An Employer Identification Number is a federal tax ID for an entity — a company, a trust, an estate. You need one to open a US business bank account, to file a Form 5472, to hire employees, and for most payment processors.

It is free. The IRS is blunt about this: "Beware of websites that charge for an EIN. You never have to pay a fee for an EIN."

The four ways to apply

Method	Who can use it	Turnaround
Online at IRS.gov/EIN	US and US-territory applicants only. The responsible party must have a valid SSN, ITIN or EIN, and the business must have a US principal place of business	Immediate
Phone: 267-941-1099	International applicants only. Not toll-free. Mon–Fri, 6:00 a.m. to 11:00 p.m. Eastern	Same call
Fax	Domestic 855-641-6935. International 855-215-1627 from inside the US, or 304-707-9471 from outside. 24 hours	Generally within 4 business days
Mail	Domestic: IRS, Attn: EIN Operation, Cincinnati OH 45999. International: IRS, Attn: EIN International Operation, Cincinnati OH 45999	About 4 weeks

Online tool hours, Eastern time: Monday to Friday 6:00 a.m. to 1:00 a.m.; Saturday 6:00 a.m. to 9:00 p.m.; Sunday 6:00 p.m. to midnight.

The point most people get wrong

You do not need an SSN or ITIN to get an EIN.

The SSN/ITIN requirement applies only to the online system. If you are an international applicant, you apply by phone or by fax, and on line 7b of Form SS-4 you enter "Foreign" where a US tax ID would go.

This matters because a great deal of online commentary tells non-residents they must first obtain an ITIN — a process taking seven weeks or more — before they can get an EIN. That is not what the IRS instructions say.

The responsible party

Every EIN application names a responsible party. The rules:

• It must be an individual — a natural person, not a company. The only exception is for government entities.
• That person must have a valid SSN, ITIN or EIN, or be a foreign person entering "Foreign" on the paper form.
• The responsible party is the person who controls, manages or directs the entity and the disposition of its funds.

Limit: one EIN per responsible party per day. If you are forming several entities, you cannot do them all in one afternoon.

Applying by phone, step by step

This is the fastest route for a non-US applicant.

1. Complete Form SS-4 before you call. The IRS representative will read it to you line by line. Having it filled in makes the call short.
2. Call 267-941-1099, Monday to Friday, 6:00 a.m. to 11:00 p.m. Eastern. Convert that to your own time zone before dialling — the number is only staffed in those hours.
3. Be ready to confirm you are authorised to receive the EIN on behalf of the entity.
4. Write the number down when they give it to you. You get it on the call. Confirmation by post follows later.

Applying by fax

If you cannot make the call hours work, fax Form SS-4 to 304-707-9471 from outside the US. Include a return fax number and you should have the EIN within about four business days.

Keep the fax transmission report. It is your evidence of the filing date.

What it costs

Nothing. The IRS charges no fee by any of the four methods.

Third-party services do charge — often $100 to $300 — for filling in a form you can complete yourself in twenty minutes. Some of them are legitimate agents; the fee buys convenience, not access. None of them can get you an EIN faster than the phone route, which is same-day.