Form SS-4 & EIN Application

How to Submit Form SS-4: Online Phone Fax and Mail Methods Compared

5 min readQ&A Guide

Written byLipai WangFounder · IRS-registered tax professional

Filing path

EIN application flow (Form SS-4)

How a foreign-owned entity obtains its IRS Employer Identification Number.

Gather entity details
Legal name, responsible party, and structure.
Complete Form SS-4
Foreign responsible parties can generally apply without a U.S. TIN when the IRS foreign-applicant process applies.
Submit to the IRS
Fax or mail — international applicants can also call.
Receive the EIN
Use it to open banking and file federal returns.

Key formsForm SS-4EIN

Key Takeaways

Online: Fastest (immediate EIN), but only for U.S./territory applicants with SSN or ITIN
Phone: Call 267-941-1099 for international applicants (not toll-free), EIN issued during the call
Fax: Approximately 4 business days processing via the Fax-TIN program
Mail: Slowest at approximately 4 weeks — mail 4-5 weeks before you need the EIN
Only use one submission method per entity to avoid duplicate EINs
The IRS does not charge any fee for EIN applications — beware of fee-charging websites
If EIN is needed before it arrives, write "Applied For" on returns that require it

What is the fastest way to get an EIN?

The fastest method is the IRS online EIN application, which provides an EIN immediately upon completion. The application is available at irs.gov, is free, and takes about 10-15 minutes to complete.

However, the online application is only available to applicants with a principal business located in the United States or U.S. territories, and the responsible party must have an SSN or ITIN. If you do not meet these requirements, the phone method is the next fastest option.

How does the phone application work for international applicants?

International applicants can call the IRS at 267-941-1099 (not a toll-free number). The line is available Monday through Friday, 6:00 a.m. to 11:00 p.m. Eastern Time. Have your completed Form SS-4 in front of you before calling, because the IRS agent will walk through each line.

The agent will issue your EIN over the phone during the call. You should receive your formal confirmation letter (CP 575) by mail within a few weeks. Write down the EIN the agent gives you, as you can use it immediately.

Can you apply by fax?

Yes. The Fax-TIN program lets you fax your completed Form SS-4 to the IRS. Processing typically takes about 4 business days. The IRS will fax the EIN back to the number you provide on the form.

There are different fax numbers for domestic and international applicants. Check the current IRS instructions for Form SS-4 to get the correct fax number for your situation. Make sure the fax number you provide for the response is working and can receive faxes.

What about applying by mail?

Mail is the slowest method. Processing takes approximately 4 weeks. Mail your completed Form SS-4 to the IRS address listed in the instructions (the address varies based on whether you are a domestic or international applicant).

Because of the long processing time, plan to mail your application 4-5 weeks before you need the EIN. This method is generally a last resort for most applicants.

Are there any important warnings about the application process?

Only use one method per entity. Do not submit Form SS-4 online and then also fax or mail it. Using multiple methods for the same entity can result in duplicate EINs, which creates complications that require IRS intervention to resolve.

Also beware of third-party websites that charge fees to file Form SS-4. The IRS does not charge anything for EIN applications. If a website is asking for payment to get you an EIN, you are not on the official IRS site. The official online application is at irs.gov and is completely free.

Frequently Asked Questions

What happens if I accidentally submit Form SS-4 twice?

You may receive duplicate EINs, which creates problems. Contact the IRS at 267-941-1099 to resolve it. They can cancel the duplicate and keep the original. Only use one submission method per entity.

Is the IRS online EIN application really free?

Yes. The official IRS online application at irs.gov is completely free. Any website charging a fee is a third-party service, not the IRS. You do not need to pay anyone to get an EIN.

Can I use my EIN right away after getting it by phone?

Yes. The EIN is valid immediately. You can use it to open bank accounts, file returns, and conduct business. Your formal confirmation letter (CP 575) will arrive by mail within a few weeks.

What number do I call to apply for an EIN from outside the U.S.?

Call 267-941-1099. This is not a toll-free number. Hours are Monday through Friday, 6:00 a.m. to 11:00 p.m. Eastern Time. Have your completed Form SS-4 ready before calling.

form ss-4EINemployer identification numbertax IDEIN application

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