The IRS gives you four ways to apply for an Employer Identification Number: online, by phone, by fax, and by mail. If you have a US Social Security Number, the online form takes about ten minutes and issues the number instantly. If you do not — which is the position most founders outside the US are in — the online tool is off-limits, and you are routed to the other three.
They are not equally fast, equally reliable, or equally forgiving of mistakes, and which one actually works for you often depends on details nobody explains until you have already wasted a submission. This article compares the three from-abroad-eligible channels directly. Applying for an EIN by fax is usually the fastest route from abroad, but phone and mail each have a place.
Why the online EIN application does not work from abroad
The IRS's online EIN assistant requires the responsible party to have a Social Security Number or Individual Taxpayer Identification Number entered at the start of the session, and it will not proceed without one. This is a hard technical restriction built into the tool, not a policy you can request an exception to. Non-resident founders without an SSN or ITIN are automatically pushed to Form SS-4 submitted by phone, fax, or mail instead, which is why the comparison in this article matters: for this specific audience, there is no fast default option, only three slower ones with different trade-offs.
Option one: applying by phone
The IRS operates a dedicated line for international applicants — currently 267-941-1099 — staffed during US business hours and not toll-free from outside the US. This is the fastest of the three non-online routes when it works, because a successful call ends with an EIN issued verbally on the same call, which the assistor then confirms in writing afterwards.
The practical problems are real, though. Hold times can run from a few minutes to well over an hour depending on the time of day and season — tax filing season in particular gets far busier. You are calling a US number from a landline or mobile at international rates unless you use an internet calling service, and the call itself can take 20–45 minutes once connected, since the assistor walks through the SS-4 fields verbally and needs clear, correct answers to each one.
If your entity structure is anything other than the most standard single-member LLC, or if your name has characters or a format the assistor struggles to enter into their system, phone applications are also the channel most likely to hit an unexpected snag mid-call.
Option two: applying for an EIN by fax
Faxing a completed Form SS-4 to the IRS is, somewhat surprisingly for 2026, often the most reliable channel for international applicants. The number for international filers is 304-707-9471. Turnaround is typically 4 business days if you provide a return fax number, though it can run longer during peak periods.
The advantage of fax over phone is that there is no live conversation to go wrong — you fill in the form carefully in advance, at your own pace, and submit it once. The advantage over mail is speed: days rather than weeks. The disadvantage is that most founders outside the US do not own a fax machine, which makes this sound like a dead channel until you know that free online fax-to-email services exist specifically for this kind of one-off document, letting you send a fax from a PDF without any physical hardware.
Search for a reputable free or low-cost internet fax service, confirm it actually transmits to a real fax number rather than just emailing a PDF, and keep the transmission confirmation — it is your only proof of submission if anything goes missing on the IRS side.
Option three: applying by mail
Mail is the slowest channel by a wide margin. The IRS's stated processing time for mailed SS-4 forms from international applicants is around 4–5 weeks under normal conditions, and it has stretched to two months or more during periods of high volume or IRS staffing disruption. The mailing address for international applicants is the IRS Operations centre in Cincinnati, Ohio — check the current SS-4 instructions before sending, since IRS mailing addresses do occasionally change.
Mail's only real advantage is that it requires nothing beyond a working postal service and does not depend on getting through on a phone line or finding a working fax gateway. If your timeline has real slack — you are not waiting on the EIN to open a bank account or apply for a specific programme with a deadline — mail is a low-effort, zero-cost, "set it and forget it" option. It is a poor choice if you need the number within a month.
Side-by-side comparison
| Channel | Typical turnaround | Cost | Main risk | Best for |
|---|---|---|---|---|
| Phone | Same call, if it connects | International call charges | Long hold times; live errors mid-call | Founders who need the number fastest and can tolerate a wait on hold |
| Fax | ~4 business days | Free–low cost via online fax services | Confirming the receiving number and getting proof of transmission | Most founders — best balance of speed and reliability |
| 4–8+ weeks | Postage only | Long unpredictable wait; harder to track | Founders with no deadline pressure |
What to prepare before you use any channel
Every channel starts from the same document — Form SS-4 — so filling it out correctly matters more than which channel you eventually use. Have ready before you start:
- The LLC's exact legal name and formation state, matching your Articles of Organization precisely.
- The responsible party's full legal name, foreign address, and either an SSN, ITIN, or a note that neither applies where the form allows it.
- A clear answer for the entity's principal business activity, described in specific rather than vague terms — "e-commerce retail of apparel" rather than "business."
- The reason for applying (usually "started a new business") and the closing month of your accounting year.
If you already have your LLC approved and are choosing between an EIN and an ITIN as the next step, our guide on EIN or ITIN: which one a foreign founder actually needs is worth reading first, since some founders apply for the wrong one before realising an EIN is usually the one that unblocks banking.
What happens after you have a number
Phone applicants get the EIN verbally, followed by an IRS confirmation letter (the CP 575) by mail some weeks later. Fax and mail applicants receive the CP 575 as their first confirmation, with no earlier verbal number. In all three cases, keep the confirmation letter permanently — banks and payment processors will ask for it, and requesting a replacement later is its own separate process. Our guide on getting an EIN as a non-resident with no SSN covers the full end-to-end process if you have not started yet, and this article assumes you are past that stage and specifically weighing which submission channel to use.
What to do if a submission goes wrong
Fax and mail submissions can occasionally go unacknowledged — no rejection, just silence past the expected turnaround. If more than 60 days have passed with no response to a mailed application, or more than two weeks past the stated turnaround for a fax, calling the international line to check status is reasonable, and you should have your submission date and, for fax, your transmission confirmation ready. If the IRS specifically rejects the form rather than simply not responding, the reasons and fixes are different again — see our companion piece on what to do when the IRS rejects your SS-4 for that scenario specifically.
Timing your call around US business hours
The international EIN line operates roughly 6am to 11pm US Eastern time, Monday to Friday, which means the workable window for a caller in, say, Manila, Lagos, or Dubai falls at an inconvenient local hour more often than not. Founders who have used the line successfully generally report shorter waits calling right at opening time Eastern, since US-based callers who dominate volume tend to call later in their own working day.
If your local time zone puts "6am Eastern" at a reasonable hour for you, that is usually the best slot to try. If it does not, weigh the inconvenience of an odd-hours call against fax's few-day wait — for many founders outside the Americas, fax ends up faster in practice once the awkward call scheduling is factored in, not just on paper.
Whichever time you call, have the SS-4 fully filled in front of you before dialling, not half-completed. Assistors move through the form field by field and expect answers immediately; searching for information mid-call is the most common reason a otherwise-successful call runs long or the assistor asks you to call back once you have gathered what is missing.
A realistic example of how the three channels compare in practice
Consider three founders who all submit a correctly completed SS-4 for a single-member Wyoming LLC on the same Monday. The founder who calls the international line at 6am Eastern gets through after a 25-minute hold and has a verbal EIN by lunchtime their own time, with the CP 575 arriving by post roughly three weeks later. The founder who faxes the form using a free online fax service gets a callback fax with the EIN confirmed on the following Thursday — four business days later — and the CP 575 in the mail a similar three weeks after that.
The founder who posts the form by international courier tracks it arriving in Cincinnati after nine days, and then waits five more weeks for any response at all, receiving the EIN only via the CP 575 itself with no earlier confirmation. All three end up with a valid EIN. The difference is entirely in how long they are blocked from opening a bank account or registering with a payment processor in the meantime — which for most founders is the actual cost of a slow channel, not the EIN itself.
Which channel to actually pick
For most non-resident founders, fax is the best default: materially faster than mail, and without the live-call risk of the phone line. Reserve the phone line for situations where you are already up against a hard deadline and are willing to spend the time on hold, and use mail only when you have no time pressure at all and prefer the simplest possible process. Whichever channel you use, submit one clean, fully completed SS-4 rather than several a few days apart out of impatience — duplicate submissions confuse IRS processing and can delay everyone's, not just your own.
Frequently asked questions
Can I use the online EIN application if I get an ITIN first?
No. The IRS online EIN tool restricts access based on IP address and applicant type in a way that still generally excludes applicants without a US-based mailing address, regardless of holding an ITIN. Phone, fax, and mail remain the practical routes for most founders based outside the US.
Is the IRS international phone line free to call?
No, it is not a toll-free number, and callers from outside the US pay their own international calling rates unless they use an internet-based calling service, which is often cheaper than a standard international call.
Can I fax my SS-4 without owning a fax machine?
Yes. Several online services convert a PDF into a fax transmission for a small fee or for free, sending it to a real fax number without any physical hardware on your end. Confirm the service actually transmits by fax rather than merely emailing the recipient, and keep the transmission report as proof.
Will applying by more than one channel at once speed things up?
No, and it can cause the opposite. Submitting the same application by fax and mail simultaneously risks the IRS processing two SS-4s for the same entity, which can create duplicate EINs or processing delays while the mismatch is resolved. Pick one channel and wait for its normal turnaround before trying another.
If you would rather have this handled for you, our US LLC formation service covers it end to end. For the official position, see IRS: Form SS-4 instructions.