How to Fax Form SS-4 (EIN Application) to the IRS

Form SS-4 is the application for an Employer Identification Number (EIN) — needed to open a business bank account, hire employees, or file certain business tax forms. While many applicants use the IRS's online EIN tool, faxing is still the standard method for entities that aren't eligible to apply online, including many international applicants.

Before You Fax

• Include your own return fax number on the form. The IRS sends your EIN back by fax, so if this is missing, you won't receive a response that way.
• The correct submission fax number depends on where the applicant's principal place of business, office, or agency is located — domestic, U.S. territory, or entirely outside the U.S. all route differently.
• Use only one method to apply for your EIN (fax, mail, or online) — applying multiple ways can result in duplicate EINs being issued.

How to Send It Online

1. Complete Form SS-4 from irs.gov, including a return fax number where you can receive your EIN
2. Confirm the correct submission fax number for your location from the current official instructions
3. Save your completed form as a clean PDF
4. Upload it right here on LowFax using the Send a Fax button below, enter the verified fax number, and send
5. Keep your delivery confirmation, and watch for your EIN to arrive by fax within a few business days

Who Typically Uses Fax Instead of the Online Tool

The IRS's online EIN application isn't available to every applicant — for example, entities without a U.S. principal location generally can't use it and need to apply by fax or mail instead. Fax remains significantly faster than mail in these cases.