As a business owner, you are assigned an Employer Identification Number (EIN) by the IRS. This unique identifier is also known as a Federal Employer Identification Number (FEIN) and has nine digits. Corporations, partnerships, non-profits, startups and other legal entities receive a tax ID at the moment of incorporation.

This number isn't just for tax purposes. Without it, business owners wouldn't be able to process payroll and conduct bank transactions. Any company that has employees, operates as a corporation or partnership and pays tax returns on employment, tobacco and alcohol must apply for a FEIN.

How to Conduct a FEIN Number Lookup

There are a number of ways to find the FEIN for your business or another organization. You can either call the IRS or check online databases. Another option is to search for this number on certain documents, such as old tax returns.

Beware that the IRS may not give you access to another company's FEIN unless you are authorized to request it. In this case, use the internet to conduct a tax ID lookup. Most databases require users to pay a monthly or annual fee, so research your options and choose a plan that suits your needs.

Call the IRS

The easiest way to do a FEIN check is to contact the IRS. Call the Business & Specialty Tax Line and request this information.

This option works as long as you are authorized to request a company's FEIN. Examples of an authorized representative include a company's owner, a corporate officer or a partner in a partnership.

Check Online Databases

Even though there are no official public records of tax ID numbers, several online databases provide this information. West Law, EIN Finder, FEIN Search and other services allow users to conduct a tax ID lookup in real time. Some provide a limited number of free searches.

Beware that this data isn't confirmed by official sources. It's available for information purposes only. The best way to look up a FEIN number is to contact the IRS. If you're researching a publicly traded company, check the SEC Fillings page. This online database is free to use and features more than 21 million filings.

Other Ways to Check FEIN Numbers

If you're searching for your own tax ID number, contact your business bank. They should have it on file. Another option is to check your last tax return or the original document confirming that you have been assigned a tax ID.

If you want to do a FEIN check for your employer, get this information from last year's W-2. If your employer filed for bankruptcy, this number will be listed on related court documents.

Not all companies are assigned a FEIN. For example, a small business or sole proprietorship that has no employees may not need this identifier, so you won't be able to find it.