Fax Form SS-4 to the IRS for an EIN
To apply for an EIN by fax, send Form SS-4 to 855-641-6935 if the applicant’s legal residence, principal place of business or principal office is in one of the 50 states or the District of Columbia. Otherwise fax it to 855-215-1627, or to 304-707-9471 when faxing from outside the US. The IRS faxes the EIN back in about 4 business days if you give a fax number that can receive; without one, it comes by mail. Applicants in the US usually get an EIN fastest online.
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How to fax Form SS-4
- 01
Check whether online is faster
If the business is in the US, the IRS’s online application gives the EIN right away. Fax suits applicants who can’t use it or prefer paper.
- 02
Fill in and sign
Complete Form SS-4; the IRS says the fillable PDF from irs.gov is fine for faxing. The right person signs: the owner, a principal officer, a partner or the fiduciary.
- 03
Fax it once
Send it to the number for your location. Apply one way only: a second application by mail or online can create a duplicate EIN.
- 04
Watch for the reply
With a fax number that receives, the EIN comes back in about 4 business days. Without one, watch your mail.
At a glance
- 50 states and DC
- 855-641-6935
- Anywhere else, faxing from the US
- 855-215-1627
- Anywhere else, faxing from abroad
- 304-707-9471
- EIN by fax
- About 4 business days, to the fax number you give
- FaxJet price
- $2.99 up to 10 pages
Sending Form SS-4
IRS fax numbers for Form SS-4
The number depends on where the applicant is based, and for applicants outside the 50 states and DC, on where you fax from.
| Applicant | Fax number |
|---|---|
| Legal residence, principal place of business or principal office in one of the 50 states or the District of Columbia | 855-641-6935 |
| Anywhere else (a US territory or another country), faxing from inside the US | 855-215-1627 |
| Anywhere else, faxing from outside the US | 304-707-9471 |
From the IRS instructions for Form SS-4 (December 2025, last reviewed April 30, 2026) and its Where to file page, checked October 10, 2026. The IRS says these numbers may change without notice.
Getting your EIN back
If you enter a fax number on the form, the IRS faxes back a cover sheet with the EIN, generally within 4 business days. It no longer returns the SS-4 itself with the EIN written on it.
FaxJet’s website sends faxes but can’t receive them, so it can’t be the return number. Without a fax number of your own, the EIN comes by mail, which is slower; if the business is in the US, the online application is faster still. If a third party designee applies for you, the designee gets the EIN the same way they applied, and the EIN notice is mailed to the business.
Mistakes that slow an EIN down
From the IRS instructions for Form SS-4:
- Applying more than one way for the same business, which can create two EINs.
- Applying for more than one EIN for the same responsible party on the same day.
- A sole proprietor filing more than one SS-4; one is usually enough.
- Putting an SSN where the EIN goes on a return while you wait.
- Using characters other than letters, numbers, hyphens and ampersands in the business name.
After you send it
Form SS-4 carries the responsible party’s SSN or ITIN. FaxJet keeps your document until you delete it, so once the receipt shows the fax was delivered, delete it from the tracking page. The guide to sending a fax from a computer shows each step of the sender.
Questions
How do I get the EIN back if I fax from a website?
A web sender like FaxJet’s sends but can’t receive, so it can’t be your return fax number. Enter a fax number you can receive on, if you have one; the FaxJet iPhone app’s Pro plan includes one. Without a fax number, expect the EIN by mail, which takes longer.
Is the IRS fax line open on weekends?
Yes. The IRS says the Fax-TIN line is available 24 hours a day, 7 days a week.
Can I fax other forms to these numbers?
No. The IRS says the Fax-TIN numbers can only be used to apply for an EIN.
Who signs Form SS-4?
The owner for a sole proprietorship, a principal officer for a corporation, a responsible and authorized member or officer for a partnership or other organization, and the fiduciary for a trust or estate. A third party designee can apply for you if the designee section is filled in.
Can I apply by phone instead?
Only if the business is outside the US: international applicants can call 267-941-1099. The IRS no longer issues EINs by phone to applicants in the US.
What if I need the EIN before it arrives?
The IRS says to write “Applied For” and the date where the EIN goes on a return that is due, and never to put an SSN in its place.