EIN Lookup: Free Ways to Find Your Business Tax ID Number

The easiest way to find your business tax ID — also known as an employer identification number (EIN) — is to dig up your EIN confirmation. This is the document the IRS sent you when you applied for your unique employer identification number. There are additional free options if you’ve misplaced that notice, including calling the IRS.

One thing the IRS doesn’t offer: a public EIN lookup tool online. That means you’ll need to go an alternate route if you’re searching for a different company’s tax ID and not your own.

Here’s what to know about looking up an EIN — for your business and others.

» MORE: 21 small-business tax deductions to know

How to find your EIN

Here are your EIN lookup options.

1. Check your EIN confirmation notice

If you applied for your EIN online, you should have had an opportunity to download, save and print your EIN confirmation notice. Business owners who got an EIN via mail or fax should have received this confirmation via their respective application method. Start by tracking down that document.

Your EIN confirmation letter is an important tax and business record, so it’s best to store it alongside your business bank account information and incorporation documents. Many business owners need to use this number several times a year.

2. Check other places your EIN could be recorded

Most businesses never change their EINs. If you’ve used your EIN in the past, there’s likely still a record of it somewhere in your files.

Try looking up your EIN on the following documents, most of which require your business tax ID number:

• Federal tax returns.

• Business licenses and permits. 

• Business bank account statements.

• Business loan applications. 

• Payroll paperwork, such as 1099s you’ve received or issued. 

» MORE: Can you open a business bank account without an EIN?

3. Call the IRS to locate your EIN

If you can’t find your EIN in your files, call the IRS’s Business and Specialty Tax Line at 800-829-4933. The line is open Monday through Friday from 7 a.m. to 7 p.m. local time.

You’ll need to prove you are a corporate officer, a sole proprietor or a partner in a partnership in order to receive your business tax ID over the phone. The IRS representative who answers will ask you questions to confirm your identity.

How to find another company's EIN

You may occasionally need to look up another company’s EIN — for instance, if you’re verifying a new supplier or client’s information.

You have the following free options when looking for another business's federal tax ID number:

• Simply ask the company to provide it.

• If the company is publicly traded, search SEC filings using its EDGAR tool.

• If you’re looking for the EIN of a tax-exempt organization, like a charity, you can look them up online with the IRS.

There are also commercial EIN databases you can pay to use. Doing so may make sense if you frequently need to look up EINs.

» MORE: A guide to income and payroll taxes for LLCs

How to change or cancel an EIN

If you’ve misplaced your EIN, don’t apply for a new one — look it up instead. Once you obtain an EIN for your business, that tax ID remains with your business for its entire lifespan.

However, there are a few situations where you might need a new business tax ID number. These include:

• 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.

Once you get a new tax ID, you’ll use that number on tax returns and other business paperwork moving forward.

If you determine that you don't need an EIN that you applied for — maybe because you never actually started the business — then you can cancel it by writing a letter to the IRS. If you close your account and launch another business in the future, you'll need a new EIN.