How long it takes to get an EIN depends almost entirely on which application method you use, not on anything specific to your business. Apply online through the IRS and you can have your EIN before you close the browser tab. Apply by fax, mail, or phone instead, and the timeline stretches from a few business days to roughly a month.
Not every applicant qualifies for the fast option, though. Without a US Social Security Number or ITIN, or with a business whose principal location is outside the US, the online tool is off the table entirely, not just slower.
This piece covers what the IRS itself states about processing time for each of the four methods. If you haven't filed Form SS-4 yet, how to get an EIN walks through the application itself; this piece picks up from there.
Fastest option: Apply online directly through the IRS and, if approved, your EIN is issued immediately in the same session.
No SSN or ITIN? The online tool isn't available to you, even if your company is a US entity with a US address and a US-based team. You'll apply by fax or mail instead, or by phone if your business is also based outside the US, where the IRS assigns the EIN during the call.
Plan around the method, not just the form: Form SS-4 is identical no matter how you apply. What changes is the channel: online is immediate once approved, fax is about 4 business days, mail is about 4 weeks.
How long does it take to get an EIN?
It depends on how you apply. Per the IRS, an online application issues your EIN immediately once it's approved; a faxed Form SS-4 comes back in about 4 business days if you include a return fax number; and a mailed SS-4 takes approximately 4 weeks. Applicants whose business is based outside the US can also apply by phone, where the EIN is assigned during the call.
Best for founders forming a Delaware C-corp who want their company formed and a business account opened in the same flow, subject to approval: Rho. When you incorporate a Delaware C-corp with Rho, your EIN application is filed for you. We assess formation options on price, what's included, and whether a business account can open in the same flow as formation.
How long it takes to get an EIN, by application method
Method | Who can use it | Typical processing time | Notes |
|---|---|---|---|
Online (IRS EIN Assistant) | Responsible party with a valid SSN or ITIN; entity formed in the US or a US territory; principal business location in the US or a US territory | Immediate, same session | Must be completed in one sitting. The session expires after 15 minutes of inactivity and can't be saved partway through. |
Fax | Anyone, including applicants without an SSN or ITIN | About 4 business days | Only if you include a return fax number on Form SS-4. The IRS no longer provides the Form SS-4 notated with the EIN. |
Anyone | Approximately 4 weeks | The slowest of the IRS's published methods. High inventory at the IRS can push this longer. | |
Phone (international applicants only) | Businesses with no legal residence, principal place of business, or principal office in the US or a US territory | EIN assigned during the call | Available Monday through Friday, 6 a.m. to 11 p.m. Eastern time, at 267-941-1099 (not toll-free). |
Figures above reflect the IRS's published guidance on IRS.gov as of October 17, 2026.
One rule applies across every method: you can apply for only one EIN per responsible party, per day, whether you go online, by phone, by mail, or by fax. The same four methods and timelines apply whether you're applying for an LLC, a corporation, a trust, or an estate.
If you're a typical US-based applicant, start with the online section below. If you don't have an SSN or ITIN, or your company's principal location is outside the US, skip ahead to the no-SSN section instead.
Why the online option is fastest (and who it excludes)
The IRS's online EIN Assistant issues an EIN the moment your application is approved. No letter, no callback, no fax cover sheet. That speed comes with a real eligibility gate, though:
SSN or ITIN: The responsible party needs a valid SSN or ITIN.
US formation: The entity has to be formed or created in the US or a US territory.
US location: The business's principal location has to be in the US or a US territory.
Miss any one of those and the online tool isn't an option, regardless of how quickly you'd otherwise qualify. There's also a practical constraint even for eligible applicants: the application has to be completed in a single sitting. It can't be saved and resumed, and it times out after 15 minutes of inactivity. The tool is available Monday through Friday from 6 a.m. to 1 a.m. (the next day), Saturday from 6 a.m. to 9 p.m., and Sunday from 6 p.m. to midnight, Eastern time.
What slows down fax and mail applications
Fax and mail applicants submit the same Form SS-4 as everyone else. The difference is what happens after you send it.
By fax, the IRS states it will fax a cover sheet with your EIN back in about 4 business days, but only if you included a return fax number on the form. Skip that field and there's nothing for the IRS to send your EIN back to quickly.
By mail, the IRS states you'll get your EIN in approximately 4 weeks, and its instructions suggest completing Form SS-4 at least 4 to 5 weeks before you'll need the number. The IRS itself notes that high inventory levels can push processing beyond that, so a mailed application arriving during a busy season can run longer.
A couple of other things can slow either method down:
Incomplete form: An incomplete field on Form SS-4
Name mismatch: A responsible party name that doesn't match IRS records
Bad transmission: An illegible fax transmission
A rejected or bounced application means starting the clock over, so it's worth a second look at your SS-4 before you send it.
If you don't have an SSN or ITIN
The online tool has three separate requirements, and missing any one of them takes it off the table: a valid SSN or ITIN for the responsible party, US or US-territory formation for the entity, and a US or US-territory principal business location.
If you personally don't have an SSN or ITIN, online isn't available to you, even if your company is a US entity with a US address and a US-based team. Without an SSN or ITIN, you apply by fax or mail instead, using the same Form SS-4 and the same published timelines described above: about 4 business days by fax, approximately 4 weeks by mail. On line 7b of the form, the IRS instructions say to enter "Foreign" or "N/A" if the responsible party doesn't have and is ineligible to obtain an SSN or ITIN.
If your business's principal place of business is outside the US, the online tool isn't available either, regardless of whether the responsible party has an SSN or ITIN. In that case, you also have the option to apply by phone at 267-941-1099, Monday through Friday, 6 a.m. to 11 p.m. Eastern time, and the IRS representative assigns the EIN during the call.
International applicants can also fax Form SS-4 to 855-215-1627 (from within the US) or 304-707-9471 (from outside the US), or mail it to the IRS's EIN International Operation in Cincinnati, Ohio.
What to do while you wait for your EIN
Once your EIN is issued, most of what you'll want to do with it is available right away. Per the IRS, you can use it immediately to open a bank account, apply for business licenses, and file a tax return by mail.
A few things do require a short wait regardless of application method: the IRS states you should allow up to 2 weeks before your EIN will pass its TIN Matching Program, before you e-file a return, or before you make electronic tax deposits.
That gap is a good window to get the rest of your setup in order. Pull together your formation documents and have your business bank account application ready, so you're not starting from zero once the EIN lands. For how account opening can run alongside the IRS step, see opening a business bank account before your EIN arrives.
Where Rho fits
If you're forming a new company, Rho forms Delaware C-corps for $400. When you incorporate a Delaware C-corp with Rho, your EIN application is filed for you after the certificate. Your Rho business account opens in the same flow, before the EIN arrives, conditional on approval, and funds can move once the EIN is issued and attached.
To be eligible for the Delaware C-corp flow, your company needs at least one US-based owner or officer, a physical US operating address, and a business in a non-excluded industry.
Rho also forms LLCs for $349 all in, state filing fee included.
Best for: founders forming a Delaware C-corp who want their company formed and a business account opened in the same flow, subject to approval.
FAQs
The most common causes are a session timeout (the online tool expires after 15 minutes of inactivity), an entity type or ownership structure the online tool doesn't support, or having already applied for one EIN that day under the same responsible party. If the online tool isn't working for your situation, fax or mail are the fallback options.
Nothing. Getting an EIN directly from the IRS is free, regardless of application method. Any fee you encounter is for a third party preparing or filing the form on your behalf, not for the EIN itself.
The same amount of time it takes any other entity type. EIN timing runs on the four-method clock described above (immediate online, about 4 business days by fax, approximately 4 weeks by mail) regardless of whether you formed an LLC, a C-corp, or another entity type. Forming an LLC doesn't add or remove processing time on its own; you apply for the EIN once the LLC is officially formed with the state.
For an online application, approval and issuance happen in the same session, so you'll see your EIN on screen before you close the browser tab. For fax, the IRS faxes back a cover sheet with your EIN, provided you included a return fax number. For mail, you'll receive a confirmation letter. If a letter is lost, you can also confirm your EIN through a business tax transcript, your Business Tax Account if you're eligible, or by calling the IRS business line for a replacement letter.
LLC first. Form SS-4 asks for details about an already-existing entity, including its name, state of formation, and formation date, so the IRS expects your LLC (or other entity) to be formed before you apply. Apply for your EIN once your LLC is officially formed with the state, not before.
Yes, if you're eligible to apply online and your application is approved. Per the IRS, the online application issues the EIN immediately in the same session; it requires a responsible party with a valid SSN or ITIN and a business formed and based in the US or a US territory. International applicants who apply by phone get the EIN assigned during the call.
You can't use the IRS's online EIN tool without a valid SSN or ITIN. You'll apply by fax or mail instead, using the same Form SS-4: about 4 business days by fax and approximately 4 weeks by mail. If your principal place of business is outside the US, you can also apply by phone, and the IRS assigns the EIN during the call.