How to Fax Your SS-4 to the IRS

Quick Summary

Here's what you need to do:

Print your SS-4 form
Sign and date Line 18
Fax to +1 304-707-9471 (international) or 855-641-6935 (US)
Save your fax confirmation
Wait 4-6 weeks for your EIN letter

Before You Fax: Checklist

Complete these steps before sending:

Print on standard white paper (8.5" x 11")
Verify your LLC name matches your formation documents exactly
Sign Line 18 with blue or black ink
Add today's date next to your signature
Keep the signed original for your records

IRS Fax Numbers

Use the correct number based on your location:

International applicants: +1 304-707-9471
US-based applicants: 855-641-6935 (toll-free)
Lines are available 24/7
Best times: Before 9 AM or after 6 PM Eastern (fewer busy signals)

Online Fax Services

No fax machine? Use an online service:

FaxZero (faxzero.com): Up to 5 free faxes/day
FAX.PLUS (fax.plus): 10 free pages for new users, mobile app available
HelloFax (hellofax.com): 5 free pages when you sign up
eFax (efax.com): Paid service, most reliable for business use

After You Fax

What to expect:

IRS processes faxed SS-4s in 4-6 weeks
You'll receive a CP 575 confirmation letter by mail with your EIN
The letter is mailed to your LLC's US address (your registered agent)
Your registered agent will forward the letter to you or notify you
No email or online confirmation — the mailed letter is your only notification
Keep your CP 575 safe — banks and institutions require it to verify your EIN

Common Mistakes

Avoid these errors that cause rejections:

Missing signature on Line 18 (most common rejection reason)
Using the wrong fax number (international vs US)
Faxing multiple times (creates duplicate EIN problems)
Using correction fluid (reprint instead)
Poor print quality (illegible forms get rejected)

Frequently Asked Questions

How long until I receive my EIN?

4-6 weeks after the IRS receives your fax. There's no way to expedite this when faxing yourself. If you need it faster, our Express (3 days) or Priority (1 day) plans handle everything for you.

What if my fax doesn't go through?

IRS fax lines get busy. Wait 15-20 minutes and try again. Early morning or late evening Eastern time usually has fewer busy signals.

Can I use my EIN before getting the CP 575 letter?

Technically yes, but you won't know your EIN until the letter arrives. Most banks require the CP 575 letter to open accounts anyway.

I made a mistake on the form. What do I do?

Don't use white-out. Print a fresh copy, make the correction, sign it, and fax the corrected version. If you already sent an incorrect form, wait for the IRS response.