settles that smaller cousin of today’s comparison.
The ITIN: the misunderstood middle child
The Individual Taxpayer Identification Number exists for exactly one purpose: letting people who cannot have an SSN meet US tax obligations. A French investor with US rental income, a spouse being claimed on a US return, an LLC owner whose share of profits is US-taxable, these are ITIN cases. Three boundaries define it:
- It is need-based, not on-demand. The application (Form W-7) attaches to an actual tax return or fits a listed exception; the IRS does not issue ITINs for someday. The practical corollary: many French founders of US LLCs do not need one at formation, and only acquire the need when profits become US-taxable to them personally, the mechanics we detail in LLC vs C-Corp for foreign founders.
- It confers nothing except tax identity. No work authorization, no Social Security credits, no immigration signal. Banks may accept it for account opening; that is their policy, not its purpose.
- It expires with disuse. Three consecutive years off any return and the number lapses, needing renewal before the next filing. Families rediscover this in the April rush.
Getting one from France, without mailing your passport
The W-7 requires proof of identity, and the default, mailing an original passport to Texas, is nobody’s favorite. Two workarounds exist: a Certifying Acceptance Agent (CAA), who verifies your passport and sends certified copies, and passport certification by the issuing authority. As a firm handling these regularly from Paris, we can say the CAA route is what makes ITIN season civilized.
The SSN: the one you cannot apply your way into
The Social Security Number belongs to a different logic: it is the identifier of people authorized to live and work in the US, issued by the SSA, usually alongside a visa that permits employment. For the readers of this article the rule is short: if you are eligible for an SSN, you must use it, the IRS will not issue an ITIN to someone SSN-eligible; and if you are not eligible, no amount of paperwork makes an SSN available, which is precisely what the ITIN is for. A French employee relocating on a work visa gets an SSN and never thinks about ITINs again; their French spouse without work authorization may be an ITIN case for the joint return; and their US-side company holds an EIN. One household, all three numbers, no overlap.
Common situations, decoded
Situation | What you need | What you do not need |
French founder forms a US LLC, no US-taxable personal income yet | EIN for the LLC | An ITIN, until a personal US filing obligation actually arises |
Same founder, LLC turns profitable with US-source income | EIN + ITIN (with the 1040-NR) | An SSN, no eligibility and no way to opt in |
French investor buys a US rental property | ITIN (income filings), possibly an EIN if holding through an entity | Confusing the property manager: give the right number to the right payer |
Employee relocating to the US on a work visa | SSN, from the SSA after arrival | An ITIN; eligibility for the SSN excludes it |
French parents of a US-person child with US filings | Depends on the return; ITINs where claimed | Panic; the W-7 handles dependents with their own document rules |
A US platform asks your French company for a W-8BEN-E | Usually no US number at all; a foreign TIN often suffices on the form | An EIN just to fill a form; only actual US entities or specific claims require one |
The order of operations for a typical founder
Sequencing saves weeks. Form the entity first, the EIN application needs the legal entity to exist. Apply for the EIN immediately after formation, by fax from France, and expect the number in a few weeks, faster by phone in some seasons. Open banking with the EIN in hand. And leave the ITIN question for tax season, filed with the first return that actually needs it, through a CAA so your passport stays in your pocket. The single most common self-inflicted delay we see is the reverse order: founders chasing an ITIN they do not need yet, while the EIN their bank is waiting for sits unrequested.
The three applications, side by side
Step | EIN | ITIN | SSN |
Form | SS-4 | W-7 | SS-5 |
Where | IRS, by fax or phone for foreign applicants | IRS, with the tax return that creates the need | Social Security office, in person, after US arrival |
Documents | None beyond the form itself | Passport, original or CAA-certified | Passport, visa, work authorization |
From France | Entirely | Entirely, via CAA | Not available; eligibility first |
Typical wait | Days to a few weeks | Weeks to a few months, with the return | Days to weeks, once in the US |
Cost from the IRS/SSA | Free | Free (CAA services are the paid part) | Free |
Note the pattern in the second row: the EIN is a standalone request, the ITIN rides on a tax return, and the SSN rides on immigration status. Which is why the EIN is always the first number a founder obtains, and often the only one for years. It also explains the pricing of the services ecosystem around these numbers: EIN-obtaining services sell speed on something you could do free by fax, while CAA work on ITINs sells something structurally harder to do alone from abroad.
Which number goes on which form
Once the numbers exist, the next confusion is where each one belongs. The payer paperwork sorts cleanly:
Form in front of you | Whose number it wants | Which one |
W-9 | A US person or entity | SSN (individuals) or EIN (entities) |
W-8BEN | A foreign individual receiving US-source income | Foreign tax number usually suffices; ITIN when claiming certain treaty benefits |
W-8BEN-E | A foreign entity | Foreign tax number usually; EIN only in specific cases |
1040-NR | A non-resident filing US taxes | ITIN (or SSN if held) |
5472 / 1120 | The US entity and its foreign owner | EIN for the entity; the owner is identified without needing a US number |
State forms and payroll | The employer | EIN, plus state-level registrations that piggyback on it |
The most expensive confusion in this table is answering a W-8 with a W-9 mindset: a French company that requests an EIN it does not need, to fill a box that wanted its French number, has created a US filing footprint to maintain, for nothing.
Housekeeping: renewals, mismatches and lost numbers
- Lost EIN: it is never reissued and never expires; retrieve it from the CP 575 confirmation letter, old filings, or the IRS by phone with identity verification. Banks lose it more often than founders do.
- Name-number mismatches block bank onboarding and platform verification: the entity name on the SS-4 must match the formation documents to the character, punctuation included. Fixing a mismatch takes an IRS letter and weeks; getting it right takes proofreading.
- ITIN renewals (after the three-year lapse) can be filed without a return, before filing season, which is precisely when to do them: a renewal riding with a return adds its processing time to your refund’s.
- One person, two identities: someone who held an ITIN and later becomes SSN-eligible must stop using the ITIN and notify the IRS so the histories merge. Running both in parallel splits your tax record in two.
The CP 575 letter: the document your bank actually wants
The EIN arrives with a confirmation letter, the CP 575, and founders who treat it as junk mail regret it: US banks, fintechs and payment platforms routinely require the letter itself, not just the number, during onboarding. It is issued once. Lose it and the replacement is a different document, the 147C verification letter, obtained by phone, which most institutions accept but which adds weeks precisely when the account opening was urgent. The routine that spares the pain: the day the EIN arrives, scan the CP 575, store it with the formation documents, and note the exact entity name as the IRS spelled it, because that spelling, not your certificate of formation’s typography, is what every later verification matches against. Ten minutes of filing discipline, several onboarding cycles saved. The same letter also answers the perennial platform question about proof of tax identity: when Stripe, Amazon or a marketplace compliance team asks for documentation of the EIN, the CP 575 or its 147C substitute is the expected artifact, not a screenshot of the number typed somewhere.
Putting it together: the founder timeline with all three numbers
Moment | Number event | Watch out |
Company formed | EIN application by fax, same week | Responsible party named deliberately; CP 575 archived on arrival |
Bank and platforms onboarded | EIN + CP 575 do the work | Name mismatches are the number-one onboarding blocker |
First profitable year with US-taxable income | ITIN via W-7 riding the first 1040-NR, CAA route | Start before filing season; the ITIN wait adds to the return’s |
A move to the US ever happens | SSN replaces the ITIN | Notify the IRS so the two histories merge; retire the ITIN |
Years later, structures multiply | Each entity its own EIN | Holding companies, subsidiaries and even some trusts each need one; numbers are per entity, never shared |
Read as a timeline, the confusion dissolves: the EIN is a formation-week task, the ITIN is a tax-season task, and the SSN is a relocation event. Nothing needs to be done in advance of its moment, and nothing survives being done in the wrong order.
Eighteen months in one family: all three numbers in the wild
A composite that recurs in our files. Month one: a French founder forms a Delaware LLC for a SaaS product; we file the SS-4 by fax, the EIN lands in week three, the CP 575 goes straight into the data room. Month two: US banking opens against the EIN; the founder’s own French numbers satisfy every W-8 the platforms send. Month nine: a US enterprise client pushes the product into real revenue, and the year-end analysis finds ECI; the first 1040-NR goes out in the spring with a W-7 attached through our CAA desk, and the ITIN arrives before summer. Month fourteen: a seed round appears; the LLC converts to a Delaware C-Corp, which in most cases needs its own new EIN, the conversion detail everyone forgets (an 8832 tax election, by contrast, keeps the number). Month eighteen: the founder relocates on an E-2 visa, receives an SSN, and we notify the IRS to merge the ITIN history into it. Five number events, none optional, none simultaneous, and a family that never once stood in line at an IRS office. The sequence is the product; the numbers are just its receipts. And when the second entity arrives, the holding company, the sister LLC for a new product line, the whole cycle reruns in miniature, faster, because the file from the first pass already answers every question the bank will ask.
How Expand CPA fits in
We obtain EINs for French-owned entities and run ITIN applications as part of the first US filing, from Paris, in French, with the CAA passport route. If your structure question is still open, start with LLC vs C-Corp; if the structure exists and the numbers are the blocker, that is a one-week job done right. Talk to us.
Frequently Asked Questions
Can my French company get an EIN without creating a US entity?
Yes. Foreign entities obtain EINs when they need one, for US withholding paperwork, certain treaty claims, or US filing duties, using the same SS-4 route. Needing one is rarer than platforms imply: for most W-8 forms, your French tax number does the job.
How long does each number take?
EIN: near-immediate by phone in favorable seasons, a few weeks by fax. ITIN: counted in weeks to a few months, tied to return processing, CAA filings moving smoothest. SSN: days to weeks after US arrival with work authorization. Plan the EIN before banking, the ITIN before filing season, and the SSN around relocation.
I had an ITIN years ago and moved back to France. Is it still valid?
If it has not appeared on a US return for three consecutive years, it has expired and needs renewal via W-7 before your next filing. Renewals do not require a tax return attached, one of the few W-7 paths that stands alone.
Can I use my EIN instead of an SSN or ITIN for personal matters?
No, and trying is a classic self-inflicted tangle. The EIN identifies the entity, and using it where a personal number belongs, on a personal W-8, a lease application, an investment account, creates records the IRS matching systems cannot reconcile. The reverse error, giving your ITIN for company business, splits the company’s history the same way. The discipline is mechanical: entity paperwork gets the EIN, your paperwork gets your number, and where a form seems to want one you do not have, the answer is almost never to substitute, it is to check whether the form actually requires a US number at all. As the W-8 rows above show, it frequently does not. Five minutes with the form instructions routinely dissolves a request that felt like a blocker, and spares you a number you would then have to maintain.
Related Expand CPA guides
- How to obtain an ITIN, step by step
- FEIN vs EIN: which one does your business need
- LLC vs C-Corp for foreign founders
- LLC for foreigners: the formation guide
Disclaimer: Application procedures and rules verified August 2026 against IRS and SSA sources. Processing times vary by season. General information, not tax or immigration advice.
