DEFINITION of 'Employer Identification Number - EIN'
A unique identification number that is assigned to a business entity so that they can easily be identified by the Internal Revenue Service. The Employer Identification Number is commonly used by employers for the purpose of reporting taxes.
BREAKING DOWN 'Employer Identification Number - EIN'
The EIN is a nine-digit number, and its role is similar to that of the Social Security number. The number includes information about which state the corporation is registered in. EINs can be applied for by phone, online or by mail. The digits of an EIN are formatted as follows: XX-XXXXXXX. Businesses that have changed their ownership structure usually must apply for a new EIN.