SS-4 Application for Employer Identification Number (SS-4 form)

irs.gov says to use Form SS-4 to apply for an employer identification number. An EIN is a 9-digit number (for example, 12-3456789) assigned to employers, sole proprietors, corporations, partnerships, estates, trusts and other entities for tax filing and reporting purposes. The instructions say not to use an EIN in place of your social security number or ITIN: an EIN is for your business activities only. The form's page 2, "Do I Need an EIN?", says to file SS-4 if the applicant entity does not already have an EIN but must show one on a return, statement or other document.

The IRS online EIN application is the route the IRS points most applicants to. Its irs.gov page says you can use it if all of these are true: you are a domestic organization formed or created in the United States or U.S. territories; your principal place of business is in the U.S. or U.S. territories; you are the responsible party in control of the entity, or its authorized representative; and you have the responsible party's Social Security number (SSN) or individual taxpayer ID number (ITIN). You complete it in one session (it cannot be saved), and it expires after 15 minutes of inactivity.

The paper or fax Form SS-4 is for applicants who cannot use the online application, for example because the principal place of business is outside the U.S. The SS-4 instructions list fax (generally an EIN back by fax within 4 business days) and mail (complete the form at least 4 to 5 weeks before you need the EIN; the instructions say it arrives in about 4 weeks). International applicants can also apply by telephone. The instructions say to use only one method for each entity, so you do not receive more than one EIN for it.

If you are creating a corporation or LLC, the IRS says to form it through the secretary of state before you apply for an EIN, or the application may be delayed. RepeatForm helps with the paper SS-4 PDF only. It does not apply for your EIN or send anything to the IRS.

The PDF on irs.gov is marked Form SS-4 (Rev. 12-2025). The IRS About page also offers the instructions. RepeatForm does not supply the blank form: get it from irs.gov.

Line 1 is the legal name of the entity (or individual) the EIN is for, line 2 the trade name if different, line 3 an executor, administrator, trustee or care-of name, lines 4a and 4b the mailing address, and lines 5a and 5b the street address if different. Line 6 is the county and state where the principal business is located. Line 7a is the responsible party's name, and 7b their SSN, ITIN or EIN. Line 8a asks whether the application is for an LLC. Line 9a is the type of entity (check only one box) and 9b the state or country of incorporation. Lines 10 to 18 cover the reason for applying, the date the business started, the closing month of the accounting year, the highest number of employees expected, and more. The form says which lines to complete for a new business without employees and for one that has hired employees. RepeatForm does not choose your entity type or reason: read the instructions or ask your tax adviser.

Signature

The application is signed and dated by the applicant. You sign each copy yourself.