How to Get a Federal Employer Identification Number

To get a federal Employer Identification Number, apply directly with the IRS — it’s free, and the online application at irs.gov issues the number immediately in most cases. An EIN is the nine-digit tax ID the IRS assigns to businesses, nonprofits, estates, and trusts, and it functions for your entity the way a Social Security number does for a person. Fax, mail, and phone applications are also available if the online tool isn’t an option for you.

Do You Actually Need an EIN

Not every business does. A sole proprietor with no employees and no federal excise tax obligation can keep using a Social Security number for tax filings. You need an EIN once any of these apply:

You hire employees and have to report employment taxes.
You operate as a corporation or a partnership, whether or not you have employees.
You owe federal excise taxes.
You administer a trust, an estate, or a retirement plan.
You change your business structure or ownership in a way that triggers a new number (more on that below).

Plenty of sole proprietors who don’t strictly need one apply anyway, so they don’t have to hand out a Social Security number on invoices and W-9 forms. That’s a valid reason on its own.

What to Have Ready Before You Apply

The IRS gathers the same information whether you use the online tool or paper Form SS-4. Have this in front of you before you start:

The entity’s legal name exactly as it appears on your formation documents, plus any trade name you use.
The entity type: sole proprietorship, partnership, corporation, LLC, trust, estate, nonprofit, or other. For an LLC, know your tax classification — a single-member LLC is a disregarded entity by default and a multi-member LLC defaults to partnership treatment.
The responsible party’s name and Social Security number or ITIN. This must be an individual who actually owns, controls, or directs the entity and its funds, not a nominee. The only exception to the “must be a person” rule is government entities. For a corporation, this is typically the principal officer; for a partnership, a general partner; for an estate, the executor or administrator.¹
Your reason for applying: starting a new business, hiring employees, banking, creating a trust, and so on.

One quiet rule that trips people up: the IRS limits each responsible party to one EIN per day. If you’re standing up several entities at once, you’ll need to space the applications across business days.²

The Four Ways to Apply

Online

The IRS online EIN application is the fastest route and is available to entities whose principal place of business is in the United States or a U.S. territory. The tool walks through the same questions as Form SS-4, and if the application is approved the IRS issues the EIN on the spot with a downloadable confirmation.²

The system runs Monday through Friday from 6:00 a.m. to 1:00 a.m. the next day, Saturday from 6:00 a.m. to 9:00 p.m., and Sunday from 6:00 p.m. to midnight, all Eastern Time. You have to finish in one sitting — the tool doesn’t save progress and times out after 15 minutes of inactivity. Gather everything first.

Fax

Download Form SS-4, fill it out, and fax it to 855-641-6935. If you include a return fax number, the IRS will fax the EIN back to you in about four to five business days. Keep the transmission confirmation as proof of delivery.³

Mail

Send the completed Form SS-4 to:

Internal Revenue Service
Attn: EIN Operation
Cincinnati, OH 45999

Processing takes about four weeks, and the IRS recommends mailing at least four to five weeks before you actually need the number. Given the wait and the free faster options, mail is really only worth it if fax and online aren’t available to you.

Phone (International Applicants Only)

If your principal place of business is outside the United States, you can’t use the online tool. Call the IRS at 267-941-1099, Monday through Friday from 6:00 a.m. to 11:00 p.m. Eastern Time. A representative takes your information over the phone and issues the number during the call once your information is verified. International applicants can also fax Form SS-4 to 304-707-9471 or mail it to the Cincinnati address above marked “Attn: EIN International Operation.”³

How Long It Takes

Online: immediate, in minutes.
Fax: about four to five business days.
Mail: roughly four weeks.
Phone (international): during the call, once identity and information are verified.

What You Get, and How to Keep Track of It

However you apply, the IRS mails an official CP 575 notice to your business address confirming the EIN. Banks routinely ask to see this document when you open a business account, so file it somewhere you’ll actually find it later.

If you lose the number down the road, check the CP 575 first, then any prior business tax returns, the bank that opened your business account, or the state licensing agencies where you filed for permits. As a last resort, call the IRS Business and Specialty Tax Line at 800-829-4933, Monday through Friday from 7:00 a.m. to 7:00 p.m. local time. The agency will verify your identity before releasing the number.³

When a Change Means You Need a New EIN

Changing your business name or moving to a new address does not require a new EIN. Changing your entity’s structure or ownership often does. The rules vary by entity type:

A sole proprietor needs a new EIN when incorporating, forming a partnership, or declaring bankruptcy.
A corporation needs a new EIN when it receives a new charter from the secretary of state, becomes a subsidiary, converts to a partnership or sole proprietorship, or merges to form a new corporation.
A partnership needs a new EIN when it incorporates, when one partner takes over the business as a sole proprietor, or when the partnership dissolves and a new one begins.
An LLC needs a new EIN when it terminates and forms a new corporation or partnership, or when a single-member LLC becomes required to file employment or excise taxes.
An estate needs a new EIN when it creates a trust with estate funds, or when a sole proprietorship continues after the owner’s death.
A trust needs a new EIN when converting from revocable to irrevocable, when it becomes an estate, or when property is distributed to a residual trust.

If you’re not sure whether your situation calls for a new number, the same Business and Specialty Tax Line, 800-829-4933, can tell you.⁴

The IRS Does Not Charge for an EIN

The application is free — online, by fax, by mail, or by phone. Any site asking for a fee is a third-party service, not the IRS.

The Federal Trade Commission has warned about websites that charge as much as $300 for what the government gives out for nothing. These sites imitate the IRS with government-style seals and colors, put “IRS” in their domain names, and label their tool “EIN Assistant,” which is also the name of the real IRS application. Many bury or omit any disclosure that they aren’t affiliated with the government. The genuine application is on irs.gov; if the URL doesn’t end in .gov, it isn’t the IRS.⁵

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Internal Revenue Service. Responsible Parties and Nominees
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Internal Revenue Service. Get an Employer Identification Number
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Internal Revenue Service. Employer Identification Number
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Internal Revenue Service. When to Get a New EIN
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Federal Trade Commission. FTC Warns Operators of Websites that Charge for an Employer Identification Number and Claim Affiliation with the IRS