How to Apply for an EIN | Simple Step-by-Step Guide

Starting a business, hiring employees, or setting up a trust comes with a long list of administrative steps, and getting an Employer Identification Number (EIN) is usually near the top. The good news: the process is straightforward, it’s free, and for most applicants, it can be done in minutes online.

This guide walks you through everything you need to know, from what an EIN actually is to how to apply for an EIN, troubleshoot common issues, and put your new number to use.

What Is an EIN?

An Employer Identification Number (EIN), sometimes called a Federal Tax Identification Number, is a unique nine-digit number assigned by the Internal Revenue Service (IRS) to identify a business entity in the United States. It works much like a Social Security Number does for an individual, but it belongs to your business.

The IRS uses your EIN to track federal tax filings and payments associated with your business. Beyond that, banks, vendors, contractors, and state agencies all commonly ask for it. You’ll need it to open a business bank account, apply for licenses and permits, file tax returns, and more.

The format always looks like this: XX-XXXXXXX. Once assigned, your EIN is permanent, and it stays with that business entity for life, even if the business changes its name or address.

Who Needs an EIN?

Not every business is required to have an EIN, but most entities benefit from having one regardless of legal obligation. The IRS requires you to get an EIN (Employer Identification Number) if any of the following apply:

You have employees or plan to hire employees
Your business operates as a partnership, corporation, or multi-member LLC
You withhold taxes on income other than wages paid to a non-resident alien
You have a Keogh plan
You’re involved with certain types of organizations like trusts, estates, real estate mortgage investment conduits, non-profit organizations, farmers’ cooperatives, or plan administrators
You file tax returns for Employment, Excise, or Alcohol, Tobacco, and Firearms

Sole proprietors without employees are the one major exception since they can technically use their Social Security Number for tax purposes. However, many sole proprietors choose to get an EIN anyway to keep business and personal finances separate, reduce the risk of identity theft, and appear more established to clients and vendors.

If you’re looking to get an EIN for your LLC, know that single-member LLCs don’t automatically require one unless they hire employees or elect to be taxed as a corporation, but again, getting one is almost always advisable.

When to Get an EIN

Timing matters. You should apply for an EIN before you start hiring employees, open a business bank account, or file your first federal tax return. For many businesses, this means getting an EIN at the time of formation.

Here are the most common trigger events that signal it’s time to get an Employer Identification Number:

You’ve just registered a new LLC, corporation, or partnership
You’re about to hire your first employee
You’re opening a business bank account (most banks require an EIN)
You need to apply for a business license or permit
Your business structure has changed. For example, a sole proprietorship converting to an LLC
You’ve taken over an existing business or inherited an estate
Your organization has become a tax-exempt organization
A trust has been created that needs its own tax identification

Don’t wait until tax season to sort this out. Getting your EIN early saves you from delays down the road and keeps your business running without interruption.

Preparing to Apply for an EIN

Before you begin the EIN application, take a few minutes to gather the information you’ll need. Having everything on hand makes the process faster and helps you avoid errors that could delay your application.

Here’s what you’ll need:

Legal name of the business or entity exactly as it’s registered
Trade name or DBA (“doing business as”) if applicable
Mailing address of the principal place of business
Type of entity (LLC, corporation, sole proprietorship, partnership, trust, estate, etc.)
State and date of formation
Reason for applying (new business, hired employees, banking purposes, etc.)
Date the business started or was acquired
Closing month of the accounting year
Highest number of employees expected in the next 12 months
Principal activity or product of the business

Most importantly, you’ll need information about the Responsible Party. This is the individual who owns or controls the entity, the person who has authority over the funds, assets, or execution of the business. For a sole proprietorship, this is typically the owner. For a corporation or LLC, it may be a principal officer, general partner, or managing member.

The Responsible Party must have a valid U.S. taxpayer identification number, either a Social Security Number (SSN), an Individual Taxpayer Identification Number (ITIN), or an existing EIN. The IRS made this a requirement to improve tax compliance and reduce fraudulent applications.

Important: The IRS limits online EIN applications to one per Responsible Party per day. If you need multiple EINs for different entities, plan your applications accordingly.

How to Apply Online for an EIN

Applying online is by far the fastest and most convenient method. The IRS website offers a free EIN application through its online assistant, and eligible applicants receive their EIN immediately upon completion. There’s no waiting, no mailing, and no phone hold times.

The online EIN application is available to businesses and entities whose principal business, office, or legal residence is located in the United States or its territories. If that describes you, here’s how the process works:

Step 1: Go to the IRS website

Navigate to the EIN online application on the IRS website (irs.gov). Look for the “Apply for an EIN Online” link. Be cautious, there are third-party websites that charge fees for this service. The IRS application is always free.

Step 2: Select your entity type

You’ll be asked to identify the type of entity applying for the EIN. Options include sole proprietor, partnership, corporation, LLC, estate, trust, and others. Choose the one that accurately reflects your business structure.

Step 3: Answer the application questions

The online assistant walks you through a series of questions about your business, its purpose, location, and ownership. This is where your prepared information comes in handy. The entire EIN application typically takes about 15 minutes to complete.

Step 4: Receive your EIN

Once you submit your completed application, your EIN is issued immediately. You’ll see it on your confirmation screen. Print or save this page, it’s the official confirmation of your EIN, and you’ll want it for your records.

Session timeout: The online EIN application must be completed in a single session.
You have 15 minutes of inactivity before the system times out and you’ll need to start over.
Complete the application in one sitting to avoid losing your progress.

Note: The online EIN application is available Monday through Friday, 7 a.m. to 10 p.m. Eastern Time. It is not available on weekends or federal holidays.

How to Apply for an EIN by Phone, Fax, or Mail

If you’re unable to use the online application or simply prefer an alternative, the IRS offers three other ways to apply for an EIN. Each comes with its own timeline and process.

1. By Phone

U.S. residents with a principal business inside the United States can call the IRS Business & Specialty Tax Line to apply over the phone. A representative will ask you the same questions as the online EIN application and issue your EIN at the end of the call. This can be a good option if you prefer to speak with someone directly or have questions during the process.

Phone applications are available Monday through Friday, 7 a.m. to 7 p.m. local time. Have all your business information and Responsible Party details ready before calling, since the representative needs to complete the application in one call.

2. By Fax

You can apply by faxing a completed Form SS-4 (the official EIN application form) to the appropriate IRS fax number for your state. If you provide a return fax number on the form, the IRS will fax your EIN back to you within four business days. If not, it may take longer.

Download Form SS-4 from the IRS website, fill it out completely, and fax it to the number listed in the form’s instructions for your state.

3. By Mail

Mailing Form SS-4 is the slowest option. The IRS generally processes mailed EIN applications within four to five weeks. Only choose this method if you have significant lead time before you need your EIN for filing taxes, opening accounts, or hiring employees.

Mail your completed Form SS-4 to the address listed in the instructions based on your business location. Make sure your mailing address is clearly written, as the IRS will mail your EIN confirmation to that address.

EIN Applications for International Applicants

If your business does not have a legal residence, principal office, or principal place of business in the United States, you’re considered an international EIN applicant. This applies to foreign businesses, foreign nationals setting up a U.S. entity, and others with international ties.

International applicants cannot use the IRS online EIN application. Instead, you have two options:

Call the IRS at +1-267-941-1099 (not a toll-free number). This line is available Monday through Friday, 6 a.m. to 11 p.m. Eastern Time.
Fax or mail a completed Form SS-4 to the IRS using the instructions specific to international applicants

Processing times for international fax or mail applications are similar to domestic ones, four business days by fax, four to five weeks by mail.

Common EIN Issues and How to Fix Them

Lost or Forgotten EIN

It happens more often than you’d think. If you’ve misplaced your EIN, there are several ways to track it down before contacting the IRS:

Check your original EIN confirmation letter from the IRS
Look at a previously filed federal tax return; your EIN appears at the top
Check with your bank, if you opened a business account, they have it on file
Review old business licenses, permits, or state filings
Check with your accountant or tax preparer

If none of those options work, call the IRS Business & Specialty Tax Line. Once they verify your identity, they can provide your EIN over the phone.

Multiple EINs or Entities

Each separate legal entity needs its own EIN. A sole proprietor who incorporates their business, for example, needs a new EIN for the corporation; the one tied to them as an individual doesn’t transfer. Similarly, if you operate multiple distinct businesses under different legal structures, each one needs its own EIN.

If you’ve accidentally applied for and received multiple EINs for the same entity, contact the IRS to have the duplicate numbers cancelled. Using the wrong EIN on federal tax returns can cause significant problems with the Internal Revenue Service.

An EIN You Didn’t Request

If you receive an EIN confirmation for a business you didn’t apply for, treat it as a potential identity theft issue. Someone may have used your Social Security Number or personal information to obtain an EIN in your name.

Contact the IRS immediately at the Business & Specialty Tax Line. Report the issue, ask for the EIN to be deactivated, and consider placing a fraud alert with the major credit bureaus. Keep a record of all communications with the IRS during this process.

Ready to Apply?

Getting an EIN for your business is one of the simplest steps in setting up a business, and one of the most important. Whether you apply online in 15 minutes or mail in your Form SS-4, once you have your EIN, you’re set up to hire employees, open accounts, file your tax returns, and operate as a legitimate business entity. Head to the IRS website to apply online and get your number today.

If you prefer expert guidance to ensure your EIN is filed correctly, Foundery USA handles the entire process of EIN registration seamlessly for founders worldwide.

Frequently Asked Questions (FAQs)

1. How do I file my EIN?

The fastest way is through the IRS website using the free online EIN application, where you receive your EIN instantly. If you prefer, you can also apply by phone through the IRS Business & Specialty Tax Line, by faxing Form SS-4 to receive your EIN within four business days, or by mailing Form SS-4 if you have four to five weeks of lead time.

2. How long does it take to get an EIN?

It depends on how you apply. The online EIN application is the fastest method and you receive your EIN the moment you submit. By fax, expect your EIN back within four business days. By mail, the IRS typically takes four to five weeks to process your EIN application and return your number.

3. Is there a fee to apply for an EIN?

No. Applying for an EIN directly through the IRS is completely free, regardless of which method you use: online, phone, fax, or mail. If a website is charging you to apply for an EIN, it is a third-party service, not the IRS. Always apply online at irs.gov to avoid unnecessary fees.

4. Can I apply for an EIN before my business is officially registered?

Yes, in most cases. The IRS may issue an EIN for your business before your business is fully registered. However, it is generally best practice to have your legal business structure finalized first, especially for limited liability companies and corporations, so the EIN is tied to the correct entity type from the start.

5. Can I use my EIN immediately after receiving it?

For most purposes, yes. Once you receive your EIN you can use it to open a bank account, set up payroll, or share it with vendors right away. However, if you need it for federal tax filing purposes, the IRS system may take up to two weeks to fully register your new EIN in its database.

6. What happens to my EIN if I close my business?

Your EIN does not disappear. EINs are never reissued or reassigned to another business. If you close your business, you can request the IRS to close your business account associated with that EIN, but the number itself remains permanently on record. If you reopen or start a new entity later, you will need a new EIN for that business.

7. Do I need a new EIN if I change my business name or address?

No. A name or address change does not require a new EIN. You simply notify the IRS of the change in writing or update it when filing your tax returns. A new EIN is only required when the underlying business structure changes, for example, a sole proprietorship incorporating as an LLC or corporation.