There are multiple ways to find your business tax ID, aka your employer identification number (EIN). The easiest is to dig up your EIN confirmation. The IRS provided this notice after you applied for your EIN. If you don’t have yours, there are other free options. These include simply 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.
Here are your EIN lookup options.
1. The easiest way: Check your EIN confirmation notice
You can apply for an EIN in multiple ways. Your choice will have determined how the IRS sent you this notice:
If you applied online. You would have received your EIN confirmation immediately online. You would have needed to print, save or download it at that moment.
If you applied by mail. The IRS would have mailed your notice. It could have taken up to four weeks for it to arrive.
If you applied via fax. The IRS would have faxed you back, provided you included a return fax number. This could have taken up to four business days.
Ideally, you will have stored your EIN confirmation letter alongside other important documents. These might include your business bank account information and incorporation papers. Chances are, you'll need to reference these documents several times a year.
2. If you can’t find the notice: Cross-reference other documents
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 through the following documents.
Federal tax returns.
Business licenses and permits.
Business bank account statements.
Business loan applications.
Payroll paperwork, such as 1099s you’ve received or issued.
3. Last resort: Call the IRS
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. EST.
The EIN application asks you to list a person responsible for the business. You'll need to prove you're that person to get your business tax ID over the phone. For instance, the IRS representative may ask for information like your Social Security number or date of birth.
🤓 Nerdy Tip
Be sure to locate your EIN before you file taxes, apply for a business loan or open a business bank account. Having your EIN on hand will speed up those processes. How to find another company's EIN
Occasionally, you might have to look up another company's EIN. This may happen when you're verifying a new supplier or a new client's information.
Here are some free ways to look up another business's EIN:
There are also commercial EIN databases you can pay to use. Doing so can make sense if you frequently need to look up EINs.
Businesses with state tax obligations may need a state employer identification number (SEIN) as well. This number is distinct from your business’s federal tax ID and is used on state tax forms. To find out whether you need a SEIN, visit your state’s tax department website.
Looking up your SEIN is similar to finding your EIN. You can check previous state tax return documents, and in some cases, business bank records. Some states also have online lookup tools.
There are several situations when you might need a new EIN, including:
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.
You can apply for a new EIN online via the IRS website. Once you get a new tax ID, you’ll use that number on tax returns and other business paperwork moving forward.
When not to get a new EIN
Most of the time, you probably don’t need to go through the trouble of applying for a new EIN.
Here are a few scenarios that don’t require a new business tax ID:
You change your business address.
You change your business name.
Your partnership or corporation declares bankruptcy.
Sometimes people get an EIN for a business and end up not needing it. In that case, you can write a letter to the IRS to deactivate the EIN.
However, the IRS can never fully cancel a business tax ID. Once you get one, it’s permanently associated with your business and cannot be reassigned to a different business.
Your deactivation letter should include the following information.
Your business’s EIN.
Legal name.
Reason for deactivating.
If you close your account and launch another business in the future, you'll need a new EIN.
Frequently Asked Questions
Do I need an EIN if I am self-employed? Do I need an EIN if I am self-employed?
The IRS uses EINs to identify individual business’s tax accounts. You’ll need to put it on all business documents you send to the IRS, including tax returns. Banks, lenders and other institutions may ask for your EIN for identification and tax-reporting reasons as well.
How do I get a tax ID number for a small business? How do I get a tax ID number for a small business?
You can apply for an EIN through the IRS, either online or by mail, fax or phone. This application process is free.
Is a business tax ID number the same as an EIN? 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.
Can you have a business without an EIN? Can you have a business without an EIN?
If you are self-employed and a sole proprietor or single-member LLC, then you don't legally need an EIN. However, there are a number of benefits of receiving an EIN that make it a good idea to apply for one. A version of this article originally appeared on Fundera, a subsidiary of NerdWallet.