Getting an EIN (also called an EIN number) is one of the first pieces of paperwork every new business needs, and the good news is it's free and usually fast. The IRS gives you three ways to apply: online, by fax, or by mail, plus a phone option if your business doesn't have a US-based responsible party. Online is fastest (you can walk away with your EIN the same session), but it comes with eligibility limits that fax and mail don't have.
This guide walks through what you need before you apply, how each application method works, current IRS processing times, and what happens if the person applying doesn't have a Social Security number.
Fastest option: Apply online through the IRS EIN Assistant and you can receive your EIN immediately, but only if your business is US-based and the responsible party has a valid SSN or ITIN.
What you need first: Form your business entity with the state before you apply. The IRS wants a legally formed LLC, corporation, or partnership on file, not a plan to form one.
No SSN or ITIN? You can still get an EIN, but you'll need to apply by fax (or by phone if you're an international applicant), which takes longer than the online path.
What is an EIN and why you need one
An EIN, or Employer Identification Number, is the nine-digit number the IRS assigns to identify your business for tax purposes. It's what a bank, a state tax agency, or a payroll provider uses to recognize your business the way a Social Security number identifies an individual. You'll need one to open a business bank account, hire employees, file certain tax returns, and apply for most business credit products.
If you're trying to confirm a number you already have rather than apply for a new one, see how to look up an EIN you already have. And if the terminology needs sorting out first, here's how an EIN differs from a TIN.
What you need before you apply
The IRS won't issue an EIN to a business that doesn't legally exist yet. Before you start the application, have these ready:
Your business already formed with the state. Form your business entity first, then apply for the EIN. Applying before the entity is on file with the state risks delay or rejection.
A responsible party. This is the person who ultimately owns or controls the business and who the IRS will associate with the EIN. They need a valid SSN or ITIN to apply online; see the section below if they don't have one.
Your entity type. Sole proprietorship, single-member LLC, multi-member LLC, corporation, partnership, and so on. The SS-4 form asks you to specify this, and picking the wrong one is a common source of delay.
A mailing address and the legal business name, exactly as it's registered with the state. A mismatch here is another frequent cause of rejected applications.
Only one EIN is issued per responsible party per day, across all application methods, so plan accordingly if you're forming more than one entity.
How to apply for an EIN: the 3 ways to file Form SS-4
Every EIN application, regardless of channel, is the same underlying form: IRS Form SS-4. The channel you use just determines how fast you get an answer.
Apply online (IRS EIN Assistant)
This is the fastest method and the one most US-based businesses should use. The online assistant is available Monday through Friday, 6:00 a.m. to 1:00 a.m. Eastern time (the next day), Saturday 6:00 a.m. to 9:00 p.m., and Sunday 6:00 p.m. to midnight. If you're approved, your EIN is issued immediately and you can print your confirmation letter (the CP 575) on the spot.
Two catches: your session can't be saved partway through, and it expires after 15 minutes of inactivity, so have all your information ready before you start. You're only eligible to use this method if your principal place of business is in the US or a US territory, and if the responsible party has a valid SSN or ITIN.
Apply by fax
If you're not eligible for the online tool, or you'd rather not deal with the session time limit, you can fax a completed SS-4 to the IRS. Domestic applicants fax to 855-641-6935. This is also the route for a responsible party without an SSN or ITIN, and for applicants whose principal place of business is outside the US, who fax instead to 855-215-1627 (from within the US) or 304-707-9471 (from outside the US).
Apply by mail
Mail is the slowest option, and mostly makes sense if fax isn't practical for you. Send the completed SS-4 to Internal Revenue Service, Attn: EIN Operation, Cincinnati, OH 45999. International applicants without a US address use the same city with "Attn: EIN International Operation" instead.
Apply by phone (international applicants only)
If your business has no US legal residence or principal place of business, you can apply by calling 267-941-1099, Monday through Friday, 6:00 a.m. to 11:00 p.m. Eastern time. This isn't a general workaround for domestic applicants without an SSN. It's specifically for businesses without a US presence at all.
Processing times by method
Method | Who can use it | Typical processing time | Notes |
|---|---|---|---|
Online | US-based responsible party with a valid SSN or ITIN | Immediate | Fastest option; session expires after 15 minutes idle |
Fax | Anyone, including responsible parties without an SSN or ITIN | About 4 business days | Domestic fax: 855-641-6935. The EIN itself typically comes back by fax in about 4 business days either way; non-SSN/ITIN applicants should still plan on roughly 2-3 extra weeks before the full process (confirmation letter included) wraps up. |
Anyone | About 4 weeks | Slowest option; IRS notes high volume can add further delay | |
Phone | International applicants (no US presence) only | Varies by call | 267-941-1099, M-F 6 a.m.-11 p.m. ET |
These are current IRS-published figures, not guarantees. Mail volume in particular can push processing past the stated timeframe.
If you don't have an SSN or ITIN
A responsible party without a US Social Security number or ITIN can still get an EIN, just not through the online assistant. On the SS-4 itself, enter "Foreign" or "N/A" in the field asking for the responsible party's SSN or ITIN, then apply by fax (or by phone if your business has no US presence at all, as described above).
Expect this to add roughly two to three extra weeks to the timeline compared with the online path. That's the tradeoff for not having an SSN on file: the application itself works fine, it just moves through a slower channel. This doesn't change your eligibility to form or run a US business; it only affects how long the EIN itself takes to arrive.
Common mistakes that delay an EIN application
A few errors account for most of the rejected or delayed SS-4 filings the IRS sees:
Applying before the entity is formed. The state filing needs to be done first.
Choosing the wrong entity type on the form. Single-member LLC and multi-member LLC, for instance, are treated differently.
A business name or address that doesn't match your state filing exactly. Even small discrepancies can trigger a manual review.
Trying to use the online assistant outside its posted hours, or letting the session time out mid-application.
Double-checking these before you submit will save you a resubmission and, if you're on the fax or mail track, another multi-week wait.
What to do once you have your EIN
Once your EIN is issued, most of what comes next moves quickly: you can open a business bank account, apply for a business credit card, and register for state and payroll taxes. A few sibling pieces cover those next steps in more depth, including how to open a business bank account before your EIN arrives and how to get a business credit card with just an EIN.
If you incorporate through Rho, your SS-4 (EIN application) is prepared and submitted for you as part of that same flow, and account opening runs in parallel with EIN issuance rather than waiting on it. Funds still can't move until the EIN itself is issued and attached to the account, since that's an IRS timeline, not a banking one.
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FAQs
Yes. The IRS issues EINs at no cost directly to applicants. Some formation services charge a separate fee, commonly in the $79-$99 range, to file the SS-4 on your behalf, but there's no requirement to pay anyone to do this yourself.
No, not in the sense of having a finished application accepted. The IRS expects your entity to already be legally formed with the state before you apply. Applying earlier risks delay or rejection.
Yes. Applying for an EIN doesn't require a lawyer, an accountant, or a paid formation service. Anyone can complete Form SS-4 directly with the IRS, whether through the online assistant, by fax, by mail, or by phone for international applicants. The one step you can't skip is having your entity legally formed with the state first.
Sometimes, for federal tax filing purposes, if the LLC has no employees. In practice, most banks require an EIN to open a business account regardless, so most single-member LLC owners get one anyway.
They can still apply, just not through the online assistant. Enter "Foreign" or "N/A" on the SSN/ITIN field and apply by fax, or by phone if the business has no US presence. Expect roughly two to three extra weeks compared with the online path: the EIN itself typically comes back by fax in about 4 business days either way, but non-SSN/ITIN applicants should still plan on that 2-3 week window before the full process (confirmation letter included) wraps up.
Yes, if you're eligible. US-based applicants with a valid SSN or ITIN who apply through the IRS EIN Assistant during its posted hours receive their EIN immediately upon approval.