How to Get an EIN After Forming Your LLC

To get an EIN for an LLC, apply free through the IRS EIN Assistant at irs.gov/EIN; the online tool issues your nine-digit number immediately once you provide the LLC’s legal name, a U.S. street address, and a responsible party with a Social Security Number or Individual Taxpayer Identification Number. Fax applications take about five business days, and mailed applications take roughly 30 days after the IRS receives them.¹

Does Your LLC Need an EIN?

A multi-member LLC always needs an EIN because the IRS treats it as a partnership that must file its own return. A single-member LLC needs one only if it has employees or owes excise taxes; otherwise it can use the owner’s Social Security Number for federal tax purposes.²

Most single-member owners get one anyway. Banks generally require an EIN to open a business account, some states require it for tax registration, and using it on invoices and W-9 forms in place of your SSN reduces identity-theft exposure. It’s free and quick, so the practical answer for most LLCs is yes.

What to Gather Before You Apply

Collect the following before you open the application. Getting these wrong, especially the legal name, is what causes rejections and delays.

Your LLC’s legal name, spelled exactly as it appears on your filed Articles of Organization.
A physical U.S. street address where the LLC operates or receives legal documents. A P.O. Box alone won’t satisfy the street address line, though you can list one as a separate mailing address.
The responsible party: one individual who controls or manages the LLC and its funds.
That person’s SSN or ITIN. The online tool requires a valid one.³
The LLC’s formation date and the closing month of its fiscal year (December for most).
The highest number of employees you expect in the next 12 months, split into agricultural, household, and other. Zero is a valid answer.

You don’t file a paper Form SS-4 when you apply online, but reading through it first is the fastest way to make sure you have every answer ready.⁴

If No Member Has an SSN or ITIN

The online application will not work. Foreign-owned LLCs whose responsible party lacks a U.S. taxpayer ID must apply by phone or by mailing or faxing Form SS-4. On Line 7b, write “N/A” where the form asks for the responsible party’s SSN or ITIN.⁵ International applicants can call 267-941-1099 (not toll-free), Monday through Friday, 6 a.m. to 11 p.m. Eastern time, and receive the EIN during the call.⁶

The Four Ways to Apply

Online

The IRS EIN Assistant runs 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, all Eastern time.³ You pick your entity type, answer the same questions that appear on Form SS-4, review your entries, and submit. The EIN is assigned immediately and you can download the confirmation as a PDF.

One limit catches people forming multiple companies: the IRS issues only one EIN per responsible party per business day through the online tool.³ Spread applications across days, or use fax for the extras.

To use the online path at all, your LLC needs a U.S. principal business address and your responsible party needs a valid SSN or ITIN. Otherwise, use one of the methods below.

Fax

Complete Form SS-4 and send it to the fax number that matches your situation. For LLCs with a principal office in any U.S. state or the District of Columbia, fax 855-641-6935. For entities with no legal residence or principal office in any state, fax 855-215-1627 from inside the U.S. or 304-707-9471 from abroad.⁷ Processing takes about five business days.¹

Mail

Mail the completed Form SS-4. Domestic applicants send it to:

Internal Revenue Service
Attn: EIN Operation
Cincinnati, OH 45999

Applicants with no principal office in any U.S. state send it to:

Internal Revenue Service
Attn: EIN International Operation
Cincinnati, OH 45999⁸

Mail is the slowest route, roughly 30 days after the IRS receives it.¹

Phone (International Applicants Only)

If your LLC’s principal business location is outside the United States, call 267-941-1099, Monday through Friday, 6 a.m. to 11 p.m. Eastern time. The line is not toll-free. The agent walks through the SS-4 questions and issues the EIN during the call.⁶

An EIN Is Free — Watch for Impersonator Sites

The IRS charges nothing for an EIN, whether you apply online, by fax, by mail, or by phone.³ If a site is asking for payment to “file” your EIN, it isn’t the IRS.

The Federal Trade Commission has warned operators of websites that charge up to $300 for EIN filing services while mimicking IRS branding, using government-style layouts and names like “EIN Assistant” to appear official. Companies violating the FTC’s Impersonation Rule face civil penalties of up to $53,088 per violation.⁹ The real application is at irs.gov/EIN. Type that address in directly rather than clicking a search ad.

Your CP 575 Confirmation Notice

Once the IRS processes your application, it issues a CP 575 notice confirming your EIN, the LLC’s legal name and address, and the federal tax forms your business is required to file. Online applicants can download it immediately as a PDF. Fax and mail applicants receive a paper copy at the address on the application, typically within four to six weeks.

Check the notice for errors in the business name or address before you file it away. The CP 575 is the only original confirmation the IRS sends, and banks and state agencies will ask for it repeatedly. Store it with your Articles of Organization.

If You Lose the Notice

An EIN is permanently assigned to your LLC and doesn’t expire, so losing the paper doesn’t mean losing the number. Check prior tax returns, bank records, and any IRS correspondence first. If nothing turns up, call the IRS Business and Specialty Tax Line at 800-829-4933, Monday through Friday, 7 a.m. to 7 p.m. local time. After verifying your identity, the agent can give you the number and issue a 147C letter as replacement verification.⁶

When You’ll Need a New EIN Later

Most routine changes don’t require a new EIN. Changing your LLC’s name, moving to a new address, or electing S-corp or C-corp taxation all keep the same number; a name change is handled by notifying the IRS on your next return.¹⁰

You do need a new EIN if you dissolve the LLC and form a new corporation or partnership in its place, or if a single-member LLC that had been using the owner’s SSN starts having employees or excise tax obligations, in which case the LLC itself needs its own number.¹⁰ The dividing line is replacement versus restructuring: a replaced entity gets a new number, a restructured one usually keeps its old one.

1
Internal Revenue Service. Processing Status for Tax Forms
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Internal Revenue Service. Single Member Limited Liability Companies
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Internal Revenue Service. Get an Employer Identification Number
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Internal Revenue Service. Instructions for Form SS-4 (Rev. December 2025)
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Internal Revenue Service. Taxpayer Identification Numbers (TIN)
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Internal Revenue Service. Employer Identification Number
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Internal Revenue Service. Where to File Your Taxes for Form SS-4
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Internal Revenue Service. Instructions for Form SS-4 (12/2025)
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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
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Internal Revenue Service. When to Get a New EIN