In the sequence of setting up a branch, EIN is the smallest-looking link that blocks the most: without EIN, you cannot open a bank account, run payroll, file taxes — your entire operational plan stands waiting for nine digits. For US citizens with an SSN, those nine digits arrive online in ten minutes; for Vietnamese business owners without an SSN or ITIN, the online door closes — and the alternative route goes through paper forms, fax machines, and weeks of waiting.
Nothing is inherently difficult — only many details easy to get wrong, and each mistake costs you weeks. This article covers the entire route: filling SS-4 correctly for a foreign parent company's subsidiary structure, choosing the submission channel, real timelines to schedule around, and a checklist of errors that cause rejections — compiled from those who went before.
What is EIN and why you need it before everything else
EIN (Employer Identification Number) is the federal tax ID for a legal entity — used for all IRS communication and is the identifier that banks, partners, and payroll systems demand first. The name is misleading: not just companies with employees need it — every corporation needs an EIN immediately after formation.
In the sequence of your timeline, EIN sits at a critical junction: after articles of incorporation, before bank accounts — and bank accounts come before capital infusion, capital before leases and hiring. That is why scheduling EIN application as early as possible in your US-side tasks is essential: every week delayed here is a week delayed down the entire chain.
Why you cannot use the online channel: the responsible party bottleneck
The IRS online EIN application system requires the responsible party — the individual controlling the legal entity — to have a valid SSN or ITIN for authentication. A Vietnamese business owner with no prior US work history has neither: the online channel rejects you at the authentication step, with no valid workaround on this channel.
Be cautious about offers to use someone else's SSN (an acquaintance, a service) to stand as responsible party for speed: the responsible party, by IRS definition, must be the person actually controlling the entity — naming someone who does not control it is a false statement to the federal tax authority, and changing it later still requires procedures. The slow but correct path: Form SS-4 with the responsible party as the actual owner, the SSN line filled per guidance for non-US persons.
Filling Form SS-4 correctly for your structure: the deciding lines
SS-4 is one page but several lines determine whether your file moves or gets rejected: the legal entity name must match your articles exactly (every period in Inc.); the mailing address must be reliable in the US (office address if you have one, or registered agent/attorney address per agreement); responsible party is the actual owner with the SSN line marked Foreign per standard guidance for those without SSN/ITIN; entity type marked as corporation with state of formation; reason for application marked as new business startup.
Signer: the responsible party themselves, or a third party authorized via the Third Party Designee section — standard structure when an attorney or CPA represents you and tracks the file (they receive information and handle issues directly with the IRS). For someone doing this from Vietnam, designee is the most worth considering: it turns time-zone-shifted long-distance calls into the work of someone on-site.
Submission channels and real timelines: fax is the main route
Two channels for files that cannot submit online: fax (the main route — significantly faster) and postal mail (slow, only when no other option). Fax today does not require a fax machine: electronic fax services send from Vietnam; the fax number for SS-4 for international entities per current IRS guidance — verify on the official IRS page at the time of submission since these endpoints can change.
Real timelines to schedule around: the fax route takes weeks (varies by season — tax season is slower), the mail route takes months or more. There is one faster route for certain international structures: calling the IRS international filer phone line directly to be assigned an EIN over the phone — real-world experience varies (long hold times, requires the caller to have sufficient authority), but for those in a hurry, worth trying in parallel.
While waiting and after you receive it: using EIN on the right schedule
During the waiting weeks: do not let your task chain sit idle — prepare bank account documents in advance (covered in a separate article), negotiate leases to the signing-ready stage, finalize your business plan. When the EIN arrives (via fax response or confirmation letter CP 575), keep the confirmation document carefully — banks typically demand this specific document, not just the number.
After you receive it: use one consistent version of name + EIN + address on all documents (bank, tax, contracts) — name format inconsistencies across different places are a classic source of headaches in later years. And if your company later changes address or responsible party: there is a separate IRS form to update, add it to your compliance calendar so you do not forget.
Error checklist that causes file rejection: lessons from those before you
- Legal entity name differs from articles by one character, or you use a trade name instead of the registered name.
- Responsible party line lists a service or acquaintance instead of the actual owner, or left blank instead of correctly marked Foreign.
- Mailing address is unreliable — lost confirmation letter means lost file trail.
- Fax loses a page, signature is blurry — use an electronic fax service with transmission confirmation.
- Impatience causes you to resubmit when the first submission is still processing — creates duplicate files, adds weeks of confusion.
Core principle: submit once, correctly, then wait patiently on one channel — and if you use an attorney or CPA as designee from the start, nearly this entire checklist disappears from your life.
Note: this article is informational reference, not legal or immigration advice. Visa-L1.com is a business consulting and operations firm, not a law firm; all L-1A and EB-1C legal documents are prepared and filed directly by US-licensed immigration attorneys. Government fees and USCIS policy may change; verify at the time of filing.
Frequently Asked Questions
How long does it take to get an EIN without an SSN?
The fax route — the main channel for international files — takes weeks, varying by season; the mail route is significantly slower. You can try the IRS international phone line in parallel (some structures can be assigned an EIN by phone). Since it is the bottleneck for bank accounts and everything after, submit Form SS-4 as soon as possible right after you have your articles of incorporation.
Can I ask someone with an SSN to apply for the EIN faster?
Not recommended: the responsible party, by IRS definition, must be the person actually controlling the entity — naming someone who does not control it is a false statement to the federal tax authority and still requires procedures to change later. The correct path: SS-4 with yourself as responsible party (SSN line marked Foreign per standard guidance), optionally with a Third Party Designee who is an attorney or CPA to track and handle issues directly with the IRS.
Do I need an EIN before opening a bank account?
Yes — EIN is the document banks demand first, typically with the actual IRS confirmation document (letter CP 575 or fax response) not just the number. So the correct sequence is: articles of incorporation → submit SS-4 immediately → while waiting, prepare bank documents → when EIN arrives, schedule the bank account opening right away.
I submitted SS-4 but it has been too long with no response — what do I do?
Do not resubmit immediately — duplicate files create additional weeks of confusion. The correct approach: after the normal processing period, call the IRS international filer line (or have your designee call) to check status by legal entity name; only resubmit if the file is actually lost, per IRS guidance in that call. This is why a reliable mailing address and an on-site designee are worth the investment.
