An employer identification number (EIN) is a unique nine-digit number assigned to businesses by the Internal Revenue Service for tax-reporting purposes. Nearly every kind of business needs an EIN, including corporations, limited liability companies and partnerships. EINs are used by businesses to send invoices, statements and tax documents. If you have the EIN of a business but don't know who the number belongs to, there are several resources you can turn to to find the owner.

Go to the Corporations Systems Search Results page of the Pennsylvania Department of State website (see Resources for a link). Type the EIN into the "Entity Number" search box. If the EIN is attached to a corporation or LLC, the business name appears in the search results.

Go to the Guidestar Charity Check website (see Resources for a link) and type the EIN into the EIN search box. If the business is a nonprofit, the business name appears in the results list.

Navigate to (see Resources for a link) and type the EIN into the "Tax ID" search box. Although search results are free, you must pay a fee to see full details.


Visit your local Pennsylvania public library and ask the reference librarian if the library subscribes to a database like Reference USA. You may be able to perform a search on that database for free if your library subscribes to it.