IRS EIN fax number (Form SS-4)
The IRS fax number for an EIN application on Form SS-4 is 855-641-6935 if your business is in one of the 50 states or the District of Columbia, and 855-215-1627 if it is not. Both are below with the mailing address for each, the official page they came from and the date we last checked it.
Business in a state or the District of Columbia
855-641-6935
this week · 10-29-2026 Official website Fax this number
Use this number if the legal residence, principal place of business, or principal office or agency is in one of the 50 states or the District of Columbia.
Business outside the states and DC
855-215-1627
this week · 10-29-2026 Official website Fax this number
Use this number if there is no legal residence, principal place of business, or principal office or agency in any state or the District of Columbia, for example a business in a U.S. territory or abroad. The IRS gives a separate number for faxes sent from outside the United States. A ProntoFax fax goes out from the United States, so this is the one for it.
ProntoFax is an independent fax service. We are not affiliated with, endorsed by, or connected to the Internal Revenue Service.
Where to mail Form SS-4
If you mail the form instead, the IRS sends the EIN by mail in about 4 weeks. The address follows the same split as the fax numbers. Send the form one way only.
Business in a state or the District of Columbia
Internal Revenue Service
Attn: EIN Operation
Cincinnati, OH 45999
Mail Form SS-4 here if the legal residence, principal place of business, or principal office or agency is in one of the 50 states or the District of Columbia.
Fax: 855-641-6935
this week · 10-29-2026
Business outside the states and DC
Internal Revenue Service
Attn: EIN International Operation
Cincinnati, OH 45999
Mail Form SS-4 here if there is no legal residence, principal place of business, or principal office or agency in any state or the District of Columbia.
Fax: 855-215-1627
this week · 10-29-2026
The IRS faxes your EIN back
When you apply by fax, the IRS faxes the EIN back to the fax number you write on the form, generally within 4 business days. The instructions say to be sure you give one.
ProntoFax sends faxes. It cannot receive them, so the return number has to be a fax line of your own, or one at an office that will pass the EIN on to you. If the form has no return fax number, the IRS writes to you instead, which takes longer.
If your business is in the United States or a U.S. territory, the IRS recommends applying online, where the EIN is issued at the end of the session. Fax is the route for when you cannot apply online, for example when the responsible party has no Social Security number or individual taxpayer identification number, or when the business is abroad.
One EIN, one way to apply
The IRS issues one EIN per responsible party per day, however you apply. Use one method for each business: faxing and also mailing, or faxing and also applying online, can leave the business with two EINs.
How we verify fax numbers
Every number on this page was published by the agency itself. The two columns beside it say when that number was last confirmed, and what confirmed it.
The Verified by column says which of these it was:
Official website the agency publishes this number. The date is the day we read it from their page or their published file.
ProntoFax user a fax sent through ProntoFax reached this number and the receiving machine confirmed it. The date is the most recent delivery.
ProntoFax automation we called the number and heard a fax tone answer. Nothing is sent and the call ends as soon as the line answers.
Needs verification recent attempts to this number did not go through. It stays listed because the agency still publishes it, but check it against your own letter before you send.
The date is colored by how long ago it was:
Within 90 days 91 to 270 days Over 270 days
We never add a number because someone faxed it. A number appears here only if the agency published it. A delivered fax can confirm a number, but it can never create one.
What goes to these numbers
The instructions say these numbers can only be used to apply for an EIN:
- Form SS-4, Application for Employer Identification Number, signed
- Nothing else. Other IRS forms have their own numbers and addresses.
Before you send
The IRS asks for no cover sheet on a faxed Form SS-4. If you add one, include:
- The legal name of the business exactly as it appears on line 1
- The name of the responsible party
- A daytime phone number
- The number of pages, including the cover sheet
Write a return fax number in the box the form gives for it, at the bottom of the form, not only on a cover sheet. That is the number the IRS faxes the EIN to.
Keep your delivery confirmation. It is your record of when the application reached the IRS.
The IRS says these numbers may change without notice. We check them on its own page, and the date we last did is shown beside each one.
Send it from your phone
Photograph each page of the signed form with your phone camera, or upload a PDF.
Add a cover sheet with the business name and a phone number, if you want one.
Check every page in the preview before anything goes out.
Enter the number for your business from above. We check that the line can receive.
Pay $2.99 and watch it send. If it is not delivered, you are not charged.
Pay only when delivery is confirmed
Why ProntoFax
- Flat $2.99 per delivered fax, no subscription
- No account or sign-up required
- We validate the fax line before you pay
- No charge if your fax does not go through
- Email receipt with delivery time, page count, and a link to view the document you sent
Questions about faxing Form SS-4
Can I get an EIN by fax?
Yes. The IRS takes Form SS-4 by fax and faxes the EIN back, generally within 4 business days, to the fax number you put on the form.
Will ProntoFax receive my EIN?
No. ProntoFax sends faxes and cannot receive them. Give the IRS a fax number of your own, or one at an office that will pass the EIN on. Without a return number, the IRS writes to you instead, which takes longer.
Which of the two numbers do I use?
The first if the business has its legal residence, principal place of business, or principal office or agency in one of the 50 states or the District of Columbia. The second if it has none of those in any state, for example a business in a U.S. territory or abroad.
Should I apply online instead?
If you can, yes. The IRS recommends the online application for businesses in the United States and its territories, and it issues the EIN at the end of the session. Fax is for when you cannot use it, for example when the responsible party has no Social Security number or individual taxpayer identification number.
Is the EIN fax number the same as the Form 2553 number?
No. Form 2553, the S corporation election, has its own two numbers split by state. The SS-4 numbers are only for applying for an EIN.
How much does it cost?
$2.99 for one fax of up to 25 pages. No subscription and no account. Your card is held and only charged once delivery is confirmed.