Where to find a company's tax ID in three places

A company's tax ID number — formally called an Employer Identification Number (EIN) — is public information you can look up for free. The fastest route is the IRS website itself, which has a tool that searches by company name. If that does not work, the company's own documents (invoices, contracts, or their website) usually list it. A third option is your state's business registration database, which keeps records of all registered companies in that state.

You do not need permission from the company to look up this number. It is filed with the federal government and is meant to be found. The process takes minutes once you know where to look.

Key Takeaways

  • The IRS Tax Exempt Organization Search tool lets you search by company name and returns the EIN if the company is registered.
  • Many companies print their EIN on invoices, contracts, and their official website under "About Us" or legal information.
  • Your state's Secretary of State office maintains a business database where you can search by company name to find registration details including the EIN.
  • If a company has no EIN, it may be a sole proprietorship or partnership that uses the owner's Social Security number instead.

Using the IRS Tax Exempt Organization Search

The IRS maintains a searchable database of tax-exempt organizations at tax-exempt-organization.irs.gov. Go to that site, enter the company name in the search field, and click Search. The results will show the organization name, city, state, and EIN if it is registered as a tax-exempt entity.

This tool works best for nonprofits, charities, and educational institutions. If you are looking for a for-profit company, this database will not have it — you will need to use one of the other methods below. The search is free and does not require you to create an account.

Checking the company's own documents and website

Many companies list their EIN on their official website, usually in the footer or under a section titled "About Us," "Legal Information," or "Contact Us." Look for a line that says "EIN:" followed by nine digits in the format XX-XXXXXXX.

If the company has sent you any official paperwork — an invoice, contract, W-9 form, or year-end statement — the EIN is often printed there as well. Invoices and contracts are especially reliable because companies are required to include this information on official business documents. If you have received mail from the company, check the letterhead or any enclosed forms.

Searching your state's business database

Every state maintains a registry of businesses registered to do business within that state. These databases are run by the Secretary of State office (or a similar agency) and are open to the public. Go to your state's Secretary of State website, find the business search tool, and enter the company name. The results will show the company's registration details, which usually include the EIN.

The exact name of the tool varies by state — it might be called "Business Entity Search," "Corporate Records Search," or "UCC Search." A quick search for "[your state] Secretary of State business search" will take you to the right page. Most states do not charge a fee to search.

What to do if the company has no EIN

Not every business has an EIN. Sole proprietorships (one person running a business) and some partnerships do not need to register for an EIN with the IRS. Instead, they use the owner's Social Security number as their tax ID. If you cannot find an EIN for a small business, this is likely why.

If you need a tax ID for that business and cannot find an EIN, contact the business directly and ask for their tax ID number. They will tell you whether they have an EIN or use a Social Security number. If they use a Social Security number, you may be able to request it depending on your relationship to the business — for example, if you are a contractor, they are legally required to provide it on a W-9 form.

Understanding the EIN format and what it means

An EIN is always nine digits long and is written as XX-XXXXXXX (two digits, a hyphen, then seven digits). The first two digits indicate the state where the business was formed or the IRS office that issued it. The remaining seven digits are unique to that business.

The EIN is not secret — it is public record. Any business that has employees, operates as a corporation or partnership, or has certain types of income is required to have one. If you see an EIN listed on a company document, that is the correct number to use for tax purposes, vendor verification, or background research.

Why you might need a company's tax ID number

You may need to look up a company's EIN for several reasons. If you are a contractor or vendor, the company will ask for your EIN on a W-9 form — and you may need theirs for your own records. If you are researching a nonprofit's finances, the IRS database will show their EIN along with links to their public tax filings. If you are verifying that a business is legitimate, the EIN confirms it is registered with the federal government.

Some people also look up an EIN to check whether a company is actually registered or to confirm the correct legal name of a business before signing a contract. The EIN is one of the fastest ways to verify that a company exists and is in good standing.

Frequently Asked Questions

Can I look up a company's EIN without their permission?

Yes. An EIN is public information filed with the federal government. You do not need permission from the company to search for it. The IRS and state databases are open to anyone.

What if I search and find multiple companies with the same name?

This happens often, especially with common names. Look for the city or state to narrow it down. If you still cannot tell which one is correct, contact the company directly and ask them to confirm their EIN. They are required to provide it.

Is an EIN the same as a Social Security number?

No. An EIN is issued by the IRS to businesses, nonprofits, and other entities. A Social Security number is issued to individuals. Some small businesses use the owner's Social Security number as their tax ID instead of an EIN, but the two are not the same thing.

How long does it take to get an EIN if a company does not have one?

A business can explore for an EIN online through the IRS website and receive one when ready. If they explore by mail or phone, it can take several weeks. Most businesses explore online and have their EIN within minutes.

Can I use a company's EIN to look up their tax returns?

For nonprofits, yes — their tax returns (Form 990) are public record and searchable by EIN on the IRS website. For for-profit companies, their tax returns are private. You can only see what the company chooses to make public.