Fax Form SS-4 to the IRS: Get Your EIN in 4 Days

IRS Fax Numbers for Form SS-4

• Domestic (50 states + DC): (855) 641-6935
• International from within the US: (855) 215-1627
• International from outside the US: (304) 707-9471

The Fax-TIN service operates 24/7, 365 days a year. Form SS-4 has a field for your return fax number in the signature block, labeled "Applicant's fax number." Fill it in, and put the same number on your cover sheet, so the IRS can fax your EIN back to you.

Who Needs to Fax SS-4?

The IRS online EIN tool works for most US applicants — but not everyone. You'll need to fax if: you're a non-US resident without an SSN or ITIN, you hit a Reference Number error (101, 105, 106, 107, or 115) on the online tool, or you need to include supporting documents like Articles of Organization. International founders forming US LLCs through Stripe Atlas, Amazon, or Shopify commonly use the fax path.

What the IRS Sends Back

After receiving your faxed SS-4, the IRS faxes back a cover sheet with your assigned EIN within approximately 4 business days. This is NOT the CP 575 confirmation letter — that arrives separately by mail in 4-6 weeks. Keep both: the fax-back for immediate use (opening bank accounts, starting payroll) and the CP 575 for permanent records. If the CP 575 never arrives, you can request a Letter 147C replacement by phone.

How to Fax Form SS-4 with FaxTerra

Download Form SS-4 from IRS.gov, fill it out completely, and save as a PDF. Upload it here, enter (855) 641-6935 (or the international number), and send. FaxTerra transmits at high resolution automatically, so your form goes through clear and legible — there are no settings to adjust. Before you send, put your FaxTerra number in the "Applicant's fax number" field in the form's signature block, and add it to a cover sheet as well. That is how the IRS knows where to fax your EIN back. Your delivery confirmation is your proof of filing.

Tips for Success

Fill out every field — incomplete forms are rejected without notice. One field is easy to miss: "Applicant's fax number" in the signature block. Without it the IRS has nowhere to fax your EIN back, and you are left calling to chase it. Double-check the Responsible Party's SSN or ITIN (Line 7b). For foreign applicants without an SSN, write "Foreign person — no SSN or ITIN" in the SSN field. Start from a sharp, legible scan or photo — FaxTerra transmits at high resolution automatically, so a clean source document is all you need. If the fax line is busy (common during business hours), try early morning Eastern time or weekends — the Fax-TIN service runs 24/7. Non-US founders should also read the EIN for Non-US Residents guide for international-specific timelines and the phone-followup playbook. Once you have your EIN, you may also need to request a 147C verification letter — banks require official IRS proof of your EIN before they will open a business account. For the broader picture of what the IRS accepts by fax, see How to Fax the IRS.