Formation 2026-02-17

What Is an EIN?

An Employer Identification Number (EIN) is a unique nine-digit number assigned by the Internal Revenue Service (IRS) to identify your business for tax purposes. Think of it as a Social Security number for your LLC. It is also sometimes called a Federal Tax Identification Number or Federal Employer Identification Number (FEIN).

The format of an EIN is XX-XXXXXXX, and once assigned, it stays with your LLC for its entire existence. You will use your EIN on tax returns, bank account applications, business licenses, and any other situation where your business needs to be formally identified.

Who Needs an EIN?

While not every business structure requires an EIN, virtually every Wisconsin LLC should get one. You are legally required to have an EIN if your LLC has more than one member, hires employees, or files certain types of tax returns (such as employment, excise, or alcohol/tobacco/firearms taxes).

Even if you are a single-member LLC with no employees, you should still get an EIN because most banks require one to open a business bank account, it prevents you from having to give your personal Social Security number to clients and vendors who need your tax ID for 1099 reporting, and it provides an additional layer of identity protection.

Information You Need Before Applying

Before you apply for an EIN, gather the following information:

• Legal Name: Your LLC's full legal name exactly as it appears on your Articles of Organization filed with the Wisconsin DFI.
• Responsible Party: The name and Social Security number of the person who controls or manages the LLC. For a single-member LLC, this is typically the sole member. For multi-member LLCs, this is usually the managing member.
• Business Address: Your LLC's mailing address. This can be your principal office address or a separate mailing address.
• Formation Date: The date your LLC was formed (the date your Articles of Organization were approved by the DFI).
• Business Activity: A brief description of your LLC's primary business activity.
• Number of Employees: How many employees you expect to hire in the next 12 months (enter zero if none).

How to Apply Online (Free)

The fastest and easiest way to get an EIN is through the IRS online application at irs.gov. The process is completely free and takes about 10 to 15 minutes. Here is the step-by-step process:

Step 1: Go to the IRS EIN Assistant on irs.gov. The tool is available Monday through Friday, 7 a.m. to 10 p.m. Eastern Time.

Step 2: Select "Limited Liability Company" as your entity type.

Step 3: Select the number of members in your LLC.

Step 4: Choose why you are applying. For a newly formed LLC, select "Started a new business."

Step 5: Enter your LLC's legal name, trade name (if applicable), and business address.

Step 6: Enter the responsible party's name and SSN or ITIN.

Step 7: Provide details about your business activity, closing month of your accounting year, and expected number of employees.

Step 8: Review your application and submit. Your EIN will be issued immediately on screen.

Step 9: Download or print the EIN confirmation notice (CP 575). Keep this document in a safe place as you will need it for your bank account application and other purposes.

Alternative Application Methods

If you prefer not to apply online, you can also apply by fax (Form SS-4 faxed to the appropriate IRS office, with EIN assigned within 4 business days), by mail (Form SS-4 mailed to the IRS, with EIN assigned within 4 to 5 weeks), or by phone (only available for international applicants without a US address). The online method is strongly recommended because it is instant, free, and provides immediate confirmation.

What to Do After Getting Your EIN

Once you have your EIN, there are several important next steps. Open your business bank account using your EIN, Articles of Organization, and operating agreement. Apply for any required state or local business licenses. Set up your accounting system and make sure your EIN is on file with your accountant or tax preparer. If you plan to hire employees, register with the Wisconsin Department of Revenue for state withholding taxes and the Department of Workforce Development for unemployment insurance.

Common Questions About EINs

Can I get an EIN before my LLC is formed? No. You need to have your Articles of Organization approved by the DFI before applying for an EIN, because the IRS requires your LLC's legal name and formation state.

Does an EIN expire? No. Once assigned, your EIN is permanent and does not need to be renewed.

What if I lose my EIN? You can call the IRS Business and Specialty Tax Line at 1-800-829-4933 to retrieve it. You can also find it on previous tax returns or the original CP 575 notice.

Can I have more than one EIN? Each LLC should have only one EIN. If you have multiple LLCs, each one needs its own separate EIN.

Legal Disclaimer The information in this article is provided for general educational purposes only and does not constitute legal, tax, or financial advice. Wi Filings is not a law firm and is not authorized to provide legal advice. Every business situation is unique — consult a licensed Wisconsin attorney or qualified accountant before making decisions about your LLC's structure, compliance obligations, or financial strategy. Nothing in this article creates an attorney-client relationship between you and Wi Filings.