Key Takeaways:

  • An LLC’s Tax ID Number (EIN) is required for hiring employees, opening business bank accounts, and filing taxes.
  • To locate an existing EIN, check IRS confirmation letters, past tax returns, business bank statements, or online IRS tools.
  • You can also retrieve your EIN by calling the IRS Business & Specialty Tax Line or checking with your bank, accountant, or payroll provider.
  • Applying online through the IRS website is the fastest way to get a new EIN, but you can also apply by fax or mail.
  • Protect your EIN as you would a Social Security Number to prevent identity theft.

Your LLC tax ID number is a way for the IRS to identify your company to guarantee that you are correctly reporting your company's losses and profits. 

Tax ID Introduction

All limited liability companies (LLC) with employees are required by law to obtain a tax identification number from the IRS. Multi-member LLCs are also required to have a tax number. Employer Identification Number (EIN) is another name for a tax ID number. Just as Social Security numbers are used to identify people, tax ID numbers are used to identify LLCs.

The IRS provides tax ID numbers to a wide range of business entities:

  • Corporations
  • Limited liability companies
  • Partnerships
  • Sole proprietorships

Tax ID numbers are specific to the company to which they are issued, and every number will have nine digits. When an LLC hires its first employee, or when a sole proprietorship makes the transition to an LLC, a federal tax ID number required. The owner of an LLC sole proprietorship can use his Social Security Number for tax filings as long as his business has no employees. If you are worried that including your Social Security Number on client and vendor forms will expose you to identity theft, having a tax ID number can help protect you from this issue.

You can either authorize someone in your company to apply for a tax ID number or you can handle this task yourself. If you want the flexible structure and liability protections of an LLC, there are several important tasks that you need to complete, including obtaining a federal tax identification number. The best way to make sure you don't miss any steps necessary for forming your LLC is working with an experienced attorney. 

How to Find Tax ID Number for LLC

If you already have an LLC but don’t know your Tax ID Number (EIN), there are several ways to locate it:

  1. IRS Confirmation Letter (CP 575 or 147C): The IRS sends this letter when your EIN is issued. If lost, you can request a copy by calling the IRS Business & Specialty Tax Line at 800-829-4933.
  2. Past Tax Filings: Your EIN will appear on federal tax returns, including Form 1065, 1120, or employment tax forms.
  3. Business Bank Records: Most banks require your EIN to open an account. Review your business bank statements or account paperwork.
  4. State or Local Filings: Check your state business registration portal, licenses, or permits, which often list your EIN.
  5. Third Parties: Your accountant, bookkeeper, or payroll provider will likely have your EIN on file.

For security, never share your EIN publicly and store it in a secure location. If you suspect fraud, contact the IRS immediately to safeguard your business identity.

Tax IDs and Banking

Your LLC will need a tax ID number to complete a variety of important banking tasks, such as:

Without a tax ID number, banks would have no way to identify your company. Before working with your LLC, banks will need both your tax ID number and a copy of your business's Articles of Organization. Having these items will prove that LLC members and the LLC itself are legally separate. Without a tax ID number, you won't be able to hire employees or open a business bank account, both of which are an important part of successfully operating an LLC. 

Vendors and Tax IDs

Many vendors will not work with limited liability companies that do not have a tax ID number. If your LLC has goods that it wishes you sell to the public, you will be required obtain a tax ID number. With a tax ID number, some vendors will allow you to purchase items wholesale. If you don't have a tax ID number, you probably won't be able to make wholesale purchases. 

Getting a Tax ID Online

If you're ready to acquire your tax ID, you can do so by visiting the IRS website or by getting in touch with a representative by calling 1-800-829-4933. When applying online, you should be aware that the online application is only available during certain periods of the day. Applying online is the easiest and fastest solution for obtaining a tax ID.

Essentially, the online application is a digital version of Form SS-4. This is the same form that you would fill out when applying for your ID number. Make sure that you fully review the form before you start working on your application. Knowing what questions you will be asked ahead of time will considerably speed up the process.

You can only use the online application if your LLC will operate principally in the United States or United States Territories. You will need either a Social Security Number, ITIN, or EIN to apply for a new tax ID number. Only a single person in your LLC is allowed to apply for a tax ID daily. You must also complete your online application in a single session. Online applications that are left idle for fifteen minutes will expire. Once your session expires, you will have to start your application over from the beginning.

The benefit of applying online is that you should immediately receive your tax ID number after your application has been submitted.

Other Ways to Apply for or Retrieve an EIN

While the IRS online application is the fastest option, you can also:

  • Apply by Fax or Mail: Submit Form SS-4 by fax to receive your EIN within about four business days, or by mail (processing can take up to four weeks).
  • Apply by Phone (International Applicants): Businesses with no legal residence in the U.S. can call 267-941-1099 (not toll-free) to apply.
  • Request an EIN Verification Letter (Form 147C): If you already have an EIN but need official proof, request a 147C letter from the IRS.

Tip: If your LLC changes ownership or structure, you may need a new EIN. Review IRS guidelines before making any changes.

Frequently Asked Questions

1. Is my LLC’s Tax ID the same as my state business ID? No. Your EIN is a federal identifier issued by the IRS, while state IDs are issued for state-level tax and registration purposes.

2. Can a single-member LLC use a Social Security Number instead of an EIN? Yes, if it has no employees, but using an EIN can help protect your personal SSN from exposure.

3. How long does it take to get an EIN online? In most cases, you’ll receive your EIN immediately after completing the IRS online application.

4. Do I need a new EIN if my LLC changes its name? Usually no. However, changes in ownership, structure, or converting to a corporation may require a new EIN.

5. What should I do if I lose my EIN? Check your IRS confirmation letter, past tax returns, or bank records. If you still can’t find it, call the IRS Business & Specialty Tax Line for assistance.

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