This article has been reviewed by tax expert Erica Gellerman, CPA.
A business tax ID number, also called an employer identification number (EIN) or federal tax ID, is a unique nine-digit number that identifies your business with the IRS. Owners of most types of business entities need a business tax ID number to file taxes, open a business bank account, obtain a business license, or apply for a business loan.
Most people know their social security number by heart, but not all business owners know their business tax ID number. Your EIN isn't something that you use on a day-to-day basis, so keeping this number top of mind isn't as easy as remembering your company's phone number or address.
However, your EIN is essential for some very important business transactions, like filing business taxes and obtaining small business loans. Accuracy and speed matter in those situations. Not having your business tax ID can prevent you from getting crucial funding for your business or meeting a business tax deadline.
Ideally, you should memorize your business tax ID number or have it in an easily retrievable place. With everything competing for your attention as a small business owner, you might not realize that you don't know your EIN until you're midway through your tax return. Not to worry! Locating a forgotten, lost, or misplaced business tax ID is actually pretty easy and shouldn't cost you anything. Here is a guide to stress-free federal tax ID lookup. We also cover how to find another business's EIN.
How to find your business tax ID number:
Check your EIN confirmation letter
Check other places your EIN could be recorded
Call the IRS
Business tax ID number lookup: Your 3 best options
Many times, small business owners get stuck midway through a loan application, tax return, or bank account application because they don't know their business tax ID number. Fortunately, locating your EIN is pretty simple.
Here are the three best ways to look up your business tax ID number:
Option 1: Check your EIN confirmation letter
The easiest way to find your EIN is to dig up your EIN confirmation letter. This is the original document the IRS issued when you first applied for your EIN. The letter will show your business tax ID and other identifying information for your business.
If you applied online for your EIN, the IRS would have issued your confirmation letter right away, accessible online. You would have also had the opportunity to choose receipt by traditional mail.
If you applied by fax, you would have received your confirmation letter by return fax.
If you applied by mail, you would have received your confirmation letter by return mail.
Your EIN confirmation letter is an important tax and business document, so ideally you stored it away with other key paperwork, such as your business bank account information and incorporation documents.
In this sample EIN confirmation letter, you can find your EIN at the top of the page, as well as in the first paragraph. (Source: IRS)
Option 2: Check other places your EIN could be recorded
If you've misplaced your EIN confirmation letter, then you'll need to get a little more creative to find your business tax ID number. Fortunately, once you get an EIN, your tax ID typically won't change for the entire lifespan of your business. That makes locating the EIN easier.
These are some additional places where you can locate your EIN:
1. Old federal tax returns
2. Official tax notices from the IRS
3. Business licenses and permits and relevant applications
4. Business bank account statements or online account profile
5. Old business loan applications
Source: Small Business Administration
6. Your business credit report
7. Payroll paperwork (such as 1099 forms that you've received as an independent contractor or issued to independent contractors)
Note that your EIN generally will not appear on business formation paperwork, such as articles of incorporation, articles of organization, or a fictitious business name (DBA) document. These documents establish your business's legal setup but don't contain your business's tax ID number.
Option 3: Call the IRS to locate your EIN
You should be able to track down your EIN by accessing one or more of the documents listed above; but if you're still not having any luck, the IRS can help you with federal tax ID lookup. You can call the IRS’s Business and Specialty Tax Line, and a representative will provide your EIN to you right over the phone. The Business and Specialty Tax Line is open Monday through Friday from 7 a.m. to 7 p.m. ET. This should be your last resort, however, because call wait times can sometimes be very long.
Before you call, keep in mind that the IRS needs to prove you’re actually authorized to retrieve your business tax ID number. For example, you’ll need to prove you are a corporate officer, a sole proprietor, or a partner in a partnership. The IRS representative will ask you questions to confirm your identity.
Don't get frustrated: This is simply a precaution to help protect your business’s sensitive data. After all you wouldn't want the IRS to give out your social security number to anyone who called, would you? Once you've found your business tax ID number, we suggest putting the number in a safe place—like a locked file cabinet or secure cloud storage so you won't have to go through these steps again.
Why you need to know your business tax ID number
The IRS requires most types of businesses to apply for an EIN. The exceptions are some sole proprietors and owners of single-member LLCs, who can use their social security number instead of an EIN. But even small business owners who don't have to get an EIN often opt to get one, so that they're able to separate their business and personal finances.
If the IRS requires you to get an EIN or if you choose to get one, these are some of the situations where you'll need to provide your business tax ID number:
When filing business tax returns or making business tax payments
When applying for a business loan
When opening a business bank account
When applying for a business credit card
When issuing Form 1099s to independent contractors
Although each of these transactions doesn't happen regularly, when you consider all of them together, you'll need to provide your EIN at least a few times per year. So, this is a number worth committing to memory and storing safely. Ideally, you should retrieve your business tax ID before you complete any of the transactions above.
How to find another company's EIN
Usually, small business owners need to locate their own company's tax ID number, but businesses sometimes need to look up another company's EIN. For example, you can use an EIN to verify a new supplier or client's information. Also, in industries like insurance, you might need other companies' EINs during your daily course of business.
Use one of the following options to find another business's federal tax ID number:
1. Ask the company
Someone in the payroll or accounting department should know the company's tax ID.
2. Search SEC filings
If the company is publicly traded, look at the Securities and Exchange Commission's website and enter the company's name. The SEC filings should contain the business tax ID number (listed as "IRS No.").
3. Inquire with a credit bureau
Credit bureaus allow you to purchase your own business credit report or view another company's business credit report for a fee, but these reports won't always show the company's EIN. Confirm that the report you're considering will contain the EIN before you order it.
4. Use a paid EIN database
Another option is to search a commercial EIN database, which will charge a fee for access to company EINs. Some databases even link EINs to other information, such as company size and industry. This can help you find new prospects.
5. Use Melissa Database for nonprofits
The Melissa Database provides free federal tax ID lookup for nonprofit organizations.
If you have a legitimate need to find the EIN for another business, then you can use one of these options to look up the number. Just be sure to keep your own EIN secure. Only share the number with a limited subset of people—lenders, prospective suppliers, bankers, etc. You should guard your business's EIN just like you would guard your social security number.
How to change or cancel an EIN
Once you obtain an EIN for your business, that tax ID remains with your business for its entire lifespan. However, there are some situations where you might need a new business tax ID number.
Here's when you'll need to apply for a new EIN:
You incorporate for the first time or change your business entity
You buy an existing business or inherit a business
Your business becomes a subsidiary of another company
You are a sole proprietor and are subject to a bankruptcy proceeding
You are a sole proprietor and establish a retirement, profit sharing, or pension plan
You receive a new charter from your state's Secretary of State
There are changes to your ownership structure
The IRS has a detailed list of situations where you need a new EIN. A new EIN replaces your old EIN, so once you get the new tax ID, you would use that on tax returns and other business paperwork moving forward. Once your business gets an EIN, the IRS technically can't "cancel" the tax ID. Even if you close down your business and never file a tax return, no other business will ever get the same number. If you ever decide to reopen your business, you can use the old number. If you determine that you don't need an EIN that you applied for—maybe because you never actually started the business or because you dissolved the business—then you close your business account with the IRS by writing a letter. If you close your account and launch another business in the future, you'll need a new EIN at that point.
Frequently asked questions
1. How do I get a tax ID number for a small business?
Getting a tax ID number is simple. Once you've determined your eligibility, you can apply for an EIN through the IRS, either online or by mail, fax, or phone. This application process is free. You can also use an online legal service to apply for an EIN, but they will charge a fee for this service.
2. Is a business tax ID number the same as an EIN?
Yes, a business tax ID number is also known as an employer identification number, or EIN.
3. Can you have a business without an EIN?
Yes, depending on the type of business. Single-person LLCs and sole proprietors don't need an EIN because they're taxed as individuals. However, if you plan on opening a business bank account as another entity besides those that are taxed as individuals, an EIN is required more times than not.
4. Do I need an EIN if I am self-employed?
If you are self-employed and are an official sole proprietor, then you don't legally need an EIN. However, there are a number of benefits of receiving an EIN, including to help separate your personal and business finances.
The bottom line
Knowing your business tax ID number is important, but with all of the competing attention for a small business owner, you might forget or misplace your tax ID.
Here's what you should know if you need to locate an EIN:
Locate your EIN before you need to file taxes, apply for a business loan, or open a business bank account because it will speed up the process.
You can locate your EIN on your confirmation letter from the IRS, old tax returns, old business loan applications, your business credit report, or payroll paperwork.
You can also call the IRS to look up your federal tax ID number.
If you need to locate another company's EIN, you can start by asking the company. There are also free and paid databases that can help you find a business's tax ID number.
Once you apply for your company's EIN, you won't need a new one for business name changes or location changes. However, if your business's ownership or structure changes, then you'll likely need a new EIN from the IRS.
Your business tax ID number is important for many business milestones. Make sure you keep this number safe so you'll have it whenever necessary.
A previous version of this article misstated whether all business credit reports will show a company's EIN. It has been corrected here.