Key Takeaways

  • A Federal Employer Identification Number (FEIN) — also called an EIN or Federal Tax ID — uniquely identifies your LLC for federal tax purposes.
  • Most LLCs need a FEIN if they have multiple members, employees, or elect corporate tax treatment.
  • The FEIN is essential for filing business taxes, opening a business bank account, and building credit.
  • Applying for a FEIN is free and can be done quickly online via the IRS website using Form SS-4.
  • A FEIN also helps legitimize your business, supports compliance with payroll and excise tax laws, and facilitates working with vendors and lenders.

Tax ID Number for LLC

The IRS uses a tax ID number for LLC (limited liability company), also known as the LLC's employer identification number (EIN), for the determination of the LLC as a business entity for tax purposes. The IRS classifies a limited liability company as a partnership, a corporation, or a taxable disregarded entity – meaning that for tax purposes there is no separation of the business from its owner. Using the employer identification number helps to make completing paperwork for the company go smoothly and fulfills the tax obligations for the LLC.

Do All Limited Liability Companies Need to Have a Tax ID Number?

An employer identification number is required if one of the following is true:

  • An LLC currently has workers employed
  • An LLC has more than one owner
  • A sole-proprietor LLC is on the verge of hiring its first employee

What Is the Significance of Having a Tax ID Number?

For an LLC to open a business banking account, the company must have an employer identification number. The tax ID number gets used on the company's business and tax documents. Banks require a tax ID number for an LLC, so the institution can quickly identify the company.

In addition to providing the EIN, banks will also need a copy of the LLC's articles of organization. The purpose of obtaining this from the company is so the bank can prove the LLC is a legally separate entity from its members.

Another important reason for an LLC to have a tax ID number is related to business relationships. Some vendors refuse to conduct business with an LLC that does not have an employer identification number. It's beneficial for a company to have its tax ID number so the company can purchase products at wholesale price from particular sellers.

FEIN Requirements by Business Type

While all corporations must obtain a FEIN, some LLCs and sole proprietorships are only required to have one under specific conditions. You’ll need a FEIN if your business:

  • Has employees or pays payroll taxes.
  • Operates as a multi-member LLC or partnership.
  • Withholds taxes for non-resident aliens.
  • Files excise, alcohol, or tobacco tax returns.
  • Elects S-corp or C-corp taxation.

Even if your LLC isn’t legally required to have one, applying for a FEIN can make tax filing, hiring, and banking easier down the road.

What Should an LLC Know About Obtaining a Tax ID Number?

An LLC can get a tax ID number from the IRS with a choice of four methods:

  • By phone and speaking with an IRS representative
  • By visiting the IRS website
  • By fax
  • By mail

When choosing to file by fax or mail, you must submit to the IRS a Form SS-4. Be sure to provide accurate information when completing Form SS-4, such as:

  • Nature of business activities
  • Number of employees
  • LLC business name and address
  • Address and Social Security number of an authorized representative of the LLC

When filing over the phone or via website, a tax ID number is issued immediately once you provide all the necessary information to the IRS. After faxing Form SS-4, the IRS will issue the federal tax identification number in four business days. The process takes longer when choosing to apply by mail. Once the IRS receives your Form SS-4, it sends the tax ID number for the LLC within four weeks.

You have the option to choose that a third-party service process your EIN application. However, using a service will come with service fees, while it's completely free to apply directly to the IRS.

Why a FEIN Number Is Important for Your LLC

A FEIN number is more than just a tax identifier—it’s an essential part of your LLC’s financial and legal infrastructure. In addition to fulfilling federal tax requirements, the FEIN helps your business:

  • Separate personal and business finances. It ensures clear accounting and legal separation between you and the company.
  • Comply with employment and payroll laws. Employers must use their FEIN to report employment taxes and issue W-2 forms.
  • Build business credit. Many credit bureaus and financial institutions use the FEIN to track a company’s credit profile.
  • Simplify business operations. Vendors, suppliers, and clients often require a FEIN for invoicing or contract documentation.

Even single-member LLCs without employees can benefit from obtaining a FEIN, as it adds legitimacy and simplifies future hiring or tax changes

How to File for Your Tax ID Number Online Using the IRS Website

The quickest and simplest way to get an employer identification number is by using the online application. If you are going to apply using this method, know that the system is available only at specific times Monday through Friday during the day and evening. You will be providing the same information you would if applying by using the other methods. Online submission is just an electronic version of Form SS-4.

If the LLC does not have a U.S. office, you will not be allowed to use the IRS website to apply for the federal tax ID number.

To apply, do the following easy steps:

1. Go to IRS.gov and type "EIN" in the search box on the site

2. Look for a link that reads "apply online now." Read all the instructions given for obtaining an EIN.

3. Click on the "begin application" button. You will be asked to identify the structure of the company; click on the "limited liability company" button. Be sure to enter all the necessary information once prompted by the system.

Maintaining and Updating Your FEIN

Once you have a FEIN, your LLC must maintain accurate IRS records. You should update your FEIN information when:

  • The business changes its legal name or ownership structure.
  • The LLC adds or removes members.
  • The business relocates or changes mailing address.

You can update your FEIN record by writing to the IRS and including your company’s legal name, FEIN, and details of the change. Keeping this information current prevents filing errors and delays with tax processing.

Additional Ways to Apply for a FEIN Number

If you cannot apply online, you can request a FEIN using alternative IRS methods:

  1. By Fax: Complete and fax Form SS-4 to the IRS service center. You’ll usually receive your FEIN within four business days.
  2. By Mail: Mail the completed Form SS-4. Processing can take up to four weeks.
  3. By Phone (for international applicants): If your LLC’s principal office is outside the U.S., you can call the IRS at +1-267-941-1099 to apply directly.

It’s free to apply for a FEIN regardless of the method. Be cautious of third-party services that charge fees for this process—they often use the same IRS form you can file yourself.

Frequently Asked Questions

  1. What is a FEIN number used for?
    A FEIN identifies your business to the IRS for tax purposes. It’s also required to open a business bank account, hire employees, and file federal taxes.
  2. Can I use my Social Security Number instead of a FEIN?
    Single-member LLCs with no employees may use a Social Security Number, but a FEIN is recommended to protect your identity and maintain legal separation.
  3. Does a FEIN expire?
    No, your FEIN remains valid for the lifetime of your LLC. However, if the ownership structure or entity type changes, you may need a new number.
  4. How long does it take to get a FEIN?
    If you apply online, you’ll typically receive your number immediately after submission. Fax and mail applications take longer—several days to weeks.
  5. Is it safe to share my FEIN with vendors or clients?
    Yes, it’s safe when used for legitimate business or tax purposes. However, protect your FEIN like other sensitive business information to avoid misuse.

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