Where to Send Your SS-4 Form: Mail, Fax, or Online from Abroad

You can send Form SS-4 to the IRS in one of three ways: apply online for an immediate EIN, fax the completed form to the IRS for a response in about four business days, or mail it to the IRS EIN Operation in Cincinnati and wait roughly four weeks. Where exactly to send it depends on whether your principal place of business is in the United States, in a U.S. territory, or abroad. All three methods are free directly through the IRS.¹

Apply Online for an Immediate EIN

The IRS online EIN assistant is the fastest route and issues the number as soon as the application is approved. It replaces the paper form with an interview-style questionnaire covering the same information. There is no fee; any third-party site charging for an EIN is not the IRS.¹

To use it, your principal place of business must be in the United States or a U.S. territory, and the responsible party must have a Social Security number or ITIN. Only one EIN can be issued per responsible party per day. The session times out after 15 minutes of inactivity, so complete it in one sitting.¹

The assistant is available Monday through Friday, 6:00 a.m. to 1:00 a.m. the next day; Saturdays, 6:00 a.m. to 9:00 p.m.; and Sundays, 6:00 p.m. to midnight, Eastern Time. Print the EIN confirmation letter the moment it appears on screen. If you lose it, replacing it means calling the IRS business line and requesting a Letter 147C.²

Fax Numbers for Form SS-4

Faxing a completed SS-4 is the next fastest option. The IRS generally faxes the EIN back within four business days, so include a return fax number on the form.³

Principal place of business in one of the 50 states or the District of Columbia: 855-641-6935.³
Principal place of business in a U.S. territory, or international applicant faxing from inside the United States: 855-215-1627.⁴
Faxing from outside the United States: 304-707-9471.⁴

Mailing Addresses for Form SS-4

Mail is the slowest route. Expect about four weeks for the IRS to process the form and mail the EIN back, so file well ahead of any deadline that needs the number. Sign and date the form before sending.³

If your principal place of business is in one of the 50 states or the District of Columbia, mail the form to:

Internal Revenue Service
Attn: EIN Operation
Cincinnati, OH 45999³

If you’re in a U.S. territory or outside the United States, mail it to a different unit at the same facility:

Internal Revenue Service
Attn: EIN International Operation
Cincinnati, OH 45999⁴

Applying from Outside the United States

If you have no legal residence, principal office, or place of business in the United States or its territories, the online application is not available to you. You can apply by phone, fax, or mail.⁴

The phone option is reserved for international applicants. Call 267-941-1099 (not toll-free), Monday through Friday, 6:00 a.m. to 11:00 p.m. Eastern Time. The caller must be authorized to receive the EIN and able to answer questions about the SS-4.²

For fax, use 304-707-9471 from abroad or 855-215-1627 from within the United States. For mail, use the EIN International Operation address in Cincinnati listed above.²

If a Return or Deposit Is Due Before Your EIN Arrives

When a filing deadline hits before the EIN has been issued, write “Applied For” and the date you applied in the space where the EIN would normally go. Do not use your Social Security number in the EIN field on a business return.⁴

For a tax deposit due before the EIN is assigned, send payment to the IRS service center for your filing area. Make the check payable to “United States Treasury” and include the name as shown on the SS-4, your address, the type of tax, the period covered, and the date you applied for the EIN.⁴

1
Internal Revenue Service. Get an Employer Identification Number
2
Internal Revenue Service. Employer Identification Number
3
Internal Revenue Service. Instructions for Form SS-4 (12/2025)
4
Internal Revenue Service. Instructions for Form SS-4 (Rev. December 2025)