Which IRS fax number to use
The IRS chooses the fax line by where the business is based, not by where you happen to be when you send the fax. The Instructions for Form SS-4 list these numbers:
| Your situation | Fax number |
|---|---|
| No legal residence, principal place of business, or principal office or agency in a U.S. state or D.C., faxing from abroad | +1 304-707-9471 |
| Same situation, faxing from inside the U.S. | 855-215-1627 |
| Principal place of business, office or agency in a U.S. state or D.C. | 855-641-6935 |
Most foreign-owned LLCs are run by their owners from outside the U.S., so the international line usually applies. If your LLC has a U.S. office or is managed from the U.S., the domestic line may apply instead. If your only U.S. presence is a registered agent, or you’re unsure, ask a tax professional before you send. The IRS says these numbers may change without notice and can only be used to apply for an EIN.
Check these before you send
- Every required line is complete. Our Form SS-4 line-by-line guide covers what a foreign applicant enters on each line, including “Foreign” on line 7b when the responsible party has no SSN or ITIN.
- Your own fax number is on the form. The applicant’s fax number box at the bottom of the form is how the IRS faxes the EIN back. Include the country code.
- The form is signed and dated by someone the IRS accepts as a signer (see below).
- The pages are legible. Send a clean, straight scan at normal resolution, with the whole form on the page.
- The LLC already exists. An LLC or corporation should be formed with its state before applying, or the EIN application may be delayed.
Who signs the SS-4
The IRS lists who may sign for each kind of applicant. For an LLC that’s a responsible and duly authorized member or officer who knows the company’s affairs, and the instructions add that foreign applicants may have any duly authorized person sign. For a single-member LLC that’s normally the owner. Write the signer’s name and title in the space next to the signature, for example “Sole member”.
If someone else applies for you
You can authorize a third-party designee — an individual who receives the EIN and answers questions about the form — in the designee section of the SS-4. The IRS rules are strict:
- The designee section only counts if the signature area is also completed.
- The designee’s authority ends once the EIN is assigned and released to them.
- The designee gets the EIN by the method they used to apply, but the EIN notice is still mailed to you, at the address on the form.
Our EIN application service prepares the form for you to review and sign, then sends it to the IRS and follows up until your EIN is issued.
After you fax
Keep the transmission report from your fax service as proof of the date you sent it. If the application is complete, the IRS generally faxes the EIN back within 4 business days, and later mails the CP 575 confirmation notice to the address on the SS-4. That letter is your long-term proof of the EIN — see CP 575 vs. Letter 147C.
In practice, replies often take longer than the IRS target. Our guide to how long an EIN takes shows what to expect, and EIN delay help covers what to do when nothing arrives. Don’t simply send the same form again: a second application for the same entity risks a second EIN.
The other two routes
- Phone. If the business has no legal residence, principal place of business, or principal office or agency in the U.S. or its territories, you may call +1 267-941-1099 (not toll-free), Monday–Friday, 6 a.m. to 11 p.m. Eastern time. The EIN can be issued during the call.
- Mail. International applications go to Internal Revenue Service, Attn: EIN International Operation, Cincinnati, OH 45999. The IRS estimate is about 4 weeks.